Help With Fillet

In the attached file I have a shaft outlet. I need to round the edge to create bossing for the outlet.

The radius must be zero at the end (left) It should be about at 16" radius about 6 ft in. Then expanding to about 65" at the end (right).

Whenever I try to fuse edgefillet I get odd results (even with a much smaller than desired radius). Apparently the transition from the flat area at the top and bottom cause problems.

Problem Fillet.3dm (3.6 MB)

How might accomplish this task?

hi Jim, its not fully understandable where you want the fillet, i use metrics and its a little of a fiddle to follow your exact wish of dimension and i am a bit lazy today, maybe indicate it with points and describe it in the file or use the file i reworked and see if it works for you now.

if you explode the surfaces and hide the propeller shaft surface however its called then you have split edges you can also see that here on my image not so well if you use the command show edges then little black dots appear. run MergeAllEdges on this.

after that i dupped the edges shown below joined them and used fitcrv with the same degree and a tight tolerance to create 2 single cuves to loft a single surface. see if that helps, you still have a mess in the surfaces, i know you work with numbers from a table or something but i again advice you to try understanding what the surface is for and trying to recreate them as simple as possible. attached the file see if it works now better.

edit: some random testfillet with 0 on the front as you wanted worked now, some rest peaces where created which where not needed it joined automatically to a polysurface so i guess it should work from here on.

Problem Fillet.3dm (3.5 MB)

Thanks, I am trying to work through this. The big problem here is the half moon shape at the back that makes things very difficult. It’s a giant compromise here (as it must have been with the original).

The file attached appears to be my original.

nope, i tried now, it should be a red surface and when you explode it you see that the shaft outlet is rebuild to one surface and has the 2 curves above it for the loft, try if it fillets now. i didnt amend the random fillet if thats what you were looking for since it was not accurate according to your wishes anyway.

OK, my misteak.

your steak exactly :smiley: did it work out?

I am still trying to corect the erors to get the modle to work.

Hi Jim - FilletSrf is what I’d use here, followed by some trimming & joining -

The surfaces, to my eye, are overly dense though - I’d shoot for simpler surfaces with cleaner curvature.


I seem to get very dense surfaces here that result from matching the edges of adjacent surfaces. For other areas get natural matches. The problem here is that moon shape thing.