Ideas for rounding corners on odd shapes?

So my kid has lost a bunch of these shapes and I'm going to make a replacement set.

Does anyone have any ideas for how to get a consistent roundover on the corners? I have a router table but no CNC.

The square and rectangle I could do with a roundover bit and the blocks on their sides. But I don't see any obvious solutions for the pentagon and triangle.

I'm totally fine just hand sanding these, but this kind of problem solving makes woodworking fun!

12 points · 8 comments · view on lemmy.world

8 Comments

DavidP@toast.ooo · 7 pts · 3y (1 reply)

An idea that came to mind.. I do have a 3D printer so I could make 120° and 72° round radius guides like these.

frmz@sh.itjust.works · 8 pts · 3y

If you didn't have a 3D printer, you could still print a template on paper, glue that to a board, saw/rasp/file/sand to the line and then use the shaped board as a template. Double sided tape should probably be good enough to keep it in place on your actual workpiece.

GoatTnder@lemmy.one · 7 pts · 3y

Router and template! Use a band saw or jig saw or even a coping saw to cut out the shapes in MDF or something. Use a 1/2" drill bit as a template and draw on your rounded corners. And then sand or file or rasp them to shape. THEN use a flush trim router bit and go to town!

Arete@lemmy.world · 3 pts · 3y (1 reply)

Could you not just use a router pattern bit and use the actual piece as the template?

legion02@lemmy.world · 2 pts · 3y

This is the way. Tape it down, route it out.

mikiao@lemmy.world · 2 pts · 3y

If you have a disc sander, you could make a jig that has a peg sticking out that you rotate the shape around the hole. Something that looks like:

https://imgur.com/a/pOtxIGJ

softsoupcat@lemmy.world · 1 pts · 3y

If you don't care about being perfectly exact you could use a Shinto rasp. Very effective and cheap