Thank you! Successful repair follow-up
This is a follow-up to my post from last year about repairing a lamp with some broken specialized screws. I eventually decided to go to a local makerspace and take some machining classes. After some time with the lathe, a drill press, and tapping station I was able to make some stainless steel replacements re-use the old set set screws from the old broken parts. Special thanks to u/iKorzo for suggesting using M3 thread adapters from McMaster-Carr, this saved a ton of labor and expense.
A few of my takeaways:
Figuring out what existing parts can be adapted for a repair is a doggone superpower, if you are a mere mortal like me find someone like u/iKorzo who can advise you on this. My machine shop teachers at the makerspace were also super helpful.
Taking time to make and print out a good CAD drawing is incredibly helpful for getting advice from other people and keeping track of things in the machine shop.
Always use "tap magic" (cutting fluid) and a tapping station for tapping stainless steel, it's very easy to break a tap when free-handing. Thankfully this only happened to me once.
Tiny little pieces like set screws are very easy to lose, thankfully this did not happen but I had some close calls. Always put them back into the original part or somewhere they won't get lost.
Always double check the drill size for cutting threads, on my second go-round I forgot that M3 threads need a 2.5 mm hole not a 3.0 mm hole. I actually got it wrong again because I looked at the thread form tap size (~65% thread) and made a too-big hole a second time. I got it right the third time. The nice thing about the hex thread adapters is they have six sides so you get six tries.