My son was given a motorized adjustable height desk frame. I was damaged when something fell on it. (Hurricane)
He disassembled it and found a broken threaded piece with triple internal threads.
When I saw this, I thought it was a lost cause, as the part is not available to buy.
The part has a triple internal threads, we wrapped three wires,copper, green and gray to figure that out.
My son drew it in Fusion 360 and used the 3D printer at work to make the part.
It took three iterations, before getting the threads right, but when done the internal threads were amazing.
He also had to make a few other parts, (guides and slides).
So he got it all working well. Now he is building a butcher block style desk top using Sapele wood.
This is his first butcher block build so he made two smaller pieces, a shelf to set his desk top computer on and a slide out shelf. He learned about picking/matching grain on those.
He built a jig to do a a bit of joinery, but still end up hand planing the edges to get a better fit.
Now he has cut and glued a 28" x 66" desk top. He will use Danish oil as the finish. Here's the unfinished desk top.
I think it looks great!