How big of a pipe? Like sewer abs pipe?
Not sure how to put in the thread adapter, or even what it is... end caps make sense but how do you add nipples that don't leak?
Drill a slightly undersized hole into the pipe cap. Probably best to do this after you have glued on the cap. And in the area where the cap and pipe overlap and are glued. That way you have double the thickness of plastic.
Screw the brass fitting into the hole. It will make it's own threads into the plastic.
Remove the fitting, coat the threads with silicone adhesive. Re-install the fitting. Let cure completely.
This works for making reservoirs for pressure up to several hundred pounds. It certainly should hold up to the less than 30 pounds of vacuum our systems must produce.
89 F250 XLT Lariat 7.3idi C6 4WD
92 F250 XLT Lariat 7.3idi E4OD 4WD
Last edited by Selador; 05-19-2019 at 12:09 AM.