Tools for assembling cast iron radiator sections? Push nipple type radiator

alesage

Foolishly I attempted to remove a couple of sections from a cast iron radiator, which is of push-nipple construction, with rods. I've found good advice here: I see where to get replacement nipples, I'll use a thin bead of high-temp RTV on the flat surfaces when reassembling, I'll test with air and water before returning to service.

What I don't understand is how to get the dang sections all the way back together. Using four pipe-mounted woodworking clamps with as much elbow grease as I can muster leaves a visible crack between sections.

Should I lay in with the mallet? A wooden frame with hydraulic jack? Three dozen strap wrenches? What do the pros do?

I confess that I'm re-using the existing nipples, would that explain a poor fit?

(Posting to MAIN WALL as my searches yielded dispersed hits.)

retiredguy

To put the radiators back together you can use all-thread rod of different lengths to replace the existing rod. When all the sections are back in place you could cut and thread the original rod to the size needed so the rad looks like it was originally or just use the last all-thread rod you used to pull the last sections together and cut off the excess rod. To make the job look professional you could replace the standard nuts with "finishing cap nuts".

Ironman

Yes, you should replace the push nipples and hone their sockets. But I doubt that's your problem assembling it.

You have to keep the sections in alignment while applying equal pressure from the clamps or draw rods. Then, use a mallet with a 2x4 flat against the rad. Keep constant pressure on it from the clamps and alternate blows between the top and bottom.