Can anybody tell me what are the typical pressures required to dimple
a skin and also to compress a flush rivet? I know that squeezer tools
are rated at typically two to four tons, but what are the actual
pressures required? I'm trying to work out the dimensions on a hand
operated gantry for dimpling and back-riveting the skins on an RV, and
I don't want to over-engineer the thing too much...

Thanks,
--Max