Installing rivets: pre-heat or cold!

[steve hackel]

Based on your experiences with body rivets for sub rails, door sills, floor
pans and any odd brackets, do you heat them up or try to install them cold?

I do have an aircraft rivet gun - not a muffler tool - and the correct tools

for forming the rivet heads, but even getting them to fully compress much less form a correct looking head is nearly impossible. I'm looking for someone

that has been successful with their installations using either method, and

not just what might seem normal .... Thanks, Steve