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Hello , I am new to the forum, but I've been reading it for a while. I have a friend that has access to a big CNC and he will make me some parts free.
I am about to order a 4-axis controller and four 305oz-in steppers (hobbycnc.com) with a 32Volt unregulated power supply.
Then from "harbor freight" Sieg X2 mini-mill and a 4inch rotary table.
My plan is/was/maybe ; just mount the steppers to the handles and go.
When I strip a gear then I will do the Belt Drive upgrade.
It is going to be used for PCBs with fine traces, Art, engraving, small parts, and very small parts.
What is the backlash like out-of-box? Am I going to have to add Ball-screws?
I have seen here where they have added Ball-screws to the Z-axis, but did they do the same with X and Y axis?
Is the Backlash visible?
Do I need to do a Water-Cooling system for the X2 motor?
Do I need Heat-Sinks for the Stepper motors?
I only have about $500 for a Mill; Do you have any recommendations?
you can save a lot of board building by getting the 3 keling 4030 microstep
drives with breakout board and 5 volt power supply for the logic biding starts at $100 you will get more power from the steppers in bipolor if you want 4 axis you just
have to buy 1 more from keling they are $54.95 each here is the ebay
listing http://cgi.ebay.com/ws/eBayISAPI.dll...PageName=STRK:
If you're just getting into this, it might be a good idea to read up on X2 conversions before jumping at anything. If you do a search here and with Google, you'll find a lot of information on X2 conversions. This ought to go a long way toward keeping you from reinventing the wheel. Good luck!
I am just getting into this, It will be my first CNC.
I have read that there is a mm in backlash.
Could you point me to a good X2 conversion Kit? that I can trust ordering from. With this much money I don't trust Ebay.
http://littlemachineshop.com
And I may just do the "Air Spring Conversion Kit" too just to save on shipping.
I haven't done an X2 and don't claim any direct knowledge but many here seem to have used kits from:
http://www.cncfusion.com/minimill1.html
Of course, this is for the mechanical parts. For the electrical control system, Gecko seems to be the gold standard for drivers.
Thanks for the info.
I am going to thank it over; Really want a 4+axis CNC. It is still do-able.
$1300 for the X2 mill with rotary table, gas springs, and conversion kit
$ 110 for a 34Volt 10Amp Power supply
$ 382 For the Controller and four 305oz-in Steppers
$1800 total for a x9" y4" z8" travel
OR build one from scratch ( x40" y40" z36" travel and maybe a 5th axis later-on)
$980 for THREE 0.375 In Dia,48 In Long ,Steel, Ball Screws And nuts unpacked
$1500 for "T-slotted Structural Framing"
$500 for bearings
$500 for a drill
$ 110 for a 34Volt 10Amp Power supply
$ 382 For the 4axis Controller and four 305oz-in Steppers
$ 100 for 4" rotary table
about $4100 total
I'm looking for the same type of info. I'm getting the itch to convert one.
http://www.hossmachine.info - Gosh, you've... really got some nice toys here. - Roy Batty -- http://www.g0704.com - http://www.bf20.com - http://www.g0602.com
if you want to save money i am selling 3 new never used keling 4030 microstep
drivers for under the cost of new they come with breakout board and 5 volt
powersupply for logic each one of the 4030s is $54.95 each the rserve on this listing is less than 3 x $54.95 biding starts at $10 everything is new in this listing never used
http://cgi.ebay.com/ws/eBayISAPI.dll...PageName=STRK:
I have an X2 and will offer the following:
If you can possibly get an X3 over an X2 I would do so, even if it means waiting a bit longer. I have the X2 and my friends have a X3, the X3 is a much, much nicer machine. I wanted an X3 but when I bought they were not available for many months so went with the X2.
If you are set on a X2 you will need to do something with the screws as out of the box, backlash is way to much to do the types of things you listed. You can likely rework the nut to get something that will get you started in the near term. If you look at installing new screws plan carefully as there is not much room unless you start hogging out the castings. Getting the gibbs and overall machine adjusted will take some time as the X2 is basically an assembled kit.
For drives my vote is for Gecko. For motors I used those from AutomationDirect.com
We have a 3 axis kit for x2 machineOriginally Posted by heilcnc
here is the link
http://www.kelinginc.net/CNCNEMA23Package.html
"I am about to order a 4-axis controller and four 305oz-in steppers (hobbycnc.com) with a 32Volt unregulated power supply."
I would not recommend this kit (unless you do the mod below)....I have the hobby cnc pro and it finally works correctly after I had to modify the circuit to let Mach 3 control the motor current.
Thank You Gary!!
Current Reduction, HobbyCNC - Mach3
"The problem:
So, why is the HCNCP's timer set for ten seconds? I suspect the reason for that is because the timer-sync function has been bundled with the current reduction function. Remember, the timers for each axis are independent, so, if there is no activity on one axis, it could go to reduced current while another axis is in motion. Due to a total lack of experience in such matters, I can't say for certain, but it seems to me that you would always want all axes at full current while any are in motion. And, I believe this is the reason for the '10-second' timer on the HCNCP: If any one axis is idle for ten seconds, it's likely that all cutting and motion has ceased, and it is OK to reduce the current.
That's probably a pretty good assumption, so why is it a problem? Well, the issue is, that it is the step pulse that triggers the timer, turning off the sync and restoring full current. That step pulse also goes directly to the driver chip, which immediately starts the commanded step, and that action doesn't wait for the timer/sync/current functions to return to a normal operating state.
So, what happens is, you have an axis that functions normally most of the time, but when it has been idle for ten seconds, it stalls when attempting to begin motion again. This apparently happens because the current ruduction or sync functions have not really turned off when the step action starts. The common suggestion is to "reduce the acceleration" or "reduce the step rate", which is an attempt to slow down the initial motion to allow the circuit to 'catch up'. Apparently this is inadequate in some situations, or the driver software doesn't support it; regardless, it's what's technically known as a 'kludge'.
The difficulty in diagnosing this problem is that it manifests itself differently on different systems; and all systems are different: Different motors, screws, nuts, lubrication, cables, masses, voltages, currents, etc. Some will never see an issue, while for others it appears to be a persistent problem. In testing on my own system, it's pretty easy to set up a step rate and acceleration that will jog reliably when there are no delays between jogs, but which will nearly always stall when attempting to jog after a 10 second idle time. This can be nearly always fixed by reducing the acceleration, or, by disabling the current reduction (placing J4). Since the problem is fixed by disabling the current reduction, we can be pretty sure that sync is not a part of the stalling problem (disabling current reduction does not affect the sync function). The question is though, why, should I have to live with reduced acceleration all of the time to accomodate this single problem case, or, why should I have to forego the temperature reduction advantage of a reduced current control to get back that acceleration?"
Current Reduction, HobbyCNC - Mach3
Hope this helps,
Robert
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