Does anyone out there know how Real Model, Blast etc. make the bulges on their AM wheels?
When I was doing aircraft I'd either sand the bottom flat and/or hold the wheel on a hot iron for a while.
Thanks
Bill

I've always done the hot iron method and I get nicely bulged sidewalls from that. A little side to side rocking ensures the bulges appear on the sidewalls. I have ruined a few tires on occasion, but not in a while (practice makes perfect. ) Sanding just removes material creating flat spots with no bulging; when it's heated, all the plastic has to push up somewhere, creating the bulge. I have no knowledge of how the manufacturers do it, but I'd bet the masters are simply created round, heated and pressed to create the bulge then the resulting bulged tires are used to cast the parts we buy.

I suppose you're right especially if the masters are made of styrene. I have some old wheels I think I'll try it to see what happens.
Thanks
Bill

Actually, sanding a small flat spot is perfectly correct for pre-1970's tires, as properly inflated tires didn't bulge. The bulging tires we see on today's vehicles are radial tires, which are structurally different from earlier period tires. That's why there was so much griping about the bulging tires on Dragon's M2 Halftrack--they looked half flat.