I have an interesting question .How many times have you looked for parts for that armor model , that car or plane model or ship model and just couldn,t seem to find it ? The P.E. stuff can get expensive . Now here,s a thought , spurred by a flea market find .Try yard sales and make sure to check ANY loose jewelry offered for sale .WHY ? well , the best looking spoked ships wheels (1/48) and screws (1/48 and 1/200) were found in the earring bunches .Yup ! earrings ! Now I have also seen little shovels and stuff (pioneer tools for a tank ?) and also little FORD and CHEVY dog dish hubcaps (1/25). The other thing I noticed was certain toys though broken may have parts you can rescue for models. Give it a try . tankerbuilder P.S. The four bladed screws for the ARIZONA came from such a source and it sure beats scratchbuilding or buying the expensive brass ones.
Sprockets can be sourced from watches and watch and clock parts. Back when digital was not even heard of clock and watch parts used to be available in huge bags. For a couple bucks you had a lifetime supply of them. I bought one bag and it lasted me years. I used them for trim wheels in cockpits, cranks on machinery and even gears on farm implements. Today if you can find these same bags they are pricey as everything now is electronic and sealed.
I work in a major Denver hobby store and I often say “think and look outside the box”. We sell trains,planes,plastic models, diecast, rockets, everything…just go look around the shop and you will be surprised at what you find…Lionel brake wheel makes a great small spoked wheel.
I use craft stores, like Michael’s a lot. Small beads, fine jewelry chains, fine wire, and lots of other gadgets can be used for a lot of model parts. Browse through one of those stores and look at what is available. Neat bases, too.
That’s “Gizmology 101”… [;)] More model detail-parts are found in “non-traditional modeling” locations than in a hobby shop and are usually free, or at least only a few pennies per part…
Old model model railroad layouts and broken trains, broken farm toys, other toys, electrical components, jewelery pieces, “hardware” drawers, bric-a-brac, this-n-that, etc…