Round corners

[slawsonb]

I am doing an outside offset contour on part with 90 degree corners. The problem is that the corners are being rounded off instead of being sharp as the drawing defines. Is there a setting I am missing somewhere?

Bruce

[HuFlungDung]

Are you sure? An offset path around a square will have rounded corners because the tool swings around the corner point in an arc.

If your machine rounds the corners off, it may be some kind of motor tuning issue, meaning the motors are not responding 'tight enough' to follow the contour commands.

[Geof]

What kind of machine? How round are the corners? If you are dealing with a commercial CNC some do have a Setting that can affect corner rounding.

[slawsonb]

Actually it looks like sheetcam is displaying the correct tool path but when exported to mach 3 the corners get rounded off. I have not completed my CNC mill so no real results yet.

Bruce

[ger21]

Mach3's screen display is not necessarily the actual cut path. The screen isn't updated constantly and at higher feedrates you may see rounding in the display, when there isn't any in the actual toolpath. Post the g-code here and we'll take a look.

[ger21]

My previous posts assumed the rounding was during a cutting simulation. Is this correct?

[slawsonb]

Originally Posted by ger21 My previous posts assumed the rounding was during a cutting simulation. Is this correct?

Correct.

[Konrad]

Your offset will make a arc around a square corner....but the part should remain square.
Konrad

[ynneb]

I know your problem, You need to use the exact stop setting in Mach. This is not a sheetcam issue.

[slawsonb]

Here's the G code.

[slawsonb]

Originally Posted by ynneb I know your problem, You need to use the exact stop setting in Mach.

How do I do this?

Bruce

[ynneb]

In mach select at the top /config/state and see this picture.

This mode is good for doing hard angles, bit painfully slow when cutting curves.