Thanks artoodeeto, I'm having fun with it.
I'm busy working on another update but I need some help from folks in Canada or Europe (maybe even the US). I need brass metric socket head button M4 screws like in the picture below. 25 & 40mm length would be ideal. Mcmaster's doesn't have them and I'm striking out at local shops.
I've found M4 hex bolts locally and had some partial success with soldering button screws to threaded rod but neither is ideal. Anyone know where to buy the button head ones?