I'm replacing some sections of PVC hose (1-1/2" tiger-flex) with PVC hard-pipe.
For the the pipe-to-hose connections I decided to use screw-in barbed hose adapters (with clamps), requiring terminal female thread PVC fittings on the hard-pipe. I've followed what I thought to be correct practice - applying a couple of rounds of teflon tape to the male thread, screwing-in to hand-tight and then two more turns with a wrench - but found that hand-tight barely got the thread in half-way and two more turns required quite some force and still left a gap of about a 1/4". Tried with just one round of teflon tape and didn't fare much better.
Seemed odd that fittings from the same manufacturer (Lasco) wouldn't completely screw together, so I checked their website and found they state that teflon tape should definitely NOT be used because it stresses the tapered threads and risks splitting the fittings....yikes !!! Nor should regular 'pipe dope' or teflon paste be used because they lubricate the joint and encourage over-tightening.
http://www.lascofittings.com/supportcen ... lastic.asp
The only thing they recommend is applying a non-hardening thread sealant compatible with PVC plastic.
Are other people following this advice? - the contractor who installed my pool certainly didnt - all of the threaded connections were heavily teflon taped - might explain the several cracked fittings and copious amounts of silicone I found when disassembling the plumbing.
Could anyone recommend a good, PVC compatible thread sealant?