I thought I'd add my two cents. Going back to the OP , I also use wire and other type of metal shapes for strenght in thin stuff. My scratch building is not as advanced as the wonders one sees here but it has similar roots. You don't have one, make one. I also use store bought structural styrene and brass but I seem to find a lot of it in discarded everyday stuff. So I maintain a well stocked shape box. I have a Taig Lathe which meets most of my needs. I still have to learn how to index holes. At least I think that is what it's called. Like the hole pattern in a circle (rim, flywheel, flange,etc).I built a lot of tools and machines for my engine shop dio using junk mixed with styrene. Or I'll use an existing kit part as a base and start from there, i.e. the Big Al AC truck engine. I have scale charts all over the wall as well. I second the comment above that this gets to be somewhat addictive.