Tough Inside Fillet

Fillets seem to be the bane of my existence. All I want to do is fillet this edge.

The other edges were filleted a while ago, and now that I BooleanUnion-ed the top and bottom together, I’d like to round off that edge. When I try a FilletEdge, all I get is a surface that extends past the object on both sides. What is the secret sauce here? Thanks!

3DR_Telemetry_Case_2.3dm (3.3 MB)

Will this work for you ?

3DR_Telemetry_Case_2_fillet_fix.3dm (908.0 KB)

I only included the part you wanted filleted, not the whole thing.

You can use fillet edge and just trim it all up. Or use filletsrf and trim it up. I used filletsrf.

It looks right. Can you tell me the steps to take? Thanks!

As you already mentioned with filletedge it left you with the extended surface. Extend the other two fillets that will intersect that surface. Trim the fillet surfaces. That will make all the fillets intersect where you want. Then trim up the surrounding planar surfaces using the surfaces from the fillets. Join all together using the Join command when finished.

thanks but i’m still a bit lost. so i need to extend the filled surfaces that are adjacent to that fillet? do that with Scale1D?

Hi David.

After you attempted the FilletEdge command you were left with an unjoined, extended surface. What you could then do is use the explode command to break up the polysurface into individual surfaces. You then use the Extend Surface command to extend the adjacent fillet surfaces until they intersect with your new fillet surface that was created by your FilletEdge attempt. Then use the Trim command to trim up all three fillet surfaces. You then use the Trim command again with the filleted surfaces to trim up the planar surfaces. After all trimming is completed join the surfaces back up using the Join command.

I may be missing steps there. I’m not the best communicator

Here is a video that might help. I created a similar scenario, created a fillet that that was extended but not joined.

There are a couple steps I could have done a little better but this shows roughly what I mean.

I just realized your using mac version. I use Windows. Not sure if there is any differences with the commands I used.

wow. thanks for the video. i solved it by lowering my radius, which in turn allowed corners to me built. however, i learned more about how Trim works, and thats huge. thanks!