CRP4848 with 1530 base

[allengambrell]

I have the machine mostly assembled and I am trying to do the motor tuning.

I am a little lost, it seems like I can get the velocity and acc set and it will jog at 100%, but then a few minutes later the motors might stall on the same setting. I can get the X axis to around 500ipm and the y to 800ipm, but then sometimes it might stall at 100%.

I have the a axis slaved and reversed to the x axis and sometimes one will stall and not the other, killing the alignment of the gantry. I have been putting the same values in the x and a for motor tuning, I a guessing that is correct.

[Euro3D]

Hi Allen,

What PC and Machine software (Mach or LinuxCNC) set up are you running.

You could be running into a latency issue with the PC, ie the ability for the pC to generate enough pulses per second. If you are running LinuxCNC there is a test you can run that determines if your PC has the ability to run the pulses at the required frequency.

I am running LinuxCNC on a pentium4 Dell and have seen 1100IPM rapids easily.

Cheers

John

[ahren]

Allen,

You might try reducing the microstepping on the drives and changing the tuning parameters in Mach accordingly as a quick test, as this will lower your required pulse rate.

You may also be running out of torque due to the high 15mH inductance in the motors you are using. This may limit your top speed somewhat, and if you are running near the edge of what the machine can do, stalls may occur seemingly "randomly". Does this behavior occur at lower speeds (300 IPM?). Also I'd suggest lowering acceleration and see if this helps, since this translates directly to how much force the drive has to put out to move the way you want it.

John, your motors are our lower inductance (2 mH) 960 oz-in motors, so there is a pretty big difference here.

Best regards,

Ahren
CNCRouterParts

[allengambrell]

At 50% jog I don't see the problem, so it probably is the speed. The latency seems fine and I am running mach.

I know I could just lower the velocity and accl, but what would be the right process to go about finding the top end and then back up say 10%. Would I start by turning up the acceleration or velocity?

I want to find a stable value to run at, but I want to know that value is not right no the edge. I can sit there and play with the values but it just seems like I am getting nowhere.

[Tool Designer]

Hello Allen. Try setting your micro stepping on the drives to no more than 1600. That should still give you about .001 per step. This is were I have mine. Under the motor tuning set your Steps per to:1018.59 , Velocity to: 800 , Acceleration to: 20 , Step Pulse to: 0 , and the Dir Pulse to : 0. If they still stall try reducing the Acceleration down a little at a time until they run consistently. After that if they still stall then reduce your Velocity down and try and bring the Acceleration back up. The X-axis has the most mass so work with that one first. The Y and Z will be faster. Like Ahren said, these motors have high inductance so you need to push them up to speed a little slower. These motors would work better with more voltage then 48vdc, but you can still run most applications with them. I'm thinking at a later date of going to a 72vdc power supply. Let us know how you make out. My best to you.

[ger21]

I think you're just another victim of buying a poorly matched Chinese stepper package.

At 48volts your only going to get about 40% of the speed that others get with motors less than half the size.

I know I could just lower the velocity and accl, but what would be the right process to go about finding the top end and then back up say 10%.

I don't think 10% is nearly enough of a safety margin.

I'd pick a conservative velocity, and a low accel of maybe 15, and jog around for several minutes, and also run some g-code for several minutes as well. If you don't get any stalling, increase velocity 10% and try again.

When you do see it stalling, back off velocity by 25%.

Then start increasing acceleration using the same method.

[allengambrell]

Do I need to turn down the microstep for the z axis. Right now I have it at 1600 that means it is 3200 steps per inch.

Also what are you doing for limit switches tooldesigner. I got the little machanical ones from ahren but they are so small I am not seeing a good way to mount them. I tought about ordering the optical ones like Euro3d they seem like they would be much eaiser to adjust. Also if I get them mounting how would be the best way to get them to be adjusted to square the gantry with x and a homing?

[allengambrell]

I tried out the settings from ToolDesigner and they worked much better. Here are the settings I ended up with. I am not sure if I need to turn down the microstepping on Z?

X 1018.59 799.8 55
Y 1018.59 1099.8 80
Z 3200 300 60
A same as X
All with pulse width and dir of 10

To Do:

I have yet to install 220v for the vfd. So have not tested that.

Also I am having problems with the water cooling system. I cannot get it to fill. The pump may be under powered for its location and the fact I used 3/8 tubeing instead of 1/4. Any ideas

[FannBlade]

Have any pics of the watercooling system?
Specs: Res,pump,rad etc.

[allengambrell]

Watercooling is a Themaltake BigWater 760 plus

[FannBlade]

You have to much head pressure for the pump.
If you can take pump housing out of PC and set it on something near level with the spindle,then let it run till all air is bleed out it may work once it's pumping ,bring it back down, the siphon effect may help it keep water running.
Then turn it off and see if it will start pumping again.

You may need to end up mounting it on the gantry to decrease head pressure and decrease line length.

[Tool Designer]

Allen, the machine is looking very good. Your good on the Z axis settings the way they are. I would not go any higher then 300 on the Velocity though. Keep us posted.

[Euro3D]

Hi Allen,

Check you don't have any kinks or pinches in your tubing, that will make it almost impossible to bleed.

The thermal take pump should bleed to coolant though you set up with ease. The pump I have from the aqua bay M5 set is rated for 1.8m of head.

Cheers

John

[FannBlade]

For feature reference this is what I would recommend using 1/2" ID lines then reduce near spindle. I think if your mount your unit at table height it will work,looks like you have around 20' of lines. Bay Reservoirs are by design generally located just above or even with CPU waterblock with less than 2' line.

Radiator
Reservoir
Pump
Optional Pump Top
Fans- 4 of these in push pull config

[cncrr]

Hey Allen,

Your machine is looking great! Btw where did you come up with the nice box for all your electronics that is mounted to the front of your machine. I like it.

Chuck

[allengambrell]

Got a enclosure for the vfd, still waiting on the 220.

I have to do some thinking about the water cooling. I just dont want to try it. I lost almost a full bottle of coolant last time. I am thinking about moving it to behind the y rail. Would I get too much dust here? Or would right at table height work better. I Am also thinking about changing the lines to 1/4, I dont think that would kill the flow.

The case is the electronics enclosure from a old photographic paper processor. I am a photographer and switched to inkjet so the old machine was just for scrap. Wish I could have found more parts like that instead of buying them.

[FannBlade]

As far as coolant just use distilled water and change it once a year. I think you will need to just try it, obviously closer the better. Nice job so far on the build.
I will be doing a CRP4848 this winter.

[kinghong1970]

For feature reference this is what I would recommend using 1/2" ID lines then reduce near spindle. I think if your mount your unit at table height it will work,looks like you have around 20' of lines. Bay Reservoirs are by design generally located just above or even with CPU waterblock with less than 2' line.

Radiator
Reservoir
Pump
Optional Pump Top
Fans- 4 of these in push pull config

+1
good recommendations here...
not sure how much cooling you need for a spindle but the items listed here are rated pretty highly among computer watercooling enthusiasts.

[kinghong1970]

Also I am having problems with the water cooling system. I cannot get it to fill. The pump may be under powered for its location and the fact I used 3/8 tubeing instead of 1/4. Any ideas

Allen,

TT system is a ok system but not really the best when it comes to watercooling systems.
you will find many computer wc'ing enthusiasts avoid a all in one package as such.

the TT radiaor is a high FPI model, meaning it'll clog up with dust bunnies pretty fast so a fan dust filter will do you some good...
the fan will also need to run at higher speed to get some cooling out of it.

now, with your system,
for priming and filling your loop, i would add a 8-10" T-line tube with a plug at the inlet of the system and fill T-line, run system, when coolant lvl goes down, fill again, and once filled, plug it with the correct sized plug and worm clamp. T line will also help bleed, a bit slowly tho.

for bleeding faster, you could try to lift and rotate the system and run the pump and make sure the reservoir is in the highest position...
but a decent sized reservoir will help bleed the system faster, the reservoir should be right before the pump.

the small reservoir that is attached to the TT system is very small and hence, making bleeding and filling a bit difficult.

[allengambrell]

Finnaly got my 220v 30a service installed for the x200 and spindle today.

I used the settings from the x200 thread and it seems to be working fine. But I was wondering if I could get the display to show the rpms instead of the frenquency. I am going to try modbus, but in the meantime I would love to see the speed instead of the freaquency.

Also I saw something in the settings for the number of poles. Does this have anything to do with the number of wires, my spindle has 3 plus ground. The only choices are 2 pole and 4 pole, I do not see a 3 pole?

Also I am running 220v to it, so do i need to set A082 to 220v?

Here are the settings I used in the x200

X200 settings:
A001: 00
A002: 02
A003: 400Hz
A004: 400Hz
A061 400
A062 200
A082: 230V
A151 200
A152 400
A153 0
A154 100
A155 00

B012: 10

H003: 2.2KW
H004: 2 poles