John-

According to the PEX stuff I've read there are two permanent ways to
make the connections.

1) Metal frings & a crimper
2) PEX doubler rings and a tube expander tool.

To make the connections using the expander method

1) slide a "doubler ring" over the end of the tube
2) inset the expander tool into the end of the tube
3) expnad the tube
4) qucikly insert the fitting
5) the tube & doubler ring shrinks down ove thre fitting

the expander method takes advantage of the shape memory fo the PEX
material.

one comment that I have is,: the expander method fittings muct have a
different od thatn the fitting for use with the crimper & rings.


By hand expanderf I mean one that is done by hand. Wirsbo make a
pneumatic & a battery powered expander. Unfortunately all three
systems use different expander hads!!! These both are really pretty
spendy


I just bought a hand actuated expander. on eBay. I have les than 50
connections to make.

Why the concern about PEX/ perfomance (leaks?) or chemical safety?

I'm pretty old school on a lot of stuff. I use EMT or flex w/
THHN/THWN wire. I usually use copper tube. Two contractor friends
swear by PEX, we'll see.

cheers
Bob