Work in progress: Table corner protectors

We have a removable table that we put on our pool table when we want to use it for food service or craft work. I recently re-covered it with a padded plastic material because the old stuff had shredded over the years, mainly when it was dragged away and stored in the garage. I don't want the new material to be ruined right away, so I decided to 3D print some removable corner protectors for when it's not in use.

I had made a much smaller protector for a metal edge on my workbench and thought since it was parametrically designed I could reuse the file. Unfortunately the previous design assumed equal thickness on each leg. Due to the table top being effectively "upholstered", the thicknesses vary, and so my first attempt wouldn't stick on one side, and crimped the plastic on the other. A millimeter or two difference is needed between the legs. Fortunately I had recently bought an electronic caliper which made this all so much easier!

I ended up redesigning the whole thing with more variables. I also found a subtlety of CAD design. I had done two simple extrusions for the two legs. Because the resulting file is the union of all the bodies, the thickness of the overlapping center section was always the narrower of the two (i.e. the largest body in space), so it was never going to fit. I had watched a tutorial on Autodesk's web site showing how there are multiple ways to accomplish the same geometry, so I redesigned it in three bodies with a subtracted channel instead of a single extruded profile. My third try fit perfectly!

I realized that all four corners would be different, so I'd need to mark them. Rather than write on them with a Sharpie, I decided to learn how to use Fusion 360's text feature. I did reverse-embossed (subtracted) lettering. Cool! This one is only cut halfway, but I rather like having them cut all the way through, so I'll do the other three that way.

These are some of the largest objects I have printed so far. At low quality, with 20% infill, this one took over 3 hours. (I've had longer prints on other things, but at higher resolution.)