topic Re: Glitching when chamfering/fileting coils in Fusion Support Forum

Glitching when chamfering/fileting coils

Anonymous — Thu, 07 Jan 2021 21:13:35 GMT

Hi,

I have noticed fairly inconsistent performance when chamfering and filleting coils.

What am I trying to do: I tend to create a lot of parts that interface with threaded existing parts. Many of these existing parts have non standard thread so I have to reverse engineer what is there and model it in Fusion 360. The parts I create are fed to my 3D printer so I do need the threads modeled, not just represented.

Workflow: After taking my measurements from the physical part I create a surface at either the minimum or maximum dimension then create a coil on that surface. I exclusively use the triangle profile. Then once the coil is created I like to fillet the peaks and valleys of the thread to help manufacture. (For the uninitiated, creating fine threads with a FDM printer is asking it to do something it is not great at so concessions need to be made on sharpness.)

The Problem: When I create these fillets or chamfers I notice glitching in the generated profile when viewing in a sectional analysis. The attached pictures happen to be the latest occurrence, prior occurrences are nearly identical in form. Interestingly these glitches are not uniform although the coil profile is. I have tried altering settings in the chamfer/fillet operation but that seems to move the glitching, not eliminate it.

Re: Glitching when chamfering/fileting coils

g-andresen — Thu, 07 Jan 2021 21:59:38 GMT

Hi,

Without analyzing the file, a statement is not possible.

Therefore
Share the file:
File > Export > save as f 3d locally > as attachment to next post

günther

Re: Glitching when chamfering/fileting coils

Anonymous — Fri, 08 Jan 2021 05:51:59 GMT

Hi Guenther,

I don't wish to share my work with the world yet so I created an example object to illustrate the bug. It is just a coil with a reasonable filet applied to the tip of the profile. Hopefully this is sufficient.

Re: Glitching when chamfering/fileting coils

HughesTooling — Fri, 08 Jan 2021 13:25:51 GMT

This looks like just a display problem. If you change the display detail control to high it looks OK.

Analyse still looks bad but the quality of section analyse has never been that good. If you actually split the body and inspect it's good. File's attached.

Mark

Re: Glitching when chamfering/fileting coils

HughesTooling — Fri, 08 Jan 2021 13:30:28 GMT

Just one more test that shows the actual geometry is correct is create a sketch and use project intersect.

You can see the intersection curve is accurate.

Mark

Re: Glitching when chamfering/fileting coils

Anonymous — Mon, 11 Jan 2021 02:57:20 GMT

I appreciate the help, and the double checking techniques. More tools in my tool box to deal with the sometimes weird behavior of this software.