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Some questions about radius compensation
« on: September 19, 2008, 05:01:31 PM »
Im trying my luck at milling a 30mm diameter 15mm deep pocket and ran into some troubles using radius compensation.

This is my code

g0 z5
g41 D6
g0 x30 y47
g0 z1

g3 x30 y47 i0 j3 z-1 f300
g3 x30 y47 i0 j3 z-1
g3 x30 y42 i0 j3
g3 x30 y37 i0 j8
g3 x30 y35.1 i0 j13
g3 x30 y35.1 i0 j14.9

g3 x30 y35.1 i0 j14.9 z-2
g3 x30 y37 i0 j14.9
g3 x30 y42 i0 j13
g3 x30 y47 i0 j8
g3 x30 y47 i0 j3 z-2

g40


as you can see im using z moves while in g41 is this not allowed?

Offline ger21

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Re: Some questions about radius compensation
« Reply #1 on: September 20, 2008, 08:05:04 AM »
You should be able to do Z moves with comp on, but your code doe not appear to be correct. It seems like your I's and J's are not correct. Your calling for tool #6. What size is the tool?

« Last Edit: September 20, 2008, 08:43:33 AM by ger21 »
Gerry

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Offline ger21

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Re: Some questions about radius compensation
« Reply #2 on: September 20, 2008, 08:51:46 AM »
I would try getting that to run without comp before trying it with comp.

On a side note, I've been doing some comp testing for the last two hours, and some really weird stuff is going on. I have some comp code that used to work perfect, but now seems to run incorrectly at times, but changing the tool diameter, then changing it back will sometimes correct it, sometimes not. It will sometimes load correctly, and other times it won't. very strange.
Gerry

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Offline Graham Waterworth

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Re: Some questions about radius compensation
« Reply #3 on: September 21, 2008, 05:08:11 AM »
This is the simplest way to do circles with comp. :-

G21 G40
T6 M6
G00 G90 X30. Y47.
Z1.
G01 Z-1. F50.
G41 X45.  F100.
G03 I-15.
G00 G40 X30.

G01 Z-2. F50.
G41 X45. F100.
G03 I-15.
G00 G40 X30. Z1.
M5
M30

Graham.
Without engineers the world stops

Offline DAlgie

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Re: Some questions about radius compensation
« Reply #4 on: September 21, 2008, 11:22:02 AM »
Looks to me that you are using the wrong offset code, try G42, which puts the mill to the left side of the cut, for an internal pocket, You are using a G3, an anti clockwise cut, so that would have the mill outside the pocket
   DaveA.

Offline Graham Waterworth

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Re: Some questions about radius compensation
« Reply #5 on: September 21, 2008, 03:05:36 PM »
Hi Dave,

if you look at the code again I think you will see that KKamels code has no lead in to the diameter to be cut, to use G41 you have to move to the diameter to be cut to allow Mach to compensate.  If you check out my code that is what it is doing.

Regards

Graham.


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