this guy makes it look easy !!

[brianmcs]

https://www.youtube.com/watch?v=QY_mamm09CM

[NIR]

A scratchbuild from brass sheet with minimal tools, amazing

[Mayner]

Excellent find.

Traditional scratchbuilding techniques and extremely steady hands!!!!!!!!!!!!!!!!!

These days I would struggle to scribe a line against a straight edge let alone use a piercing saw

There is an excellent article in Model Railway Journal 279 on building a GNR(I) U Class in 3mm scale with working inside motion using basic hand tools.

[Horsetan]

Note also the freehand use of the mini-drill. No pillar vice to hold it at 90 degrees! The miniature engineering fraternity would have nightmares!

Actually, there's loads of techniques in here that scratchbuilders commonly use, but very few have time, patience or inclination to film an entire YouTube video showing how they do it....