Here are a few WIP images of my steampunk basing and troop filler. The concept was the deck or internals of an ironclad with a few open vats that would lead to broadside magma cannons or steam boilers (also to tie in the basing of other units in my army). The troop filler pieces are supposed to be a weighted personnel platform to lower divers into the water, a capstan, and a torpedo repair bench.
For materials I used MDF, watch movements, clock gears, wire mesh, various wires, and a Saran Wrap metal tear strip for spiky trim. I also used baking soda sprinkled over superglue to provide a little ashen texture in spots, particularly to break up the larger areas of MDF or cover unsightly gaps. Tossed on a few rivets to finish them off. These were a fun salvage project and well worth the effort (easy to paint too).