Well I just tried 1/4 stepping on the z and it sounds much better (smoother) with no resonance. I just ran part of my test g-code and apart from one motor stall at the beginning it seemed to run with no lost steps.

I am going to change the y to 1/4 stepping to as that motor tends to resonate. As per someone else mentioned (I think George), my x is fine so I will leave that at 1/8.

back to testing.

I would make all three the same, and maybe try 1/2 step

David did you try or can you try the two computer PSu's wired together to give you 24v. min. and over 10 amps?

CCSparky, what is the amps of your PSU ?

I Still believe 5 amps in not enough to make it work properly.

One other thing, can you take the shuttle out of the equation and use keyboard arrows? and change jog rate, or press the tab key in mach to use the jog feature with the mouse.

Joe,

10 Amps, here's a link to the data sheet
http://www.alliedelec.com/Images/Products/Datasheets/BM/TRIAD_MAGNETIC/F-401U.pdf

I just put a video on my website (web.mac.com/dacostad (http://web.mac.com/dacostad)), titled z-axis problems so you can see and hear what is going on.

david, that video keeps crashing firefox and internet explorer :(

david, that video keeps crashing firefox and internet explorer :(

No problem with the video on my end. Maybe the codec for the video needs to be updated on your PC?

maybe, let me try my desktop

Works alright here too :)

Regards,
Bob

The video worked, but the motor growl sure grated.

Sorry, did not spend the time to put on a relaxing soundtrack ;)

works now upgraded quicktime codecs.. router looks good, I would like to order the electronics by tomorrow, so you think the xylotex kit is still going to be okay and it might be the computer or the power supply?

I need to try giving it more power and I should have 2 cheap computer power supplies on Tuesday to try them in series at 24v 10a. I also ordered the 425 oz/in motors as I figured that having the extra low end torque would do no harm. So I am afraid the jury is still out until next week, but I know George seems to be working okay with the Xylotex / 425 oz motors on his router.

so what's the verdict on my part, hold off for now or order the ready kit from xylotex? or should I go the hobby cnc route?

Well we know that Joe has the HobbyCNC kit with the larger power supply and it works, however it depends on how confident you are with electronics.

If you can wait, I will have both the larger stepper and psu early next week and will start testing as soon as I receive it.

I got my 425oz/in steppers delivered today (very fast) so I have grafted the 425 on in place of the 269 on the z axis and ran my test again (raising 1" and lowering 12 times) and I am happy to report that it lost no steps at all.

I also noticed that when I jog the axis up with my shuttle express very slowly whereas before it would just stall now it moves up very slowly. I guess that is the benefit of the extra low end torque. I know I sacrifice high end speed but I am not sure what the high is on these motors but I suspect it is higher than I will run at. The movement is a lot smoother sounding.

So question for the experts; The end point with me playing with the controller is I have the psu volts set at 28.5 and the vref on all three axis set at 3.6 (the max for the board) and microstepping set at 1/4, do you think it is worth dialing the vb back to 27.5 and the vref down to say 3.3 and changing the stepping back to 1/8?

Now to put the bigger motor on the y axis and see how that sounds.

Sounds good Joe. Hope everything turns out nicely. How are your bearing slides? I was talking with joe about them, I'm not all that perfect with mine but my tolerance was to try to be a 32nd. Somehow 1 or two of the bearings on each z carriage slide aren't touching but it's strong as hell. Thinking of shimming them but will play with it first all together before I tweak things like that. Pics coming tonight of progress ;). I'm probably going to just order the pc and components and order the xylotex/motors/drivers later on after I watch how yours turns out. I'm in no rush, I've got my hands full haha.

My bearings are pretty much the same as yours. I made mine on my cnc sherline mill so they should all be pretty much the same. Not sure its worth disassembly to shim them unless something is way out. I think as long as none are so tight as to induce friction on the axis and as long as you cannot wobble the axis I think it is fine.

Just put the motor on the y and about to test again.

I got my 425oz/in steppers delivered today (very fast) so I have grafted the 425 on in place of the 269 on the z axis and ran my test again (raising 1" and lowering 12 times) and I am happy to report that it lost no steps at all.

I also noticed that when I jog the axis up with my shuttle express very slowly whereas before it would just stall now it moves up very slowly. I guess that is the benefit of the extra low end torque. I know I sacrifice high end speed but I am not sure what the high is on these motors but I suspect it is higher than I will run at. The movement is a lot smoother sounding.

So question for the experts; The end point with me playing with the controller is I have the psu volts set at 28.5 and the vref on all three axis set at 3.6 (the max for the board) and microstepping set at 1/4, do you think it is worth dialing the vb back to 27.5 and the vref down to say 3.3 and changing the stepping back to 1/8?

Now to put the bigger motor on the y axis and see how that sounds.

you can go back to the 1/8 micro, but set the vref to the recomended settings.

Also i would install better power supply.

Thanks Joe. I'll set the stepping back to 1/8 and the vref to 3.42.

Agree with the power supply as I still am not convinced I have totally solved my problems. I should have the pc psu on Tuesday

So at the end of today I have the 425 motors on the y and the z (I'll do x tomorrow). I have set VBB and VREF to the same as George (27v and 3.36) with 1/8 microstepping, I have x and y set to 70 vel and 8 acel and z to 4 and 2 all with 4 pulse width for step and direction. If I run a simple v-carve of my name at 20ipm I loose steps.

So next is the psu which is scheduled for Tuesday.

Could there be any other Mach 3 settings which are causing me problems?

Could there be noise induced by my all in one PC/Controller approach?

Could my 1.6Ghz P4 micro flex based computer be causing problems?

Tomorrow I will compare my settings in Mach 3 with those I have on my other pc I use with my Sherline CNC in case I have set something wrong by accident.

So at the end of today I have the 425 motors on the y and the z (I'll do x tomorrow). I have set VBB and VREF to the same as George (27v and 3.36) with 1/8 microstepping, I have x and y set to 70 vel and 8 acel and z to 4 and 2 all with 4 pulse width for step and direction. If I run a simple v-carve of my name at 20ipm I loose steps.

So next is the psu which is scheduled for Tuesday.

Could there be any other Mach 3 settings which are causing me problems?

Could there be noise induced by my all in one PC/Controller approach?

Could my 1.6Ghz P4 micro flex based computer be causing problems?

Tomorrow I will compare my settings in Mach 3 with those I have on my other pc I use with my Sherline CNC in case I have set something wrong by accident.

You must have a grounding problem or something. With those motors you should be able to move a mountian at 20 IPM....

I suspect you must be getting noise or something....

Garry

ANd there have some problems in the past with some of the non standard computers. However if the driver test test runs well you should be good, if you port output is high enough and stable. The part that make no sense is that it works worse the slower you go.. This has never been my experence with steppers.

Garry

Make sure the pulse width is set to 2 or 3 in the motor tuning screen. And you could check if your getting 5V from the parallel port, and not 3.3V.

That's what I don't understand either. The v-carve test was run with 10ipm plunge and 20 ipm feed, that's why I wonder if I have got something set wrong in Mach 3, but I can't think of anything that would cause me to incrementally cut deeper.

Maybe it noise or grounding and if I can't resolve this after Tue when I try more power (amps) then I may just rip all the driver related electronics out of the pc and mount them in a separate case.

Thanks Gerry I will change the pulse width tomorrow to 2 or 3 tomorrow as it is now at 4 and check the the parralel port for 5v. I assume all I need to do there is with the PC on put a voltmeter on the appropriate pin?

I am going to be checking and testing a number of things today, but just wanted to confirm that at 1/8 stepping I have the motor tuning setting set to 16000 steps per unit in Mach 3. I am pretty sure this has to be correct as I am seeing a 1" movement in the axis for 1" movement on the dro. Can someone confirm please.

I am going to be checking and testing a number of things today, but just wanted to confirm that at 1/8 stepping I have the motor tuning setting set to 16000 steps per unit in Mach 3. I am pretty sure this has to be correct as I am seeing a 1" movement in the axis for 1" movement on the dro. Can someone confirm please.

yes that is correct, 10tpi x 200 steps x 1/8 micro - 16,000

Thanks Joe.

I tested the computers parallel port using pins 3 and 18 my voltmeter and I saw
.049 with the scale on the voltmeter set to 2. This climbed up to .074 when joging any axis in any direction.

I would have expected 4.9 and 7.4 but I don't really know what I am doing with electronics or the volmeter.

Can someone confirm that what I saw is okay.

Thanks

You can't really measure the step pin with a voltmeter, because the steps are too fast. Try measuring the direction pin, or set up an output and turn it on and off. The direction pin should give you 5V in 1 direction, and 0V in the other.

Thanks Joe.

I tested the computers parallel port using pins 3 and 18 my voltmeter and I saw
.049 with the scale on the voltmeter set to 2. This climbed up to .074 when joging any axis in any direction.

I would have expected 4.9 and 7.4 but I don't really know what I am doing with electronics or the volmeter.

Can someone confirm that what I saw is okay.

Thanks

can you take picture of meter and circle the setting you had it on?

also check the breakout board and see if you get the same effect.

Gerry, port three is the direction pin for the x axis which now confuses me more as I don't understand why I would see movement on the voltmeter for all axis. I will try as you suggest and setup an output for a separate pin.

Joe here is a picture with the setting circled.

Thanks guys - your help is much appreciated!

Okay, confusing myself, Gerry you were right I had it connected to the step pin. Connected to a direction pin I see 5.11v in one direction and 0.05v in other direction (with vm on 2). Sorry about that.

So I guess that is alright, I will check to see if I get the same coming out of the breakout card before its connection to the xylotex.

Okay coming out of the CNC4PC multifunction card from the db25 connector that normally goes to the xylotex I see 5.21v in one direction and -0.00 in the other.

I ran the driver test for mach 3 and although I do not see any spikes I do see low level "noise" that comes and goes on what appears to be a regular cycle.

Is this okay or could it cause any of my issues?

Attached is a movie of 30sec extract (zipped)

David,

Those little spikes are OK as they are the various background Windows processes. One thing that I did was to "tune" my WinXP to run Mach3. I created a little "batch program" to stop all unnecessary Windows services. There is a "tuning" document available at the Mach3 web site that will explain how to eliminate various Windows processes that may interfere with the Mach3 process.
Another problem that I had was "crosstalk" on my limit switch wires with the stepper cables. I separated the limit switch wires from the stepper cables and the problem went away. Make sure that you have good ground connections on the stepper cables. Your "ground plane" may be noisy and could cause intermittent problems. Recheck your solder connections. “Cold” solder connections can cause all kinds of weird problems,

Dave

Thanks Dave, I have already gone through the optimization file and implemented everything except for setting Computer to Standard PC NOT ACPI as the pc will not boot if I do.

Thanks for the tip on the cross talk. To eliminate this as a problem can I just disconnect the limit switches?

David,

Just disable the limit switches in Mach3. You don't have to disconnect them physically, although you can do this. BTW, my JGRO is running with 118oz in. steppers and I can push them to 50ipm without problems, although I only cut at 30ipm and rapid at 50ipm You should be able to easily run this speed on your Joe’s machine with your larger steppers.

Dave

Thanks Dave.

Interesting about your JRGO with the 118oz/in as I have Sherline CNC setup on my mill and lathe which are 135oz/in running with Sherlines controller and on a seperate PC with Mach 3. I have thought about putting the Sherline setup (motors/ controller and pc) and see what happens as a test.

I figure that if it all runs fine albeit at slower speeds/accel then it would confirm that I have a pc/controller/wiring problem. If I still have problems it would tell me that I have a mechanical problem.

What do you all think about that as a strategy?

David,

Swapping the motors and controller will tell you if your existing setup is the culprit. The 135oz in motors should be able to push your machine, although slower than your existing setup, but it will tell you where the problem is. Remember, steppers have greater torque at slower speeds, so running the smaller steppers will work, only slower. You will loss steps with smaller steppers at faster speeds as the torque decreases.

Dave

David,

Getting any closer to solving your problem?

I brought the Xylotex kit and one stepper home tonight so I could get some hands on with it in hopes of getting it set up this week. I'll keep you posted if I find a problem with mine.

One thing I did notice today and you may have covered this already is, when I installed the acme rod into the z-axis carriage I notice a slight binding when it fed through the lower bearing. I started from the top and fed it down, all was fine until I reached that bearing. The acme rod on the z-axis was the last of the three I installed. I had used a wrench and drill motor to install the previous two and did the z-axis by hand. When I got to the lower bearing it became very difficult to turn and I probably would not have noticed it if I had been using a wrench. Just a thought.

Yes I noticed a little binding two but once in place I could still turn the leadscrew with the router mounted with my fingers. I also enlarged the holes on the bottom a little to allow the bearing mount to move out slightly and take the pressure off a little

I am really begining to suspect that my problem is noise related and could be due to me building the controller into the pc.

Tomorrow I will run without the limit switches to see if the noise is coming from them, but I dont think it it. I will also put my sherline motors/ controller and pc on the router and see if that cures the problem, which I think it may.

I have ordered the same HP desktop that bp092 has ($390 for a 3Ghz P4 is a bargain.) and if my suspicions prove to be true I already have the case to rebuild the controller stand alone.

One thing I did notice today and you may have covered this already is, when I installed the acme rod into the z-axis carriage I notice a slight binding when it fed through the lower bearing. I started from the top and fed it down, all was fine until I reached that bearing.


I was just looking at the drawings again to see why this might be happening. I am not sure how you did it but if you are going through the top, bottom bearings and also throught the AB nut. Then you have 3 points that have to be aligned. One ting to consider is that if your truck bearings are off by a few thousand from Joe's then you could have your AB nut missaligned. You also have to rmember that you are installing 8mm bore onto a 5/16 shaft not exactly a tight fit. If you are feeding down from tha top and through the Ab nut, then once you get to the lower bearing if you have to move the shaft back then you need to move the Ab nut back. You could just shim it. If you have to move it forward then you will be better off trimming the AB nut mounting assembly. I found when building the router I have that it takes very little missalignment to cause one of theses motors to bind up. Hope this is some thoughts that will help.

Dwayne

http://www.newegg.com/Product/Product.asp?Item=N82E16883107184 for the pc david was referring to, what a steal (if anyone wants it) just get a monitor and mach 3 and you're set, hell that thing is fast enough to run some decent software for drawing up parts and what have you..

David and Joe.....

Minor update as I am about to start a 4 day business trip.

My table is now off the saw horses.....!!!!

I have mounted my table permanently. A few adjustments still need to be made. My cable chains are in and all "real" cables are run including limits/home. I have not yet mounted the limit switches so the limit cables are just hanging unconnected. I have however connected all stepper motors to the Xylotex drive using the permanent cables. The Y & Z cables are in the cable chains and all buttoned up.

Just as a reminder - I am using a stock Xylotex board (this one happens to be a 4 axis model but I am only using 3 -XYZ). I am using the stock Xylotex 24V/5A power supply and 425 oz/inch motors also from Xylotex.

My max velocity settings are 80 IPM for X, 80 for Y and 100 for Z. I use the drive in 1/8 step mode. With a few adjustments, I am confident I can get X & Y to go faster but may not bother.

In between major distractions from my real job's work.....I have continued to test air cut. I ran through an extensive VcarvePro sample file (the Wendy's sign - my daughter wanted to watch that one). I mounted my laser edge finder in the router collet and carefully marked X0, Y0 on a piece of tape stuck to the table. I used some tape and alignment witness marks for the Z. After multiple toolpaths from the sign, my laser point returned to the mark - dead on AND the Z witness marks were in line.

Suggests that I did not loose any steps.

I have run several air cuts as above with the router spindle turning but NOT cutting anything but air - same results.

So, the only things NOT tested are:

1. Will the resistance provided by moving the router bit through the wood influence the step integrity?

2. Will hooking up the limit wiring cause electrical noise that impacts step integrity?

Based on what I have seen so far, I do not think by setup will induce electrical noise. Time will tell.

When I return from my trip I will finish up the limit connections and begin cutting. I expect to provide pictures as well of my lift mechanism and a few other special adds.

By for now.

Regards,
George

Thanks for the update George.

Do you have your Xylotex seperate from the PC?

I am beginning to think that my "all in one approach" is causing noise issues, so today as mentioned I am going to hook up my complete Sherline CNC setup to see if I can run with no lost steps.

I am beginning to think that noise is my issue.

Quick update, I just put my sherline Z axis motor on and ran it from the sherline controller (24v 4a) and different pc jogged it up and down and it sounds totally different, very smooth in both directions, now to put the other axis on.

Quick update, I just put my sherline Z axis motor on and ran it from the sherline controller (24v 4a) and different pc jogged it up and down and it sounds totally different, very smooth in both directions, now to put the other axis on.

Sounds promising...
The all in one sure looks nice, maybe it could be double shielded if it really ends up being the problem....

Garry

Well all axis are on and it sounds perfect! The y and z which allways sounded bad now sound totally smooth in all direction.

I am now going to try to cut something!

Well guys I am extremely happy to report that I can confirm my problems are almost certainly noise.

I have connected my Sherline 135 oz/in steppers up along with the Sherline controller and separate PC.

The machine sounds totally different with all three axis smooth in all directions.

I just cut a v-carve David and it cut perfectly. I ran the motors at 40 vel and 2 accel.

My next step is to put the 425 back on and hook it up to the Xylotex controller in the PC and see if I can find the noise source. Ultimately I think I may end up putting the controller in a separate case although that does not guarantee no noise. I wonder about the ac power I have going to the CNC4PC multifunction card for the Router on/off and the other power sources floating around inside for the multifunction card and controller.

If any body has tips on ways to suppress noise I would be grateful.

Thanks

David

Thank heaven for that :)

I have been watching for while and it is good to see the progress :) and it is going positive now :)

Good one.

Cheers,
Bob

David,

Glad to hear that you have seen improvement!

(I am on the road so no ability to look at anything on my setup)

All of my stuff is seperate.

PC - off the shelf Dell GX-60 that has been sitting around doing nothing for a while (was my son's computer before we upgraded his to a serious gamer machine).

CandCNC mini-io box (connects via 2 parallel cables to PC, also has MPG - see their site for reference). This unit is powered via AC mains - seperate 2 wire AC plug. This is essentially an enhanced breakout board with step and direction status lights.

Xylotex chassis - driver board and power supply inserted into old AT PC power supply box (old power supply board removed, only AC IEC plug and AC power switch remained installed) I installed the Xylotex driver board stacked on top of the Xylotex 24V power supply via standoffs. The 24V supply is also mounted on standoffs to the bottom of the gutted power supply box. I acquired a 92mm 24VDC fan (powered by the Xylotex supply) from Jameco as a direct replacement for the 12VDC fan origninally installed in the PC power supply box (more air and much quieter than the Xylotex mini-fan). The Xylotex driver is connected via DB25 cable to the mini-io box.

The mini-io kit I purchased came with a "remote-relay and limits board." It is about 2" x 2" and has two power relays and spade lug inputs for 4 homes/limits & Estop switches. It connects via a DB9 cable back to the mini-io. I installed it into a small plastic - see through covered case so I could observe the limit/home/relay status LED's. It is mounted to the end of the table. It is powered by a 12VDC wall wart power supply. It supplies the AC switch for my router.

As a 30+ year electrical & computer systems engineer, I new instinctively to worry about electrical noise. I chose my setup with "malice and aforethought" just to avoid electrical noise gremlins. While I love nice tight all-in-one chassis setups, I went for modularity instead. So I have to stuff everything inside cabinets vs. your approach.

George

Thanks for the info George.

Electronics is not my strong suite once you go any deeper than building PC's which I have done a lot off.

One good thing about all my problems is that it has been a great learning experience and I certainly know more now than I did at the outset.

It is so nice to be able to finally know for sure that the machine it self runs perfectly and I did not screw up the build.

Thanks for all the help George, Gerry, Joe and everyone else who either provided suggestions or just encouragement.

Glad it works for you, post the V-Carve you did, just to show progress... :)

Just think of all the other people you have helped by figuring out problems.

I would go ahead and seperate everything, then use a larger PSU when you can, this is always a good thing.

Joe

I would post the v-carve but the piece of MDF its cut into looks like a battle ground with lots of holes, gouges etc from previous tries to cut ;)

The 2 computer PSU turned up this afternoon so I am just modifying them now to run in series and will test current setup just to rule out amps as the sherline controler was 24v 4a.

That's great news!!!

I'm still tinkering with my Xylotec kit, sorry I didn't get done in time to help and thanks if I run across the same issue, I know where to look now that you guys have already worked out the kinks :D

Like Joe said, pictures please! :)

Joe, I have my two PC PSU wired in series now giving out 24v. Each 300w PSU states that at +12v it gives 13amps.

In series I assume I now have 24v 13amps (not 26 amps). As each axis on the Xylotex has a max amp of 2.5 do I need to adjust anything before I hook the PSU's up? I assume the board will just draw the amps it requires the point being that at max with all 3 axis moving their will be plent amps (13) available.

Sorry for the really dumb electronics questions.

David

David,

The driver controls the current individually to each stepper with a max of near 2.5 amps per motor.

The style of power supplies you have connected do not have current control though they may have current limits (a fuse for instance). Think of them as a sophisticated battery.

Switching power supplies (PC style) often do not register the standard output voltage until they are under load. I would check anyway WITHOUT ANY LOAD to determine if it is at or near 24 V with a volt meter. I would then hook up a 24V fan, just to check. Then you can apply power to the board. The 12 V power lead from the high supply will be +24 V and the ground lead from the low supply will ground for the driver. I assume you followed the instructions that require the high supply NOT be earth referenced.

George

Thanks George, Yes I did and I hooked the leads up to a voltmeter and indeed I am getting 24 volts.

To those viewing David's thread...

Just to pontificate......on power supplies.

Mathematically, the 24V 5 Amp supply from Xylotex should be plenty when applied to as many as 4 axes where the motors (as supplied by Xylotex with the ratings published) are no more than the 425 oz/inch motors. The ratings on the 497's they have would get real close to the edge......

The duty cycle (when the step pulses are actually happening) is NOT 100%. Even though the step pulses may be really close together, there is measurable time between the pulses (not talking about time between moves here, I am talking about the space between actual pulses DURING THE MOVES). So, the drivers spend a significant amount of time in between pulses NOT delivering the maximum current (2.5 Amps in this case). This is a classic case of a square wave - some portion of time on and some portion of time off. That by the way is what a "chopper" drive does. The higher "power" demand is delivered when it is ON during the actual pulse. Power = Volts x Amps = Watts. (For the engineers in the audience, it is actually more complicated than that as there is significant inductance and capacitance in these circuits which alters that formula.) When you are delivering current pulses at the frequencies we are working with for CNC (thousands of cycles per second or Hertz), the effect is that the NET power demand is NOT the full current rating! That is how you can get away with a PS with a 5 AMP rating when the apparent need might be 7.5 AMPS

In the case of steppers, there is always some current required as they need power to "lock up." The holding current is almost always dramatically smaller than the current to overcome inertia and spin. Steppers and Acme screws, more often than not, have no issue as Acme screws in the 10 TPI range and up will generally NOT rotate in a "backdrive" mode. Steppers and ball screws (or very low TPI Acme) could be another story......ball screws most definitely rotate when force is applied to the nut (like the weight of a mill head on a column). Can you CNC mill owners with ball screws say "keep your gibs tight?"

So....

If all three motors were at max current at the same time CONTINUOUSLY [not pulses] for more than a few seconds in duration, then you would have a problem (3 x 2.5 AMPS = 7.5 AMPS which is greater than the PS rated output of 5 AMPS). The driver board is designed NOT to have that happen. Apparently, it does a decent job of power management.

If the power supply does not have any surge capability beyond its rated current, then you could have a problem. The power supply does have some surge capability though I do not know how much. A few days ago I measured the current on my setup (cutting air) with all three axes in rapid movement (back and forth) and did not see the INPUT power go beyond the PS limits. By the way, many power supplies (especially cheap ones) get very noisy (electrically) near their rated capacity. Simple switching power supplies have in fact been notorious for this. My supply from Xylotex looks very clean electrically.

If the power supply does not react fast enough in delivering current (as load changes/increases), then you would have a problem. Looking at the Xylotex power supply using a current probe and o-scope, it clearly reacts fast (at least the one I have).

So, your mileage may vary depending on your particular setup. Having a power supply of greater current capacity than necessary is generally a great thing.

I was already lining up a parts order for a much beefier supply myself before I got my setup adjusted. For the time being, I will stick with what I already have.

This by the way is not meant as an endorsement for the Xylotex approach/products. I have so little operating time under my belt that I would not offer same. In the future, maybe I will.

Regards to all,

George

This is what is in the Gecko Manual Starting on page #10:

--------------------------------------------------------------

POWER SUPPLIES
The choice of a power supply is determined by voltage, current and power supply type, i.e. switcher versus linear regulated versus unregulated and purchased versus in-house designed. By far the most problematic factor is voltage, so we will leave it until last.

The easiest factor in choosing a power supply is its current rating. The current rating of the supply is based on your motor choice. The drive will always draw less than 2/3 of the motor’s rated current when it is parallel (or half-winding) connected and 1/3 of the motor’s rated current when it is series (or full-winding) connected. That is to say, a 6 Amp / phase motor will require a 4 Amp rated supply when parallel connected and a 2 Amp rated supply when series connected. If multiple motors and drives are used, add the current requirements of each to arrive at the total power supply current rating.

-----------------------------------------------------------------


I kinda understand Xylotex thinking, but i do not neccessarily agree with using the min. power supply, More amps is always better because like most electrical, they only pull the amps it needs no more, so that being said I will always use a PSU with extra amps.

Glad you're working it out David. Can't wait to get my xylotex kit, multifunction card and computer, maybe all by this weekend. Got the rest of my mdf delivered this morning. I'm going to to rip it up, glue it to my torsion box, prime it and finish the gantry while it dries. My plans are to get everything ready for the electronics by saturday and I should have a full weekend of just playing around with the motors/electronics :D. Quick ?. I'm going to go with a sep. case after your experience, any idea on what you're going to use? I was thinking a small ITX case, anyone have any suggestions? I've seen people even use wood but I would like to stay with metal with a vent for a fan built in. I'm going to use my older router table cabinet for the computer stuff to be housed in. It's painted black and is pretty much perfect for holding a tower and wide enough for a slide out keyboard ;). Glad I moved it to my table saw extension, I knew it might come in handy. Thinking of throwing on glass or metal mesh doors and putting an air filter on the back where there will be a vent keeping the tower and controller pretty much dust proof.

Joe,

If I had not already bought my stuff before David's possible power issues became apparent, I would have gone with a higher current rating PSU. I may yet. Another axiom in EE is to avoid running power supplies near their design limits. Folks generally suggest running at no more than 70%. Based on measurements so far, I think I am near 83%.

I will now know what to watch for!

George

George/ Joe thanks for all the info, very educational.

I think I will try to find a replacement power supply with higher amps, hopefully something similar to the one Xylotex suppplies. If anyone comes across something suitable, please let me know.

Brian, I have already got the same plastic case that HobbyCNC recommend so I shall probably use that.

Thanks

Congratulations David. I'm glad to see you have your problems corrected. I have the same Xylotex 269 motors and had gotten nervous. Ready to see some new movies with the machine cutting.

Will do.

Busy today building the controller into a case.

New PC should also turn up today.

David

Will do.

Busy today building the controller into a case.

New PC should also turn up today.

David

Man, i am so looking forward to your machine working like a champ for you.

Joe

Me too ;)

Made good progress on the new controller box today should have it finished tomorrow.

New 3Ghz P4 PC turned up today so that is now loaded with Mach 3

Nice david, my computer is coming tomorrow, yours came fast! Haven't heard from xylotex or cnc4pc yet, hopefully they are prompt shipping it out as well... just glued one 1/2" skin on tonight.. reminded me how I need more clamps. I basically used cauls since it was a wide surface and it saved on only a clamp for each side. Used 1" staples where I ran out of clamps. It held down well. The weather is going to delay my build a few days, the temp. shot down, it's pushing it, even for primer. I'lle do 50 till it dries and then let it cure inside but 25 is really crossing the line. I mean, I might as well not prime it at that point. Any thoughts joe or david on the skins? I primed almost all the inside ribs well but wondering if it's worth the extra effort time and paint to do the insides of the skins. Def. will prime the outside though.

I am lucky both NewEgg and Xylotex are in CA so I get fast delivery.

I did not paint the inside of mine.

All my torsion boxes do not have paint inside them.

Yeah I have a distribution center near connecticut, in new jersey so they say 1 day ups and it will be here. Paid the extra fee they charge to have it rushed so I could toy with it this weekend :). Now all I need is a monitor for it heh. I won't paint the inside then, screw it lol. Did xylotex email you with a tracking # or cnc4pc? Haven't heard anything from them other than the paypal payment email, usually companies confirm. Time to glue the other side, be back in a bit.

All my torsion boxes do not have paint inside them.

Yeah, beyond aesthetics I really wonder how much paint maintains the integrity of mdf. Edges def. though. Sometimes we rush solid wood stuff to get sealed because it's not an engineered product, but mdf is fairly stable, especially in your design. I guess I was just trying to out-do david in painting it or atleast be up there but it seems impossible to do. :confused: Now, if this is what dave produced before he cut any parts with it, I can't wait to see the mods he works up. I better catch up, brb! :)

David, got my hp today, man is that thing a sweet deal. Heres a cam phone pic of it with my other desktop's monitor. All I need now is a dedicated monitor for it. I really dig LCDs and never want to go back to eye pinching crts. Now that I found you a good deal on a pc have any ideas on a good deal for a lcd :D? BTW, did you know it had built in speakers? Kinda spooked me out when it booted up heh.

Pic

Congrats!

Do me a favour and load Mach 3 and run the driver test and tell me what you see. My driver test looks odd.

By odd there is a step in the line on the graph of the number of pulses, not a spike but a step from lower pulse up to higher.

I completed my controller and it seems to run the motors much better using my old computer, but runs badly on the new one which I think has something to do with what I am seeing on the driver test.

Don't understand why its not a straight line. This is a brand new 3 Ghz PC with nothing else loaded on it.

david, going to put mach 3 on now, give me a few. And yeah if it's not working that's odd, this computer is pretty solid in terms of specs. I'm glad we have the same thing, it will help to determine a lot of issues ;). Checking now.

Here is mine from my machine, AMD 2400+, 1.67mhz 512 mem.

Yep, that's how it looks when I put it on my other PC, but this new one has a step from just above 32uS between pulses and just under 48 between 0 and 200 on the bottom axis.

have a picture? and what are computer specs, also did you do Optimize XP steps from mach3 site?

i did not have to do it much some do.

http://www.machsupport.com/artsoft/downloads/downloads.htm

joe

I'll take a picture tomorrow.

OPtimized with no effect. 3.1Ghz (with hyperthreading) 512Mb RAM, brand new HP, no other apps loaded.

Hmm its weird for me too, taking a screenshot now..

Try turning off hyperthreading in the bios. I've heard in the past that it could cause trouble, although I haven't heard anything recently.

Thanks Gerry, I wondered whether it could be a problem, I will try that tomorrow, bp092, could you try it and see if it has an effect.

screenshot of driver test..

I'll take a picture tomorrow.

OPtimized with no effect. 3.1Ghz (with hyperthreading) 512Mb RAM, brand new HP, no other apps loaded.


no pic needed, just hit print screen and paste it into paint, put it on a usb flash drive and put it on your computer with internet.. btw on that topic, are you going to add a lan card? I was thinking of a wireless g usb one but I hear they are unreliable and might just get a full on wireless card to connect into the mother board.. I'm pretty sure the comp will support it, it has 2 slots empty anyways..

screenshot of driver test..

you need to wait until you get the line to take a picture, or screen capture did not get it.

no pic needed, just hit print screen and paste it into paint, put it on a usb flash drive and put it on your computer with internet.. btw on that topic, are you going to add a lan card? I was thinking of a wireless g usb one but I hear they are unreliable and might just get a full on wireless card to connect into the mother board.. I'm pretty sure the comp will support it, it has 2 slots empty anyways..

I use a usb wireless on mine.

another test..

You beat me to it Joe.

bp092, its already got a lan card in it.

I use a usb wireless on mine.


that's what I'm thinking, so much easier :) going to order one tomorrow, other than that the computer will be pretty much barebone enough to run.. don't want to clutter it up with any software either..

hmm, bpo92, that's not what mine looks like, your looks perfect.

I may do a rebuild on the machine tomorrow and start again from scratch.

I assume you loaded the latest version of Mach 3

Make sure the network speed setting is not set to auto. That can interfere with Mach3. Set it to a fixed speed.

yeah I think it's lan ready but not wireless :( and I'm all wireless, I can hook it up but it's easier in my basement to just go wireless. Using wired to get everything I need on it though ;)

THanks again Gerry, I will try that.

How much does the pulses per second vary by? My $40 Ebay 1.1Ghz only varies by 2 pulses during the driver test.

another test..

these numbers are lower than may 1.5 gig machine.

david just did a fresh install from their site since I didn't have the installer exe on my laptop anymore, check out the latest build...
http://www.artofcnc.ca/Mach3VersionR2.00.037.exe

Yep that is the build I have.

Here are 2 pics with the lan set to 10Mbs

Could the problem be caused by "dirty" ac power from my wall socket?

How much does the pulses per second vary by? My $40 Ebay 1.1Ghz only varies by 2 pulses during the driver test.

I agree with this mine varies by 2 max, mostly clicks one.

I'm not all that into mach stuff yet, so the screenshot is all for you, I really don't even know a whole lot of what those numbers mean :P

Yep that is the build I have.

Here are 2 pics with the lan set to 10Mbs

Could the problem be caused by "dirty" ac power from my wall socket?

David that is bad. you need it to look more like mine.

Do you have quicktime on it by chance? Quicktime is BAD.

mine varies by only a few, maybe 3 max is that bad?

david, might consider a fresh reinstall with nothing, hp added some crapolah I see

I agree with you Joe, my CAD machine looks like yours. It makes no sense that bpo92 looks fine and mine does'nt as the machines are identical ordered from NewEgg within 2 days of each other.

That's pretty much what I have. Tomorrow, just in case I will do a fresh install of the OS and Mach and run the machine from a different wall outlet.

I agree with you Joe, my CAD machine looks like yours. It makes no sense that bpo92 looks fine and mine does'nt as the machines are identical ordered from NewEgg within 2 days of each other.

yea, go to add remove programs and remove anything you do not need.

lol man david is having a tough time with this, david, I've put next to nothing on this thing yet and fooled with 0 settings, try putting it back to where it was at fresh install in the control panel and do a test, might have to do with something you installed that affected the settings somewhere along the lines

Any antivirus stuff running?

No quicktime and already removed the likes of MSN, Media player etc.

Also remember BP092 has the same machine with nothing removed and is not seeing the problems (maybe I am cursed ;) )

I did load Firefox 2, but I cannot imagine that would cause a problem.

No antivirus running (did come with machine but not loaded).

All I can do is re-build the machine from the restore discs and see what happens

if nothing else, switch machines, maybe this will run the small mill with no problems. but it should be running fairly well,

switch machines? but I'm not even running the machine, just the driver test? if it's not software related maybe he has defective hardware, but it is highly unlikely.. just weird since we both have the same thing in the same timeframe with the same variables.. weird. David, does your cnc router not want to get dirty or something?

Well you made me laugh bp092, perhaps thats the problem my router has become a primadona and does not want to get dirty :)

Well I just had to see if I could resolve the problem tonight, so I did a complete reformat and restore back to factory settings, loaded Mach 3 and still the same. Tried a different power outlet, still the same.

I have asked for help on the Mach 3 forum, but unless anyone comes up with some bright idea I am totally stumped and can only imagine it is some weird hardware issue.

Failing any suggestions, I will swap the machine over with my PC that I use for all my CAD work. It is a 2.4Ghz and has lots of apps on it but when I just loaded Mach 3 the driver test looks normal.

Man, I thought building the CNC Router would be the hard part, but that was easy compared to all the electronics problems I have been having.

David,

Have you tried using Windows Task Manager? You may have a process running that is causing excessive CPU and memory usage. Try watching the Performance and Process screens. I've been watching the Process screen for a few minutes, granted I've got all my security stuff running but I did notice a couple of items going from around 250k mem usage up to 3000k or higher then falling off. In watching the Performance screen I noticed on a few occasions the CPU usage spiked from 0 or 1% all the way up to around 80% then immediately drop back to 0 to 1% range.

Just a thought maybe you'll catch something that's causing the problem.

You might want to look into this.

http://www.cnczone.com/forums/showpost.php?p=220860&postcount=7

ccsparky good tip I will check that.

Gerry, thanks I will check my bios today, but still strange that bp092 does not have these issues, I guess it's possible that our bios may be set differently.

David,

Switch to the DOS based TurboCNC machine controller software. Try that and see if you still have problems. Download at http://www.dakeng.com/turbo.html

Dave

Okay so I give up with the new PC having tried everything myself and everyone else has suggested to no avail.

So before I cut my wrists ;) I went back to using my original 1.4Ghz P4 PC that use to have the controller built into it.

I now have the controller in a separate box with the power supply and the CNC4PC card. I have bypassed the CNC4PC card to simplify my tests and although I think the machine movements may be a bit better, I cannot get anything reliable out of the machine.

So moving backwards, I took 3 135oz/in steppers back of my Sherline Mill and along with the sherline controller I connected them to my 1.4Ghz PC (the same one the Xylotex board was connected to. The last time I tried the sherline setup I used the PC that the sherline controller was connected to as well.

The results a very good, I can run all axis at 60 velocity and 8 accel totally reliably and the sound good. So this means I can rule out the PC as a problem area, so that leaves me with the Xylotex controller and cabling. To reduce any cabling issues I had already removed my extended cabling from the loop and was just using the cables made up by Xylotex.

I have attached a small quicktime movie of the y and the z in motion with the sherline and I think you will agree it sounds good.

The only other thing to be tried on the Xylotex is the power supply which I will test in a minute with my two PC PSU.

Beyond that I am getting to a point of looking for a different controller, possible the HobbyCNC one which I think I can use with the 425oz/in steppers I recently bought from Xylotex which are 8 wired unlike the 269 which are 4 (Joe can you confirm?)

David,

Just got back from my business trip. Sorry you are having such issues.

Have you thought about driving the small motors from the Sherline with the Xylotex setup as a test case?

George

Okay, so I wired the 2 PC PSU in series to get 24v 13a and powered the xylotex controller up. Put the 425oz/in stepper back on the z and as you can see from the attached movie it is **#*#.

So it does not appear to be power and I am having a difficult time believing it is cables as the only cable hocked up is the z-axis, so that leaves the xylotex card.

I would have to rewire them but I could do that. Also remember that I have run the xylotex with the original 269oz/in motors with the same problem.

It would be interesting and I guess the same test to hook to 425 up to the Sherline controller

David,

I definitely have heard that sound before. In fact, I can reproduce it at will with my setup by setting the max speed too high or binding the movement of any of the axes.

That sounds just like mine did with axis alignment issues. The sound starts with the motor actually attempting to spin up to fast which starts it missing steps. I could almost always get the axis to move in the 30 to 50 range but before fixing alignment, I got exactly that sound.

I will suggest that it is not necessarily the driver board.

G

Okay, so I wired the 2 PC PSU in series to get 24v 13a and powered the xylotex controller up. Put the 425oz/in stepper back on the z and as you can see from the attached movie it is **#*#.

So it does not appear to be power and I am having a difficult time believing it is cables as the only cable hocked up is the z-axis, so that leaves the xylotex card.

Start off with motor tunning at 40 and accel. at 15, then increase the vel. 10 each time. there should be no reason you can not jog atleast 80ipm.

we have a few machines that run that all the time.

I would think also not the controllor.

(Make sure leadscrews are lubed also again)

Well I will try that again, but I have tried pretty much all combo of accel and vel. Also remember that the machine is working at 60 and 8 with the sherline

David,

Shooting in the dark here but when I was having alignment issues, I could generally count on good results when my axes were at mid travel (mid 1/3 for each). I could almost always get fast movement and good acceleration until I was in either of the outer thirds of movement range.

One of the tests I did was to back off tightness in all bearings (lead screws, anti-backlash and slides - so that each was "sloppy/loose." When results improved, I deduced it had to be alignment issues. All the while, without the lead screws in all axes would glide easily by hand AND with the lead screws in, I could turn all of them by hand (fingers actually).

As I thought about it, I tried to "feel" if any of the lead screws varied in how hard they were to turn through 360 degrees. While I could not testify they were not all even around the 360, my belief was that in each case of a trouble axis (the exact sound you are getting), there was distinct variation in ease of turning.

If you refer back to one of my previous posts, you will read how I remedied the situation [bearing seats for the lead screw] and now have movement for all, clean and 80 IPM/10 accel or better for all.

George

Just tried 40 and 15 still locking up.

I dont think it is an alignment issue as I checked all that and besides the 135 oz steppers and sherline controller are driving it nicely at 60 and 8 (see video)

David,

Not to dispute....the smaller motors may not be as capable of acceleration as the larger ones are. You may recall I stated the driver board purposely limits current. It is within the realm of possibility the motors are trying to overcome resistance (binding in table movement) and stalling because alignment will not let them accelerate properly (forcing them to demand more current than the board will supply).

Do you have access to an o-scope? I could explain how you could measure and tell fairly quickly if you are hitting current limits. You may in fact be able to measure directly if you have a volt/amp meter that responds fast enough. Let me know if you want to discuss same. I would be happy to chat with you via telephone if you want.

George

But if both the sherline motors/controller and the the Xylotex motors/controller are both set to the same accel and velocity and the Sherline provides a good result does that make sense, or are you saying that the sherline is not really achieving the same accel and velocity.

Unfortunately, I do not have a o-scope.

I am going to see if I can wire a 425oz/in stepper up to use the sherline controller and test that

Beyond that I am getting to a point of looking for a different controller, possible the HobbyCNC one which I think I can use with the 425oz/in steppers I recently bought from Xylotex which are 8 wired unlike the 269 which are 4 (Joe can you confirm?)


Sorry did not see the post, the 425 are bi-polar, and yes you can wire them to uni-polar they will run at 305oz, i have run my X axis with one using the HobbyCNC board.

Joe

I am going to see if I can wire a 425oz/in stepper up to use the sherline controller and test that

do you have specs on the sherline controllor? We will get this resolved sooner or later, we have a few people here for resources.

Thanks Joe, I should take a picture of the router at the moment, there is electronics and cables and tools all over it ;).

The specs are here http://www.sherline.com/8540pg.htm, what do you think?

David,

I dug into the specs and cannot tell based on the links I visited (a dozen or so) that list info about the Sherline supplied motors if my theory has any validity. I most definitely did not see anything that would invalidate the theory though.

Fact: The acceleration rate available on two different designs of motors will almost always be different.

The acceleration rate you specify in Mach3 is the rate at which it increases the pulse rate sent to the driver. The response of the driver and motor are whatever they are. They can indeed be snappy and "obey" the Mach3 pulse acceleration rate or they may not. Even if they are "slow" to get going, they will not necessarily stall. It is a function of the driver motor combination. Unfortunately I do not have enough engineering specification data to look at to make a conclusion.

The starting torque available for a stepper motor will always be different than the torque available when it is in motion already. In other words, some may be hard to get moving from stop but have loads of torque available just after they start any movement. I have my suspicions about the 425's in combination with the Xylotex driver. Steppers of course are more powerful (more torque) at lower speeds than higher speeds.

Again, shooting in the dark. The fact you can get a lower powered setup to work well when the more powerful (supposedly) system will not is very curious. I remain extremely puzzled about what I see and hear in your video clips. I fought with what looks and sounds identical to me for many many hours. As I have stated before, adjustments and bearing surface truing got mine to behave.

Just for giggles, please describe exactly how you have the wiring done from the driver board to the motors. Please include motor wire colors and describe your cable run (8 singles going to 4 pairs near the motor or near the driver board).


George

It is very baffling, I currently have the sheline setup on the y and the xylotex on the z and by swapping the printer cable between them I can quickly compare settings. I have just been running the sherline at 70 velocity and 8 accel and can see on mach 3 that it is reaching 70 and it runs perfect. If my xylotex was running with those settings I would be perfectly happy.

Okay so the cables, from the motors there is the usual 10" or so long pigtails, which I put in loose plastic sleves to hold them together (same as Xylotex did on the 269 motors).

These are connected to 4 pin molex connectors and as I did not have any spares, I cut them of the 269 motors leaving a couple of inches of cable, which I then soldered and covered each one in cable wrap. From there a male molex connector plugs in and uses 18AWG 4 core none shielded cable to the controller where it has crimped on pins to go into the controller. This cable was made by Xylotex not me. I have extended the cables with more molex and 22AWG 4 core non shields cable but for the sake of testing I have these out of the loop. All other limit switch cables are disconnected.

Each motor has its own 4 core 18AWG cable

So in summary the only part of the cable that I effectively touched was grafting the molex connectors onto the motors. I am pretty sure the solder joints I did are good not that I am an expert, but I applied solder to both sides of the cable first then melted the two together making sure the solder flowed.

I need to work out if I can, but I would like to wire one of the 425 motors to the sherline controller and see how that behave.

By the way, I dont seem to be the only one having such problems check out this thread http://www.cnczone.com/forums/showthread.php?t=30095&goto=newpost

David,

I too noticed the other thread. Does make the Xylotex suspect doesn't?

I put the loose 425 motor wires into short sections of left-over tubing from the z axis bearing slide build. I hard wired (mechanically stable twist connection, solder, then heat shrink tubing over the joint) the connection at the end of the pigtails with my longer cable. My 8 wires to four pairs is at the motor end. The cable I used is 18AWG 4 wire shielded (foil with a drain wire). The shield is connected to the chassis on the driver end and NOT at the motor end.

By the way, 22AWG is generally NOT appropriate to deliver power at up to 2.5 AMPS. It will in fact be possible to get significant voltage drop depending on the length of the cable. When you do get to the point where things are working with the shorter setup (you will!), do yourself a favor and get larger guage cable for the longer setup.

Over the next couple of days in between my regular job activities, I will try a different Xylotex setup (the 3 axis version with the 269's - my future mini-lathe CNC setup). I will also try the servo setup (3 Gecko 340's w/400 oz/in peak servo's) I have for my mini-mill. I will purposely stall the motors (by binding the axes) as I can now with the present Xylotex setup.

That will give me some comparitive data that may reveal something. I have wanted to get to that anyway just to see the differences.

At the moment, I have no other suggestions.

George

THanks George your help has been much appreciated.

I think just out of interest I will put a 425 stepper on my Sherline Mill and run it from the Xylotex and see how it behaves.

Joe I went ahead and ordered a HobbyCNC kit yesterday as I need another avenue of testing as I really would like to get my Router working. I will order the case that HobbyCNC recommend, but I think I will get the powersupply from that ebayer you referred me two. I will look for one similar to yours.

I intend to use it with the 425 steppers

David, I should have the xylotex kit today so I will test it this weekend. I will let you know of my results. Maybe I can help to figure out what is going on, if its the kit, the computer, or what ever. Haven't heard a word from cnc4pc, were they prompt or did they contact you first of the shipment? I haven't even gotten an email from them.

bp092, Arturo at CNC4PC usually responds to me in a day or so.

Well I put one of the 425 oz/in motors on the Z axis of my Sheline Mill and hooked it up to the Xylotex board and you can see the results in the video.

The setting for the first run are the same that I use for the Sherline motors and controllers and although it runs without stalling I think you will agree that it does not sound very smooth.

The other two runs on the video speak for themselves.

Check out the video here http://www.digitaloceans.net/workbench/sherline%20test.mov

bp092, Arturo at CNC4PC usually responds to me in a day or so.

Well I put one of the 425 oz/in motors on the Z axis of my Sheline Mill and hooked it up to the Xylotex board and you can see the results in the video.

The setting for the first run are the same that I use for the Sherline motors and controllers and although it runs without stalling I think you will agree that it does not sound very smooth.

The other two runs on the video speak for themselves.

Check out the video here http://www.digitaloceans.net/workbench/sherline%20test.mov

Which driver board did you get from Xylotec, 3 or 4 axis, have you tried to switch the axis on the board, if you have the 4 axis use the extra axis for the z, maybe something wrong with one of the axis on the board?

just a thought.

I got the 3 axis.

I ran it on the x axis and it is the same as the z

After another fruitless day including frying my sherline controller when I hooked it up to the 425oz motors I have decided to go back to basics.

After putting a 425 on the x axis (always my smoothest axis) it runs fine, I therefore need to go back and strip down my z axis and check alignment again.

I think I am going to go as far as taking the z axis slide off so I can see the acme nuts and backlash adjuster (I hope I can get the u-bolts back on with the drill rods in place).

On the y axis I know my leadscrew is slightly bent so I shall order some more.

David,

What mode do you have the 425's wired? Bipolar series or Bipolar parallel.

Rick Kelley

David,

I have a sample of my system running posted at my .mac homepage

http://homepage.mac.com/gtsullivan/FileSharing1.html

Just to validate that it is possible to run a Xylotex w/425's.

Pardon the poor production values.

George

After another fruitless day including frying my sherline controller when I hooked it up to the 425oz motors I have decided to go back to basics.

After putting a 425 on the x axis (always my smoothest axis) it runs fine, I therefore need to go back and strip down my z axis and check alignment again.

I think I am going to go as far as taking the z axis slide off so I can see the acme nuts and backlash adjuster (I hope I can get the u-bolts back on with the drill rods in place).

On the y axis I know my leadscrew is slightly bent so I shall order some more.

did you permanently place those rods in there? mine are tight and don't have any movement but I can get them out without much effort.. I just slide them out a quarter of the way and slip the slide assembly off

David,

I have a sample of my system running posted at my .mac homepage

http://homepage.mac.com/gtsullivan/FileSharing1.html

Just to validate that it is possible to run a Xylotex w/425's.

Pardon the poor production values.

George

Looks like the Machine is preforming good at 100ipm. are you having a build log? :)

Joe

Joe,

I plan to post & video what I have done that is out of the ordinary.

The lift, the knock down hinges on the gantry, my cable chain install and the new dust collector I have designed. May get done this weekend. Up to the point of the standard base assembly, mine has been unremarkable. The stuff after the base some may find interesting. In response to some of David's posts, I did discuss in his thread what I did for alignment and truing for the bearing seats for the leadscrews. I had a bear of a time getting mine to run reliably at 100 IPM. In fact, my first start sounded just like the stalling that David documented in one of his videos a day or so ago.

I did start a thread with some background some time ago and will add the above to that here within the next few days.

George

Wow just read this entire thread... what a morning... this issue is IDENTICAL to my issue that David points you to. To add some information on things I have tested:

Remove everything from the Z axis and just run the motor hocked to the lead screw. Problem still exists. David I think you are headed to test this out now.

I will get it working fine for a test senario then come back and poof it is not work any more. I think this has happened to me three times. I take my lunch hour try something new working fine at 1pm when I go back to work.... When I return to play after work, the thing is back to the not working again at one of the speeds and I did not do a thing but turn the controller off and back on and run my test code which is:

g01 z0 y0 x0 f100
x1 y1 z-6
x2 y3 z0
x3 y5 z-3
x6 y1 z-6
x9 y2 z-4
x12 y4 z0
x15 y3 z-6
x17 y6 z0
x18 y18 z-6
x24 y12 z0
x28 y18 z-6
x30 y 21.5 z0
y0 x15 z-6
x0 y21.5 z0
z0 y0 x0 f100
m30

I have removed noise from the issue by disconnecting all the other motors and only leaving the Z axis running... no load should mean no noise on the line. Problem still occurs even with only the lead screw attached (assuming nuts are tightened down around motor base)

My set up is the 4 axis fully built box from Xylotex (I bought because I really did not want to play with any electronics). I have the 269oz in setup
Limit switches are in place but no power to them yet.
Controller is out side my PC.
PC is 2.6GHZ with 2GB RAM (but I have tried 3 others)
My controller is directly connected up to the PC's parrallel port. I have the breakout board ordered but not hear yet.

One thing I have noticed that appear to eleviate the problem is loosely mounting the motors. If the motors are not bolted down the problem rarely exhibits its self so I am presently testing the following:
LoveJoy couplers. Well I think I can wash that out because David has them in place on Joe's machine. I started testing last night and it still stalled.
Rubber washers on either side of the motor mount. Last nights test of about a 1/2 hour were showing good results on this one (even with them tightend down well). Only problem is the tape between my driver and heat sink is shot and I don't know what to replace it with... going to swap axis today with the A axis to get it going (At least I think I can do this)

Before I say this, my electronics knowledge is limited (about the level of Davids from what I read). While at first I was thinking it was power as you guys have been trying to identify with the limited Amps. Would it not only be a problem when the amperage becomes limited (ie all motors are running) and not when just one motor is running and has all the power required to meet the needs you guys have identified. In my testing I can break it down to a fedrate on the axis and only have the lead screw attached... which by the way is only going through 1 bearing and runs PERFECTLY straight (no wobbling = no binding = barely any load). At this point my testing leads my limited knowledge of electronics and electricity to believe that this is not a power supply problem with only one axis.

Also when using the rubber hose coupler in the Solsyva design if you unclamp the hose and then reclamp the hose the point at which the failure occurs usually changes by a bit. So F22 might have been the sour point then F25 is after loosening and clamping the unit.

David,

What mode do you have the 425's wired? Bipolar series or Bipolar parallel.

Rick Kelley

I don't actually know Rick, I just followed the wireing diagram for a 8 wire stepper on Sherline's site

David,

I have a sample of my system running posted at my .mac homepage

http://homepage.mac.com/gtsullivan/FileSharing1.html

Just to validate that it is possible to run a Xylotex w/425's.

Pardon the poor production values.

George


George looks very good.

To rule out any other differences could you send me a copy of your Mach 3 .xml file you are using?

David

did you permanently place those rods in there? mine are tight and don't have any movement but I can get them out without much effort.. I just slide them out a quarter of the way and slip the slide assembly off

They are not permantely installed in that I fixed them in, but I did have to use a mallet and some brute force to drive them in so I doubt they are going to come back out without a fight.

Buzz9075, it is at least reassuring that I am not the only one experiencing the problem.

Not that I understand the physics behind it, but I have seen in a number of places that the Xylotex controller has a prepondancy to create resonance which cause the motors to not function efficiently. I think it is the resonance that we hear. When a stepper is working correctly it moves smoothly and sings (in fact I have seen poeple write music with g-code).

From what I see everyone but one person is having a problem with the Xylotex system... so definitly we are not alone. A lot of people are watching my thread on this. Figured seeing as you are working on it I would post the initial results here.

OK this mornings testing is looking good for rubber washers. I am calling it a break point for an hour or so for two reasons... play some hockey with my son in the back yard and two ... what I have seen before it is fixed turn stuff of and back on a while later and it is broke again.

So my tests this morning were based on rubber washers that encase my motor mouse. Like the ones you use to go through the case with wire.

Attached is my test results and so far these are the best I have seen. While I am still hearing the moaning I am not getting as much.

From the results I have determine I need to do the following
Adjust the top end of my z axis
Decrease my acceleration a little
Determine why I travel 6 1/16 when I only ask it to travel 6".

I will post picture of my set after I come in... my son is pull my hair to get out side.

NOTE: all tests are air tests.

The test for this attachement are as follows:
g01f5
z0
z-6
g01f10
z0
z-6
g01f15
z0
z-6
g01f20
z0
z-6
g01f25
z0
z-6
g01f30
z0
z-6
g01f40
z0
z-6
g01f45
z0
z-6
g01f50
z0
z-6
z0
m30

Buzz and I have been responding in another thread.
I have a MAXNC 15 OL (Junk, dont buy one)

it has 20 TPI screws, I have installed the Xylotex driver, PSU and 269 motors. I have battled the resonence issues for months. When I say I have tried everything. I mean just about everything. i asked alot of questions and machined alot of adapters, couplings, thrust bearings ect.
When doing my purchasing for the driver kit I was told that with this kit on simular sherline and Taig machines people were getting 40 to 60 IPM. So i was stoked. I could get 60 IPM but of course the resonence would cause the machine to randomly loose steps. I got the bald spot to prove this :)

What I have found that at least makes the machine usable is a max 20 IPM in mach 3. I have had to lower the Vref settings in all the axis to remove the garbage you hear from the motors. Seeing as I am cutting mostly wax and MDF this has not been a problem. I have not tried cutting any allows really.

It has been brought to my attention on the Mach forums that this PSU,Driver, motor combo is not the most efficient due to the lack of power going to the steppers. The 24v PSU is in the bottom end of the power requirments to effiecntly run the 269`s. The limits on the driver is alos a crippling factor. (AGAIN 20 TPI screws, I know that if i went to 10 tpi I would in fact increase rapids) but still the resonence would exist I beleive.

I am not spouting facts here, just theroies, so if someone knows something that I do not. please SPEAK UP! Cutting wax ring molds... takes forever at 20 IPM :)
That and I like tinkering.

Hope this info helps
Robert.

I am uploading updates to my web page which include pictures of the rubbers I have been working with. My last tests did a full table test which seldom get through without failing the z at some time. It ran 3 times before the Y axis failed. It had the lovejoy connector on it. So it was better than before (usually stall once a pass). So I am short rubbers for the Y axis... will get some while I am out this after noon to complete the Y axis with rubbers and see how things goes. if this works it would mean that I would need to isolate the pushing of the axis against the motors so that the rubbers woudl not take the back pressure and loose accuracy in the rubbers... and still reduce the tendancy for it to stall. Should have more test results tonight.

Pictures should be up in 5 minutes or so they are jsut compiling the web page now.

Helps if I post the web page again :)
http://74.104.179.252/thephillips/PhotoGallery/CncMachine/CncMachine.HTML

Okay guys I have totally stripped my z axis down to just the leadscrew and bearings, I have confirmed by hand before putting the motor back on the the leadscrew spins freely. I reconnected the 425 and guess what....the same problem. I definitely concur that resonation seems to be the issue.

David try backing down your VREF settings (WITH THE POWER OFF!!!!!)

Keep backing it down untill the resonence is gone.....


Then adjust your motor tuning to suit.

This will at least make it work.

Done that, everything from 2.25 up to 3.6 with no change

keep going down, I think I have one of mine set on 1.6 each axis is different due to load ect.

I am not famiiar with xylotx but, Are there any gains adjustment on these drives?
If you try to command the axis to move and it stalls, what happens if you were to assist the axis..by "carefully" trying to spin the nut or ball screw by hand at the same time....PLEASE watch your fingers if you do this!!!
If the inrush current is insufficient to get the axis moving you maybe saturateing the motors (100%) amps.

I am not famiiar with xylotx but, Are there any gains adjustment on these drives?
If you try to command the axis to move and it stalls, what happens if you were to assist the axis..by "carefully" trying to spin the nut or ball screw by hand at the same time....PLEASE watch your fingers if you do this!!!
If the inrush current is insufficient to get the axis moving you maybe saturateing the motors (100%) amps.

Most of my troubles are at random points. The motors have no problems getting going. i can be 1/3rd 1/2 or almost all the way thrue a program and it will loose steps. Totally random!!!!!

Anyone have any simple g-codes of 2 and 3 inch arcs with z movements in them? Something to totally work the whole machine for testing?

So carry on with the testing I unscrewed the 425 from the mount and tested just holding the motor of the mount and it is definitely better. Then as the shaft on the 425 is longer than the 269's and therefore touches the lovejoy spider I put the 269 back on and bolted it down and can run at 100/2.5 doing G1/G0 rapid up and down 5" at 100ipm

Are you side loading an ACme Screw? They tend to bind when side loaded, unless you purchase a centralizing acme screw and nut assembly...just a thought. what type of cut/depth/speed/feed are you performing when it stalls or skips steps? Has your cutter become dull, requireing the motor to work harder?
Seems to me that the guys that have dis-assembled their machines to just the z axis and motor are experiencing electronic isssues, yours sounds more mechanical to me?

Are you side loading an ACme Screw? They tend to bind when side loaded, unless you purchase a centralizing acme screw and nut assembly...just a thought. what type of cut/depth/speed/feed are you performing when it stalls or skips steps? Has your cutter become dull, requireing the motor to work harder?
Seems to me that the guys that have dis-assembled their machines to just the z axis and motor are experiencing electronic isssues, yours sounds more mechanical to me?

all my testing and I think I speak for most everyone that is still in the "TESTING" phase is all air cutting. no tool load. And these are at rapid movments.

here is a neat little test that I have come up with in MACH 3
set your acceleration rats really low. 1 or 2 knotches above the very bottom.
Set your vel low and work your way up. I start with 20 IPM because I know Im safe there.

set and save your setting, then jog the axis. It takes a bit for the motor to reach speed. If your VEL setting is to high you will hear the motor loose steps before it reaches max vel.

Ok im playing with the machine today. Here is a quick thing I just noticed Hope it helps

Doing my testing above on my X axis.
VREF setting is 2.3
Accel is .19921875 (Very low)
Velocity is 30.33

Fast jog test has the motor squeeling and missing steps within 5 seconds. You can hear the resonence build up untill it squeels. (Locks up the motor)

Everything the exact same EXCEPT for VREF setting I took it down to 1.89
and it will JOG and run test (Lots of back and forth motions) stable.

David glad to see we both have the same results, atleast I am not loosing my hair due to my mistakes. So this is what I found.... Whit the problem happening, loosen your motor mounts so that the motor can move freely on it mounts and test again... you should find that the problem goes away or atleast is reduced significantly... I rarely have a problem when my motors are just flopping around.... this is why I have been testing with the rubber mounts.

As well I NEVER EVER EVER have stalled the X axis and it is belt drive... So if all else fails I might just test with changing both X and Y to belt drive systems... if only I know of a local store in Ottawa that carried this stuff I would go snope around.

OTTAWA? that sounds like a place in Oklahoma.

You have just solved your own problem.

The belt drive is what is curing your resonence problem. is there a timing difference in the pullies? Gearing? say 2:1 and if your running the Z axis direct coupled and trying to get the same preformance (SPEEDS) as the X.... without the gearing... then I think you need to cut your VEL in half.

Remember I am on a mini mill, not a router table. So if it sounds like I dont know your setup... LOL your right!

So at low speed all is ok? but at rapids steps are lost...

20 ipm is under the rated 80% critical speed of a 1/4-20 acme screw, therefore you should be ok, the closer you goto say 40 ipm on a 1/4-20 acme screw the more you hit the 100% critical speed, (screws natural resonance) acording to the critical speed charts i have looked at.
Ac,e screws dont like to be shock loaded either, and going from 0 to 40ipm maybe to much for the nut to screw assembly to handle, causing wedging.

For refference on ACme Threads.........

http://www.nookindustries.com/acme/AcmeGlossary.cfm

Hope this helps.

So this is what I found.... Whit the problem happening, loosen your motor mounts so that the motor can move freely on it mounts and test again... you should find that the problem goes away or atleast is reduced significantly...

So giving it axial and radial freedom helps solve the issue?

ALSO Removing a ridgid direct mount and going to a belt system shows improvement...?

the way it was explained to me with a rigide collar...
the motor puts out vibrations, and the screw rotating causes vibration. With the connected rigidly together the vibration continues to build gives. (This is all to a point) now in you have resonence in the motor (Operatining it in its resonce range) then the vibrations amplify the resonence in the motor. Causuing the stall.
With belt driven systems you are seporating the motor and the drive line. The belt gets all the vibration. Or dampens it. Due to the properties of the rubber.

Nother way of acheiving this is with couplers of some sort. The ones i have made allow for the lead screw to move up and down and the shaft of the motor to remain stationary.
http://i82.photobucket.com/albums/j253/fixittt/MAXNC/Flex%20couplers/100_2065.jpg

Are you side loading an ACme Screw? They tend to bind when side loaded, unless you purchase a centralizing acme screw and nut assembly...just a thought. what type of cut/depth/speed/feed are you performing when it stalls or skips steps? Has your cutter become dull, requireing the motor to work harder?
Seems to me that the guys that have dis-assembled their machines to just the z axis and motor are experiencing electronic isssues, yours sounds more mechanical to me?


Not sure what you mean but I don't think I am side loading the acme screws.

What is a centralizing acme screw and nut assembly?

Only air cutting at the moment have not cut anything therefore the tool sharpness is not relevent.

Well I have gone from mechanical to electrical back to mechanical trying to troubleshoot.

Here is something else I have done. With my Vref set at 1.7V I could get a max vel of 35 IPM going to 37 IPM caused resonence and a motor stall very quickly. I then dropped my Vref to 1.5V and am now testing at 40 IPM and it seems pretty stable. Of course there is no tool load. But it has been running for about 7 minutes back and forth

So I have now put rubber gromets between the motor and the mount and I can run at 100/8 at a vref of 3.32.


You can see a video of the run here http://www.digitaloceans.net/workbench/269%20test.mov

Not sure what you mean but I don't think I am side loading the acme screws.

What is a centralizing acme screw and nut assembly?

Only air cutting at the moment have not cut anything therefore the tool sharpness is not relevent.

Well I have gone from mechanical to electrical back to mechanical trying to troubleshoot.

hi david, At first i was unaware that you guys were air cutting so please ignore my comments on tool sharpness.
A centralizing screw is just a tighter clearance between the nut and screw esentially, A general acme screw and nut tends to have more "slop" in it and can therefore bind much easier when shock loaded or side loaded.
Side load is just that, a force acting on the side of the screw and nut assembly (perpindicular to the way it is moving).
If you try to move a acme screw to fast right from rest it is possable that the initial shock loading can bind your assembly.

Resonance on the other hand is a fancy word for electrical vibration. You never want your amps and voltage to be at a point in the phase where they resonate, it will cause heat and ruin your drives or motors. This is why volt ref(vref) and gain adjustments exsist in drives, to tune out the amp and voltage phase I believe (correct me if I am wrong) that you do not want your amp and voltage to be converging at the sametime, normally one is ahead of the other by 90 degrees. adjusting the vref shifts the phase so they dont converage at the sametime.
What fixitt is saying is not only are you experienceing this resonace electrically, your acme screw itself, when turning is adding more mechanical vibration which amplifies the condition, causing miss steps and stalling. :)

Perhaps an upgrade to rolled ball screws would also help?

THanks for the explanation. Does anyone know where can you order such centralizing acme threaded rod and nuts?

Thanks again

xxx.nookindustries.com/acme/AcmeGlossary.cfm#ScrewCritical

if mechancial vibration is bad from the acme screw, why not spend a little more and up grade to cheap rolled ballscrews from misumi or Roton or Nook?

You could verify first this is the case, before laying out the cash, by doing what the others have done and place some rubber mounts between your motor mount and install a spider type love joy to aid in absorbing mechanical vibrations?

cheers

that is with a pitch screw of 10 is that correct?

Looks very very good! Sounds good as well. now why cant mine do that? at least at 50 IPM?

hi david, At first i was unaware that you guys were air cutting so please ignore my comments on tool sharpness.
A centralizing screw is just a tighter clearance between the nut and screw esentially, A general acme screw and nut tends to have more "slop" in it and can therefore bind much easier when shock loaded or side loaded.
Side load is just that, a force acting on the side of the screw and nut assembly (perpindicular to the way it is moving).
If you try to move a acme screw to fast right from rest it is possable that the initial shock loading can bind your assembly.

Resonance on the other hand is a fancy word for electrical vibration. You never want your amps and voltage to be at a point in the phase where they resonate, it will cause heat and ruin your drives or motors. This is why volt ref(vref) and gain adjustments exsist in drives, to tune out the amp and voltage phase I believe (correct me if I am wrong) that you do not want your amp and voltage to be converging at the sametime, normally one is ahead of the other by 90 degrees. adjusting the vref shifts the phase so they dont converage at the sametime.
What fixitt is saying is not only are you experienceing this resonace electrically, your acme screw itself, when turning is adding more mechanical vibration which amplifies the condition, causing miss steps and stalling. :)

Perhaps an upgrade to rolled ball screws would also help?

Glad i got someone around to translate my idiot ramblings. In other words "Yeah what he said!"



now as for upgrading to ball screws. Dont I wish! I just dont have the funds right now for that. Not after throwing all the money at it to get the machine back in a working state. Plus I am out of work right now due to a motorcycle wreck. Tinkering with this and learning the jewlery side of CAD/CAM is what is keeping me sain.

xxx.nookindustries.com/acme/AcmeGlossary.cfm#ScrewCritical

if mechancial vibration is bad from the acme screw, why not spend a little more and up grade to cheap rolled ballscrews from misumi or Roton or Nook?

You could verify first this is the case, before laying out the cash, by doing what the others have done and place some rubber mounts between your motor mount and install a spider type love joy to aid in absorbing mechanical vibrations?

cheers


I think we are cross-posting. Joe's design calls for lovejoys which I have had installed all along. I have just installed rubber grommets - see video.

THanks

that is with a pitch screw of 10 is that correct?

Looks very very good! Sounds good as well. now why cant mine do that? at least at 50 IPM?


Yes 10.

Now to put everything back together and see if I can still get similar results.

xxx.nookindustries.com/acme/AcmeGlossary.cfm#ScrewCritical

if mechancial vibration is bad from the acme screw, why not spend a little more and up grade to cheap rolled ballscrews from misumi or Roton or Nook?

You could verify first this is the case, before laying out the cash, by doing what the others have done and place some rubber mounts between your motor mount and install a spider type love joy to aid in absorbing mechanical vibrations?

cheers

here is an older video I did on my maxnc it shows exaclty what I (And several others) are up agaisnt.
Vref settings are 2.83
and as you can see and mostly hear. Resonence is a problem!

http://i82.photobucket.com/albums/j253/fixittt/MAXNC/Xylotex%20troubles/th_100_2093.jpg (http://s82.photobucket.com/albums/j253/fixittt/MAXNC/Xylotex%20troubles/?action=view&current=100_2093.flv)

Sounds familliar

WELL?????? does it work?!?!?!?!?!?!?! Or did the bald spot get bigger?

Still putting it back together ;) Taking the time to make sure everything is in perfect alingment

I am back, got more rubber washers for my Y axis, glad to hear they are working for you as well David. So if you do implement them you will need to ensure that any back pressure from you cutter can NOT be transfered to the motor or the motor will push on the washers and you accuracy is out the window.

For example on my lead screw I plan on putting a nut and bearing assembly on the far side of the wood that the lead screw goes through to from the motor to the Z axis. This way when you apply pressure down on your cut the force will stop there and not make it back ot the motor... so you really should be able to loosely mount the motor and keep the accuracy.

Will get back to you gusy after I complete my Y axis testing with both a rubber and some lovejoy :)

Just remembered I forgot to indicate, the gear ratio is 1:1 and the motor drives to leadsrews on the same belt. Check out my web link I list before it has lots of pictures of the entire machine.

Will get back to you gusy after I complete my Y axis testing with both a rubber and some lovejoy :)

Is that legal in Canada? :confused: Better safe than sorry. ;) Don't forget to clean up any mess when you're finished. :)

Seriously, though, you've got everyone watching this thread, and the others, to see how this issue with the Xylotex controller and the 425+ oz-in stepper motors is resolved. If I stay away for a couple of hours I find that I'm several thread pages behind. Glad to see you're making progress no matter how slow it may seem.

Keep up the good work.

While I still have lots more tests to run. I think I have a winner... the Y axis appears to be purring like a kitten with the lovejoy and a rubber. The machine is moving through the pattern no on its fourth pass and I have yet to hear even a sign of a moan from either the Y or Z axis. As a matter of fact I have heard some rather cool sounds as the system transfer directions.
Setting X 52/4 Y 52/2 Y 40/1

And I just notice my Y axis mount is not even on straight... I bet I put it on at a -10Degree angle from straight.

Next round of test is going to need to make sure it is coming back to where I sent it away from (back to the same 0,0,0)

I'll be back...

I am back, got more rubber washers for