Tool Offsets - What's wrong with this Gear?

[edo]

I took a gear drawing from AutoCAD and used KCAM to convert to G-Code. The first cut looked good, but the teeth were pretty small - I forgot to account for the tool offset. I added G41 D1 and set up Tool 1 in Mach3 as the 1/8" bit that I'm using.

The tops of the teeth came out correctly, but there's a strange undercut in the corners at the bottom of the teeth and there's a peak where it should be flat between these corners. In the picture, the gear in the back is the first one I cut with no offset and the one in the front was what I got when used G41. You can see the space at the base of the teeth and the little spline in the middle.

[HuFlungDung]

What is wrong? It's undercut

I suspect it is a case of tool interference due to inproper offset of the path within the controller's rad comp routine.

The best way I've found to fix a troublesome path for radius comp is to fillet the internal corners of the 2d curve to match the tool radius. If the controller could execute the original path correctly, this is exactly what you will get anyways.

So where the tooth meets the root circle, fillet the geometry to your 1/16" radius. You might discover that you will have to do some manual trimming to get a good continuous curve.

Then, redo the toolpath on this new geometry.

[edo]

Thanks, Hu. I'll play with it some more and see what I can do with it. I'm new to all this and was foolish to think it would be as simple as putting a G41 in the code.