This is one of those I think I can do so why not try. I make a fair number of jigs every year and sometimes they need knobs. Knobs can run from just a few $ to say $5 and most times I need more then one. Then there is shopping for them, limited selection locally and ordering takes time.
A simple solution I’ve used in the pass deals with a hole saw, to make a round knob then a drill with a bit just the right size to allow the pounding in of a nut or bolt and then a lot of times me tossing that and installing a store bought one when they arrive.
Having a SO changes everything. So my first attempt at this I made some round knobs to take some 1/4-20 bolts and or nuts depending on how deep you go. Nuts need about 7/32" and bolts 3/16" but check what you have before moving on with the job. I used some baltic birch plywood in the 1/2" range but a hardwood or even a soft wood could work.
This is the concept, you may chose to do it differently or if you have other equipment then adjust for what you have. I started with this round knob:
Then added these:
This last one has a problem, don’t get an output from the plug in… will try to draw it again as it pretty much has to be the outside bit that is the problem, the inside has worked now several times. It maybe that it has to deal with how I made the shape???
The one file gives you several option as far as size goes. Of course the inside needs to be done all the same and this is designed as a 1/4 x 20 fastener but the outside can be cut inside for a smaller knob, on the line for a bit larger knob or cut outside for a little larger then there is bit sizes and off-set changes that can be made.
I also made some covers that can get glued on, this is a mater of just cutting some thinner plywood the same way you do the outside cut and if you want to capture a nut the cut the center hole and there you have it.
Here are a few pictures of the 6 round ones I did.
So this is the concept have fun with it.
Great to have a way to get from sketchup to the SO!