Chamfer square hole
Chamfer square hole
(OP)
The problem I'm about to describe sounds like it should be easy to resolve, but has me dumbfounded.
I have a rectangular hole in a plate with a radius (not full) forming one side of the rectangular hole. There is a .025 chamfer on three edges of the hole. The intersecting chamfers have a .040 radius, and the two ends of the chamfer also have a .040 radius. When you chamfer the edges, you get a sharp corner where the chamfers intersect. This of course, does not reflect what actually occurs when you use a conical form tool to machine the chamfers. Additionally, when you chamfer the edge intersecting the unchamfered edge, you get a sharp end to the chamfer, whereas in reality you obtain a conical surface at the end of the chamfer.
I've tried doing a cut-sweep which does fine on the right angle edges to be chamfered, but leaves a vestigial post or boss at the center of the .040 R at the end of the chamfer. The sweep cut command fails if I enlarge the profile to try to eliminate the post because the sweep profile interferes with itself.
Is a sweep cut the best way to do this?
Is it possible to create a 'form tool' with a 90 degree tip and conical ends? This form tool could then cut this shape out of the part.
Does anyone have a better idea?
Thanks in advance,
Chris Marinelli
Dynatech Engineering
I have a rectangular hole in a plate with a radius (not full) forming one side of the rectangular hole. There is a .025 chamfer on three edges of the hole. The intersecting chamfers have a .040 radius, and the two ends of the chamfer also have a .040 radius. When you chamfer the edges, you get a sharp corner where the chamfers intersect. This of course, does not reflect what actually occurs when you use a conical form tool to machine the chamfers. Additionally, when you chamfer the edge intersecting the unchamfered edge, you get a sharp end to the chamfer, whereas in reality you obtain a conical surface at the end of the chamfer.
I've tried doing a cut-sweep which does fine on the right angle edges to be chamfered, but leaves a vestigial post or boss at the center of the .040 R at the end of the chamfer. The sweep cut command fails if I enlarge the profile to try to eliminate the post because the sweep profile interferes with itself.
Is a sweep cut the best way to do this?
Is it possible to create a 'form tool' with a 90 degree tip and conical ends? This form tool could then cut this shape out of the part.
Does anyone have a better idea?
Thanks in advance,
Chris Marinelli
Dynatech Engineering





RE: Chamfer square hole
Chris
RE: Chamfer square hole
RE: Chamfer square hole
RE: Chamfer square hole
The edge break is for clearance on a turbine engine variable vane trunnion. We are reverse engineering the part, so we must duplicate what is present. I know it's an odd example, but I think the general idea of removing material with a solid moving along a path is something many would want or need.
RE: Chamfer square hole
(electrical discharge machining)
Flores
RE: Chamfer square hole
In SolidWorks (or whateverCAD), when it won't giving me the chamfer I expect, I break the chamfer into sepatate "Cut" features. So for your model, I would Cut-Sweep along the *straight* edge, then to a Cut-Revolve (separate feature) in the corners.
Ken
RE: Chamfer square hole