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Chamfer milling in gibbscam 2014: having a constant depth for deburring an edge at an angle?


Feb 5, 2008
I am trying to deburr a spanner nut slot, and was wondering if gibbscam can do what I want.

So the spanner nut has one side with a 50* chamfer, that I would like to deburr. The slot is only about .090 deep and 1/4" wide.

I have a chamfer mill here that is 60 degrees included, comes to a pretty sharp point. I would like to chamfer the edge shown in the picture below, but would like the code to move the tool in X/Y to achieve the chamfer, while leaving the depth of the tool at about .090"

No matter what I've tried so far, I can't get it to do anything except try to walk up the edge in z as well.

Is this possible with gibbs (2014)?


Edit to add what I think it would look like from above:

You have to redefine your edge to be a constant Z as in your second picture. In other words, project the edge down to Z0 by the angle of the chamfer mill, then choose that line to follow.
You have to redefine your edge to be a constant Z as in your second picture. In other words, project the edge down to Z0 by the angle of the chamfer mill, then choose that line to follow.

Thank you for the tip.

So I wasn't 100% sure how to go about what you wrote, but I did in the following way with okay results. I am wondering if there was a more proper way to do what you say and project the edge at an angle.

I rotated the edge profile in the XZ plane by 30 degrees. I think it should have been a little more than 30 degrees based on the result, though.

Then i switched back to the XY plane and did a force depth of that profile to the bottom of the slot.

This is the result of that:



I think it looks pretty good, might tweak either the geometry or the code to get it to go a little further down but this is very much the intended toolpath.

Is there an easier way to do it? Was a bit cumbersome but not impossible.
As far as I know you cant, and even with trying to trick it with modeling in Solidworks and creating a loft for the tool to just follow it still doesn't work correctly.
I did get it extremely close, but was trying to get the math exact, because your trying to start at a 0 width chamfer and quickly go to some width of chamfer, but the angle changes constantly, because you have 60°
cutter x angled surface, So trying to get it to math out and keep a constant width of chamfer with varying slope from constant 60° degree cutter, I can t get it exact.
thanks for putting this crap in my head, been working on it for an hour. :D
I haven't tried, I gave up but, it would need the chamfer modeled in first, you cant follow a sharp edge and have it work, that is to create the correct follow path anyway.

edit: ok, I finally got it exact with the math/geometry, but it doesn't look any better than what you have in your image. So even getting it correct it doesn't look good.

Oh wait, I missed something, to be continued....
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I did actually get it to work, but you do have to model it correctly for it to work.
using standard fillets in Solidworks even when your loft cut is set to the correct vector angle, it doesn't actually modify the angled surfaces correctly,
but the draft modifier does.
Then extending the sheet into the face tangent and trimming it or similar functions will create the correct path to follow.
then in Gibbs just use a contour pass.
Thanks guys.

So what I did was within gibbscam, not a solid program (i have access to nx if i really need to). gibbscam doesn't SEEM to have any sort of ability to do it "automatically" but again, once magno_grail suggested how to do it, i did get it done. And the geometry wasn't perfect because the 50* angle on the front would have a different point/angle of tangency to the conical shape of the tool.

I moved the point up .010" in gibbscam and it looks damn perfect, and the actual result looks perfect too.

I'm slotting 6 of these spanner nuts all together on an arbor in the mill (since the live-tool lathe we usually run these on was down for repair, and we need to push them through). 300 parts total, and this is much better than manually deburring them. (hard 4140)

I only modeled one part in gibbscam, but copied the profile and strung them together to run all 6 parts. I actually want a bigger chamfer on the angle than at the top of the diameter, so how it looks is perfect.


I just wondered if it was possible to get it exact, so mission accomplished. :D