Fast and easy way to delete fillets to cornered

Rhinoquestion.3dm (3.0 MB)
in drawing in orange a original file with a lot of fillets.
in gray, how i want it and the green one the (for me impossible)file im working on to make it like the gray ones.
It is a cushion set on a enginebox from a chaser rib boat.

Hello there, I am looking for an easy-er way to delete all fillets and put it back in the original shape (without it) before. It is a .stepfile probably made in solidworks or inventor… so i dont have any history of it. Normally with less difficult shapes i would explode,shrink and extend all surfaces. extend them seperatly more and create solid. and sometimes i need to extend trim or draw some extra curves to get back to the shape i want. but with this particurly shape. i get lost when i use the expertise i know for so far.:stuck_out_tongue:
Greets Alex

this is a bit tricky, and there is not really a fast way to do this in Rhino. Attached is using ExtendSrf on the exploded shape in combination with ConnectSrf (and some trimming)

unfillet.3dm (208.2 KB)

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This is the first problem you need to address.
If you open a Solidworks file in Rhino you should expect that the tolerance setting will be ridiculously tight. Rhino5 was the last version of Rhino that did not have this bug. Its best to always import a Step file from Solidworks raqther than opening it. If you do use Open command then you need to next go into Options and set the model tolerance to something reasonable. For the size of your model I would use a tolerance of .005mm.

This is not a very complex shape. There really are only 9 surfaces that you need to extract, shrink, untrim and then extend. The part is symmetric so you only need to do one side and then use Mirror.

This file: Rhinoquestionx.3dm (2.3 MB) shows how I would do it using the Filsrf_Join script that I posted last week.

The surfaces that will be filleted are organized in to 4 sets that will be joined by fillets. In the file the sets are pink, green, cyan and purple and that is the order the fillet strings should be made. The order is important so that the convex fillets can properly wrap around the concave fillets.

So first the pink and green are used and that results in a pink polysurface (the result inherits the properties of the first pick). Then make the fillets between cyan and pink which results in a cyan polysurface. Then cyan and purple which again makes a cyan result. Then Mirror can be used to make the other half.

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thnx for the respons and sorry for my late reaction. Had some days off.
Could you save the file in rhino 7? because i can’t open rhino 8.
Thnx again

Hi Alex -

There’s a stand-alone 3dm file version converter available from this thread:


Thank you, that will do indeed.