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About LinkBackshope you do not disturb the neighbors with the rouer noises.
Joe
hope you do not disturb the neighbors with the rouer noises.
Joe
I got the 1/2-10 acme screw cut to lenght tonight (with a hand powered hack saw) after getting home from work, and assembled all the parts. Will clear the table and set up computer, PS, etc... Hope to run the Z stepper and check for any binding tomorrow night or before the weekend gets here. Just one step at a time, might as well get the bugs out of each axis as I build it.
Cheers
dewalt58
looks good Dewalt, keep it up
It LIVES!!! I fired up the Z-axis this morning....and it runs just fine. Took video of it running, sorry for the not so clear video, I gotta work on that, but posting it anyway:
http://video.google.com/videoplay?do...arch&plindex=3
With the 24VDC power supply, the max I can get is 39 IPM without it stalling, no amount of adjustment to Mach3 config motor tuning seems to change that, its the best it can do unless someone has a better idea. Ran it for almost an hour with no glitches. HobbyCNC Pro3 board, Keling 425oz stepper, Mach3 software. I'm very happy with it!!!
Cheers
dewalt58
Correction to last post....new Google video at:
http://video.google.com/videoplay?do...arch&plindex=3
Try this one....uploaded new video trying to get a better quality video, didn't seem to improve it much.
Cheers
dewalt58
DeWalt58,
39IPM seems slow. Of course my machine is not built yet, still waiting on my kit from Joe. I have my hobbyCNC kit built and have run the motors. Just moving air I have no problem running at an indicated speed of 250IPM. I have Mach configured for 1/2 8 2 start Acme as that is what I plan to use in the build. I set the hobbyCNC board for 1/4 steps and Mach for 3200 steps per inch. What settings are your using? How are your motors wired? Is your power supply the one in the hobbyCNC kit?
Hi Bob,
Cutting air at 250 IPM is not a true test, need a load on motor to know what she stalls at. I'm set for 1/4 steps, 8000 steps per inch ( I'm thinking yours is set wrong) in Mach3, 1/2-10 acme screw. Lets see, if 1 step is 1.8 degrees, then 1/4 of that is .45 degrees, 360 divided by .45 = 800 X 10TPI = 8000 steps per inch for my steup. At 8 TPI its 6400 steps per inch for yours. Unless your TPI is less on a 2 start acme? I think this is about it for this setup, weight (approx. 20 lbs) and friction is taking it toll on things, its a trade off, I want the weight for stability, and friction to take care of backlash. I will go with more voltage later on, the max the HobbyCNC Pro board can take, which is 42VDC. My power supply is a MeanWell switching unit, rated at 24VDC, 10 amps. I like regulated power supplys, power company lines vary alittle here. Oh yeah, almost forgot, to have Mach3 do the steps per inch for you when your machine is built, go to settings screen, and do axis calibration setup, it will ask you how far you want to move, then you tell it how far it did move, it will adjust the steps per inch automaticly!! Awsome software!! My motors are wired unipolor 6 wire. Mach3 settings are set in Config, motor tuning: Z Axis, steps per= 8000, Velocity=39, Acceleration= 1.4, step pulse=0, dir pulse=0. Thats a stable setting with the load on my motor without stalling. Changing the Acceleration won't change stall, just changes ramping up to speed. Hope this helps you.
Cheers
dewalt58
If you do this keep in mind that hand measurements will have significantly more error than the TPI rating of your lead screw. Unless you can measure at a resolution higher than the error rating of your leadscrew (.004in/ft on mine i believe). Obviously you would want to measure the largest line possible to reduce the error, even so i don't think you can get within an order of magnitude close to the lead screw accuracy.Oh yeah, almost forgot, to have Mach3 do the steps per inch for you when your machine is built, go to settings screen, and do axis calibration setup, it will ask you how far you want to move, then you tell it how far it did move, it will adjust the steps per inch automaticly!!
Yeppers Darkfred!! And even measuring the longest line won't account for varances along the threaded rod. Past work done has told me to cut junk wood first then measure the pocket hole and adjust for the size I want, if I wanted a perfect fit. It changes all over the place, you get what you pay for in a threaded rod. And mines an Enco cheapie!! Don't expect .0001 measurements from 1" to 6'. But hey! this is wood butchering we're talking about here, not aerospace machine work!!LOL
And BOB!! Your right at 3200 steps per inch!!! Acme 1/2-8 2 start is 4 threads per inch, had to look that up..dah....LOL I'll be interested in what you do get for IPM with that thing!!
Cheers
dewalt58
I guess speed is not a big deal on the Z axis anyway, except maybe for peck drilling. Maybe the voltage is the issue. I have no real experience yet, just what I have read on here.
But speed would be nice to get from one end of that long table to the other!!..
Cheers
dewalt58
One last bit. If you look at the spec on the Keling motors, they list 6V and 2A in unipolar (hobbyCNC board is unipolar). Look at the hobbyCNC 305ounce motors they have 2 versions. The 4.2V 3A version has a comment that says more speed over the 6V 2A version. The 2A version has nearly identical spec as the Keling and Joe told me the 305 would give 425ounce in bipolar mode so I think these motors are almost the same as Keling.
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