Lofted fillet between flat and angled shaft

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desweller
Posts: 18
Joined: Sat Mar 20, 2021 3:40 pm

Lofted fillet between flat and angled shaft

Post by desweller »

Hello all, greetings from not-so-sunny Gloucestershire, UK

I think this falls into a can't-see-the-right-way-to-do-it camp.

I am drawing a part for a 3D print. The design involves a shaft sticking out from a plate at a 45 degree angle. I want to fillet the transition between the shaft and the plate, but run the fillet all the way to the edge of the plate and also ensure that it's continuously tangential to both surfaces.

The fillet function gives a fixed radius, so I have been mucking around with the loft function instead. I thought the auxiliary path would be the solution (by constraining the two visible edges of the fillet), but it did not work the way I expected.

Is there a better way to achieve the transition feature I'm looking for? It's not critical by any means, but it it's possible I'd really like to learn what I'm doing wrong.

Image

Thanks in advance for your advice!

Des Weller

EDIT: for some reason the image won''t display, here is a link

OS: Windows 7 Version 6.1 (Build 7601: SP 1)
Word size of FreeCAD: 64-bit
Version: 0.20.26155 (Git)
Build type: Release
Branch: master
Hash: 0926a4148bcff11249fd4f56bc30256102ffe105
Python version: 3.8.6+
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drmacro
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Posts: 8869
Joined: Sun Mar 02, 2014 4:35 pm

Re: Lofted fillet between flat and angled shaft

Post by drmacro »

Can you post your file?

I'm thinking this will be a good use for Curves workbench and maybe Surfaces workbench.

(general note: the first thing I'll do is delete the Std_Part object Image
It's not needed for a single solid and is actually redundant. ;) )
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
desweller
Posts: 18
Joined: Sat Mar 20, 2021 3:40 pm

Re: Lofted fillet between flat and angled shaft

Post by desweller »

Thanks, with a bit of luck my file is attached.
Attachments
2021-11-27 Variable radius fillet.FCStd
(335.71 KiB) Downloaded 25 times
desweller
Posts: 18
Joined: Sat Mar 20, 2021 3:40 pm

Re: Lofted fillet between flat and angled shaft

Post by desweller »

Oops, saved it with one of the wonky lofts. Lemme try again.
Attachments
2021-11-27 Variable radius fillet.FCStd
(43.62 KiB) Downloaded 21 times
chrisb
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Re: Lofted fillet between flat and angled shaft

Post by chrisb »

BTW: You can edit your existing posts and replace attached files.
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drmacro
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Posts: 8869
Joined: Sun Mar 02, 2014 4:35 pm

Re: Lofted fillet between flat and angled shaft

Post by drmacro »

I used Surface workbench to fill surfaces between your curves.

ATM it doesn't create good surfaces because the surface droops below the planer surface (shown in red below)...That could be changed with Blend curves in the Curves workbench.

And the bad surfs don't produce a valid solid in the attached file. But, this gives an idea.
varfillsurf.png
varfillsurf.png (120.78 KiB) Viewed 869 times
Attachments
2021-11-27 Variable radius fillet-mac.FCStd
(83.18 KiB) Downloaded 21 times
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
desweller
Posts: 18
Joined: Sat Mar 20, 2021 3:40 pm

Re: Lofted fillet between flat and angled shaft

Post by desweller »

Thanks Doc. That looks gert lush as we say round here. I'll take a look!
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