Summary

I made this rack for my maverick drift car spare wheels/tyres
ive designed it to be stackable so can have rows of 4 in different compounds etc.

for an extra level you can just put 4 more wheels on the topplate,
Or you can print 2 new sides and another top plate to box them in.

will fit wheels of up to about 28mm wide x 65 diameter

All pieces are keyed so easy to glue together.

Print bottom plate upside down (with support)
Print side plates with 'x' on the print bed, radius's facing up (with support)
Print top plate with concave 'key' on the bed (with support)