The $29.99 all-metal desktop Stirling engine kit is one of the simplest. It can be assembled in 15 minutes and is recommended for ages 14 and up. Also for $29.99 is the Exploring Kid Steam Engine Kit.
Kitbashing is taking miniatures from multiple model kits and mixing the pieces together to create something new. But it’s nothing like building with Legos, since those tiny little arms ...