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Author Topic: Cuts much too large  (Read 5436 times)

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Offline Hood

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Re: Cuts much too large
« Reply #10 on: March 03, 2011, 01:12:40 PM »
It has the name of the profile you are using. If you start  Mach you will see at the lower right part of the main page the name of the profile.
Hood

Offline Pico

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Re: Cuts much too large
« Reply #11 on: March 03, 2011, 03:14:32 PM »
Here it is.

Offline Hood

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Re: Cuts much too large
« Reply #12 on: March 03, 2011, 04:06:41 PM »
Are your steps per unit set correctly? 2000 per inch doesnt seem like much.
Hood

Offline Pico

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Re: Cuts much too large
« Reply #13 on: March 03, 2011, 04:21:11 PM »
Don't know. I set this thing up over two years ago and don't remember what I set it at. I think I lost some settings in a computer problem and I've been having  difficulties ever since. What do you suggest? I'll run down and try 10,000 to see if it works better. I tried the automatic set several days ago and that cranked it up waaaay too much.

Offline Pico

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Re: Cuts much too large
« Reply #14 on: March 03, 2011, 04:34:13 PM »
10000 is too much. The motors whine and make funny noises.

Offline Hood

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Re: Cuts much too large
« Reply #15 on: March 03, 2011, 04:35:02 PM »
Well its easily calculated if you know a few things
Stepper or servo? If stepper it will normally be 200 steps per rev
Drive microstepping, for example Geckos will be 10
Any gearing between motors and screws
Pitch of screws

So as an example
200 steps per rev x 10 micro step = 2000 steps per motor rev
Screw 10TPI  and no gearing between motor and screw so it would need 10 turns for 1 inch so 2000 x 10 = 20000 steps per unit.
As said thats just an example, it will depend on your actual setup.
Hood

Offline Hood

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Re: Cuts much too large
« Reply #16 on: March 03, 2011, 04:35:55 PM »
10,000 may still not be too much, it may be your velocity and acceleration are too high. Work out the correct steps per unit via the method above.
Hood

Offline Pico

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Re: Cuts much too large
« Reply #17 on: March 03, 2011, 04:56:14 PM »
Thanks for the info, I'll dig into my instructions and see what I can find. Will report back.

Offline Hood

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Re: Cuts much too large
« Reply #18 on: March 03, 2011, 05:25:44 PM »
Ok.
Hood

Offline Pico

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Re: Cuts much too large
« Reply #19 on: March 03, 2011, 06:57:17 PM »
Motors are 200 steps/rev, set at 1/2 microsteps = 400steps per rev, with threaded rod at 20 TPI = 8000 steps per unit. I've set the motor tuning at that and the motors seems to work best with the accel and velocity at 5 to 10 %. Best of all, no more crazy cuts, I haven't measured down to the nearest hundred but the movement appears to be correct. Thanks for the help, this was driving me nutzo.