I have installed two new 50mm wastes in my kitchen sink that connects to a setup like in the attached pic.The wastes are exactly the same as the ones I am replacing and on the mainline I have replaced the washer at the screw join.My issue is that now both left and right screws are slipping when being screwed into the new traps. I can get them just to the point where they are hand tightened with about a 1/4 turn more to go but at that point they slip and I have to start screwing them in again. I have screwed them as far as they will go which I guess I can live with but I'm just waiting for the silicon around the traps to cure before doing water testing but does anyone know why these new traps would be slipping?
>>2384365Threads are slightly off?Limited plumbing experience but what I have seen is that hand tight should do it for drain lines.
>>2384371I thought that maybe the threads were off but I disconnected everything and tried again making sure everything was aligned.I had also previously taken apart and reassembled the secondary trap while I was figuring out the issues and at no point did it slip so I think I'm aligned.I am only hand tightening, by 1/4 extra I mean still using hands only not with grips or anything.Is there some sort of overtightening prevention mechanism that will slip once it's too tight? I doubt it but I am just a diyer so have not much experience.
>>2384365The terms you are using are confusing in context...the pipe shown fits to each sink's strainer fixture either directly or via a tailpiece pipe extension, and the bottom outlet attaches to a single trap. Regardless, none of those connections should need silicone, they use compression washers and gaskets to seal.Because of that and for ease of assembly the threaded coupling nuts (not "screws") and other parts will often be made of very flexible plastic that deforms slightly under pressure and especially with cheap ones they can indeed be tightend to where the threads will 'pop' past the full tightened position and they are loose again.Also if you mix up the threaded portions of different fittings the tolerances may be different enough to prevent a sung fit and allow that to happen...keep in mind that even what appears to be a complete fitting at the store may have been messed with and parts mixed up when someone unscrewed parts and tossed it back in the bin and someone else reassembled what was there.
>>2384452Yeah, or someone pinched the gasket because reasons.
Im guessing you bought some cheap crap. Try a different brand, sounds like the threads were made to shitty tolerance.>fucking metric fag.
>>2384365wrap the male threads about 5 or 6 times with teflon tape, if no joy, see >>2384602
Thanks everyone I think I have fixed it I will monitor it over the next few weeks.Sorry for getting the terminology wrong. I think also some terms are different in Australia.The wastes/strainers that are the fixtures in the sink needed a silicon seal because they only have a washer/gaskets on the underside of the sink. This is in accordance with manufacturer's instructions. I understand what you're saying about the ones with gaskets on the top and bottom but this one is an older sink.The PVC in the OP pic was the original unit that came with the situation so I got a new one of those that seems to be a better quality. The nuts are no longer popping.But I think the main issue was with the hold in the shelf that the downpipe passes through. It was previously really tight on the pipe passing through it and I think that was slightly linking the pieces in the OP pic slightly to the point where the washers/gaskets in the wastes/strainers were ever so slightly not flush. So I expanded the hole a bit so it's nowhere near as tight and now it seems like everything is right.Thanks everyone for your feedback.t. Metric fag
>>2385037>hold in the shelfhole*