Hi,
Is there some compound or liquid that I can spray or rub on between
parts that will keep them from fusing from the heat of nearby welding?

I'm welding three pieces of tubing to a structure, and they have to
line up precisely, so I've got to have a shaft holding them in place.
The problem is that the heat causes the shaft to get stuck. I don't
think that I'm welding through the side (I'm quicker than that) but
something is fusing it in place. Any help for this?

Thanks, --Max