[bidwin]

Is there some reason plumbers putty can't be used on threaded PVC connections? I have some LDR putty that states not to use on plastic on the container, but not why.
Thanks,
Bill

[massplumber2008]

Hi Bill

It is the petroleum component in plumber's putty that can cause a chemical change to plastic materials and actually degrade the PVC. Further, when you try to use the putty on the threads it tends to bunch up as you turn the fitting into the accepting fitting, so it is simply not something that is advised if you want to do the job once and forget about it!

Mark

[speedball1]

Also, don't use thread sealant on p[lastic56threads. It makes the threads slip against one another causing a poor grip. REgards, Tom

[bidwin]

Thanks for the responses, guys. I'm having trouble keeping a sink trap's nuts tight. I've used putty on trap joints in the past and never had trouble with them, but I guess now I'll look for something other than putty.

[speedball1]

Be sure that you haven't started a cross thread. A cross thread would give you the problem that you have/ Is it the joint that joins the "J" bend to the piece that enters the wall? Let me know, Tom

[talaniman]

What schedule and class of PC pipe or type are you using? A match can be found for it. Some set quicker than others and many come without a petroleum base.

[massplumber2008]

There is no putty that is correct for this application. In this case, wrapping some Teflon tape around the threads should suffice to assist in cinching the nut down...a little Teflon pipe dope could be helpful here as well!