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Author Topic: cuts are off a bit  (Read 12807 times)

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Offline Hood

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Re: cuts are off a bit
« Reply #10 on: January 31, 2008, 07:22:57 AM »
Sorry for not getting back, been busy . To answer your earlier question, its the lots of small moves thats causing your jerky movement.
 Your new code is better for the circle but the outside is a bit screwed its jumping around and cutting bit by bit instead of a continuous chain. I have not really used LazyCAM much so cant advise but I am sure there must be a way to chain them correctly. I am sure you will get it with a bit more messing in LazyCAM.

Hood
Re: cuts are off a bit
« Reply #11 on: January 31, 2008, 11:28:59 AM »
Yeah, that's what I meant by whacked out. That is my first time using LazyCAM for anything but entertainment or frustion. Everything else I posted from it was a garbled mess.

Thanks for the help. Could my original issue be backlash? I don't have an accurate way to measure it right now, but it did run past my mind.



Edit: ... Wow. That was easy. I spent a while trying to re-organize entities, and after that didn't work I clicked "clean. This little button just put everything in order for me. New G-Code is added.
« Last Edit: January 31, 2008, 11:40:43 AM by cxixer »

Offline Hood

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Re: cuts are off a bit
« Reply #12 on: January 31, 2008, 04:19:29 PM »
Code looks more like it now :0
If its backlash then you could measure it no problem as it would be a load for 1/16 out.
Hood
Re: cuts are off a bit
« Reply #13 on: January 31, 2008, 07:29:45 PM »
For that much, there would be some noticable play I would think. And I have never noticed any when assembling or adjusting the machine. It's pretty tight.

Offline Hood

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Re: cuts are off a bit
« Reply #14 on: February 01, 2008, 03:00:12 AM »
Have you run with your new code? If so did it still come out wrong? Can you give me the dimensions your part is meant to be at the max/min of each axis and also what the circle Dia is supposed to be, also what it actually comes out as.
Hood
Re: cuts are off a bit
« Reply #15 on: February 01, 2008, 11:21:41 PM »
OK, so I noticed something today. When I had a shop machine the pinion shafts for me to fit on the motors, they didn't do a perfect job. There was some play in the shafts where they connected to the motor, which caused some serious backlash after they worked themselves loose. I modified the x and y axis a bit and added a spring compensation to the x axis because the play was worse. But there appears to be no backlash, or at least not any play in the gears anymore.

So I went ahead and cut the mount with the code generated from lazycam. It cut exactly what it was supposed to (according to my tape measure, that is). The problem is, the circle cutout is 1/4" too big, and the outside dimensions are 1/4" too small.

I can not offset in lazycam to account for the bit because I did not get a license for it yet, but it appears the cuts being off just a bit and the circle issue is figured out.

Offline Hood

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Re: cuts are off a bit
« Reply #16 on: February 02, 2008, 03:16:52 AM »
Well I am not sure about LazyCAM and offsets but if thats all thats wrong now you could easily redo your drawing with the circle a 1/4" smaller and the outside 1/4" bigger then it should come out right.
Hood
Re: cuts are off a bit
« Reply #17 on: February 02, 2008, 03:19:27 AM »
Yep, I thought of that. And I think I can deal with doing that for now until I can get a cam program, or until I decide to get a license for lazycam if I end up liking it enough. I'm pretty happy with the results I've had with my homemade cnc though, and recommend it to anyone!