3/8 ths tend to crack. Go very slow. I use it all the time.
Yep. Even with soft tubing I tend to anneal it. You can silphos over crack but a wave of the torch to soften it up and you'll never have to. I've always had/used the mastercool Hydra Swage kit. I wish I'd known yj made one for that price.
I paid just shy of $700cdn for my Mastercool kit however it goes up to 2 1/8
As a contributing comment only, I would consider annealing the tube end before this operation.
In my area there are so many different suppliers of copper and if a good quality one (usually cheaper) is bought, bending will cause the tube to split.
Heat the area and quench it quickly and that will soften it up making it easier to work with. It works for me.
I would like one of theses kits, but cannot justify the cost.
I have a cheap Chinese one, US$99 plus a bit of freight. Easy to use and control.
Only issue and a minor one, is that the expanding pin, can work itself free. ( when the tongue and groove line up the pin can be removed, some tmes it lines up by itself)
As most the copper is thick walled and can be quite old, I to tend to heat before expanding, also tuning the head half way through the swage, stops the splitting