mgandy02
Fri 23 October 2009, 06:16
Let me first introduce my build. My MM is part something else and the x rails throught the z-slide is true MM. I first started my CNC experience building a table for a plasma cutter but quickly figured out I would get more use from a router.
So the table is built from 1.5" x 1/8" wall square tubing. Two hundred feet to be exact. Then I built the gantry from MDF and used some THK linear rails that were about to be junked at work. To make a long story shorter I stumbled onto the MM site after I had been frustrated that my new creation was not accurate enough.
So began the rebuild. I opted to keep the original table and just add the mm components. I got the parts from Joe in alabama and the v rollers from SuperiorBearing.
I originally ordered 4 203Vs from Gecko and they recommended Keling to purchase my motors and PS. So I ordered a KL-7220 power supply, 2 KL34H2120-42-8A, and 2 KL34H295-43-8A. I got the belt reducer idea from Chopper and made a couple of adjustments so I have 4:1 reduction on all of the axis driving a 40 tooth pinion.
After getting all of the wiring done and mach3 setup I tried my new toy. Doing a simple 0.5" jog at 10 ipm all axis are +/- 0.002". I thought that was pretty good. Time for a test cut. I made a sample cut out of a 4" square. I cut it at 20 ipm and everything came out perfect. It made 4 passes at 1/4" deep. Perfect.
Then came the real test. I have a flag the I had created on VectorArt3d website. Created the g-code in artcam and exported using the mach3 post processor. I tried cutting it at 100 ipm and it came oute terrible. Every time it started a new slice the Y axis didn't return to the true starting point. It was actually too far positive. So it was making offset stairs. When it was over the y axis zero was actually about 1.25 inches greater. I have the motors wired ( 2120 = Bipolar parallel ) and ( 295 = Bipolar series ).
So i guess I am asking is 72 volts too much? Should the motors be wired different even though they are precise at a low speed? I attached several screenshots from how i have mach setup. Thanks in advance for any help.
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So the table is built from 1.5" x 1/8" wall square tubing. Two hundred feet to be exact. Then I built the gantry from MDF and used some THK linear rails that were about to be junked at work. To make a long story shorter I stumbled onto the MM site after I had been frustrated that my new creation was not accurate enough.
So began the rebuild. I opted to keep the original table and just add the mm components. I got the parts from Joe in alabama and the v rollers from SuperiorBearing.
I originally ordered 4 203Vs from Gecko and they recommended Keling to purchase my motors and PS. So I ordered a KL-7220 power supply, 2 KL34H2120-42-8A, and 2 KL34H295-43-8A. I got the belt reducer idea from Chopper and made a couple of adjustments so I have 4:1 reduction on all of the axis driving a 40 tooth pinion.
After getting all of the wiring done and mach3 setup I tried my new toy. Doing a simple 0.5" jog at 10 ipm all axis are +/- 0.002". I thought that was pretty good. Time for a test cut. I made a sample cut out of a 4" square. I cut it at 20 ipm and everything came out perfect. It made 4 passes at 1/4" deep. Perfect.
Then came the real test. I have a flag the I had created on VectorArt3d website. Created the g-code in artcam and exported using the mach3 post processor. I tried cutting it at 100 ipm and it came oute terrible. Every time it started a new slice the Y axis didn't return to the true starting point. It was actually too far positive. So it was making offset stairs. When it was over the y axis zero was actually about 1.25 inches greater. I have the motors wired ( 2120 = Bipolar parallel ) and ( 295 = Bipolar series ).
So i guess I am asking is 72 volts too much? Should the motors be wired different even though they are precise at a low speed? I attached several screenshots from how i have mach setup. Thanks in advance for any help.
6776
6777
6778
6779