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PVC Basic Questions

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Old Man James

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I have a couple of questions about PVC joining; I did take a look at previous posts but over 8K threads just overwhelmed me so forgive me if I'm repeating some things. I'm new to this forum and want to see how I fare with these basic questions. I'm doing some simple joining of some 2" pipes for a large irrigation project and while I have done some PVC work in the past, I thought I would refresh and make sure I'm dong things right. I have read a few posts referring to teflon vs pipe sealant and found some thoughts I was interested in.
1) Obviously, threaded joints involve some method of sealant and I have a bottle of Leak-Lock that I have used for metal pipe threads and am very satisfied with its performance. But I have (for some strange reason) not used it for PVC. I looked at their site and some You Tubes about it and everything (and everyone) says it works great as well for plastic (PVC) so I wonder if anyone here has used it and how it performed? I did see where some state they NEVER use Teflon on threaded pipe joints while others say that if you wrap it well with Teflon it seals well (?)
2) Regardless of how you seal, how much tightening pressure should you apply to make the joint tight? I've seen some posts that said 'hand tight' and others said 'pipe wrench tight'. In the past, I've used 'hand tight + 'quarter turn' and haven't had a leak - but - this is a big project with 2" pipe and I need some pro guidance about 'how tight is tight'? I don't want to over stress the threads but don't want to go back and re-tighten joints. Is it different between Teflon vs sealant?
3) I was looking closely at some of the pipe pieces and how they mounted on various fittings (sleeve joiners, angles, and adapters - smooth-threaded). I noticed that the smooth pipe piece did NOT seat all the way down to the bottom of the fitting but only about half way down where it got tight. Is the fitting tapered from top to bottom? Does the solvent glue dissolve the PVC a little so the pipe seats all the way to the bottom?
4) Some of the joins will require elevation changes so the settings of the angles are critical. Is there a 'slow' setting solvent that allows enough time to align the fittings before it 'sets' and locks the position? I will make 'dry' fittings, mark the matching spots on each, then apply the solvent and line up the marks before everything locks up. I looked at Home Depot and they had both Oatey and Christy's brands - any appreciable difference? One of the Christy's was a 'Red Hot' type and I was told it was a 'combination'; it had both primer and solvent together. The Oatey used a separate 'Primer' and 'Solvent' - two bottles. But the Christy's was a super-fast set so I'm not comfortable with that. Is the Primer, then Solvent method preferred?
Where there are metal valve risers, I'm going to use Schedule 80 fittings as extra protection when the metal pipe thread is inserted - this was recommended by a landscaper friend to avoid any danger of stress at that joint down about 18" to 24" deep (there will also be a 'T-bar' stake to support the riser).
Well, that's about all I could come up with but I would appreciate any 'unasked question' feedback on any points I missed. This project needs to come out without issues so I've tried to cover all my bases.
Thanks to those who took the time to read all the way through and also took the time to respond; very much appreciated.
 

Helper Dave

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1) Pipe dope/sealant on PVC is preferred as far as I know. We never use Teflon tape on PVC.
2) On 2" threaded PVC, I'd go with the hand-tight, and a quarter turn with a wrench rule of thumb.
3) The primer and glue will lubricate the joint, and allow it to slip all the way in.
4) Use the separate primer and solvent. Don't worry about setting time to adjust your angles too much. "Cheater" marks aren't a bad idea (mark the pipe low enough so you don't lose your mark slipping in the fitting), but you've generally got plenty of time to adjust. If you really screw up, get a wrench on it, and twist it apart. You can do this up to a couple hours after the joint was glued if it's not too cold where you're working (cold makes the glue extra tacky).
 

Jeff Handy

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Helper Dave, all good stuff.

Make your Sharpie line up marks allowing for full depth insertion, not dry fitting depth.

Yes, after priming and gluing both pieces, they will slide in all the way.
Be forceful, give a slight twist as you go if possible.
And hold together for longer than the glue bottle says.
Sometimes five or ten seconds is enough, sometimes thirty seconds, observe the fitting and quickly push it back in if you see any backing out.

Unless you leave sloppy edges and burrs on cut pipes, or you are too poky and slow getting them together, they will go all the way to the bottom.
 

Old Man James

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Thanks for the replies; much appreciated.
I referred specifically to the 'Leak Lock' brand; does anyone use that or know if it works well?
 

Old Man James

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OK, first lesson. I had to spend the whole morning gathering parts so it wasn't until 2pm that I got to try to assemble a threaded collar to a short piece of pipe. We are (for us) having a HOT day (70-71) and I'm working in full sunlight.
Ir was interesting to closely read the instructions on the Purple Primer and the Solvent. The Primer wants me to coat the socket of the collar first, then the pipe, then the socket again. So, it's socket-pipe-socket. The Solvent wants me to coat the pipe first, then the socket (not too much), then the pipe again. So, it's pipe-socket-pipe. Each is just the opposite of the other.
Well, the Primer went OK.
The Solvent, not so much. After the second coat of the Solvent on the pipe, when I (quickly) inserted the pipe into the socket, it stalled about half way down and I had to really FORCE it down to the bottom (I thought it might not go, so I put a board over it and put full body weight on it and held it for about a full minute). When I held it up to check, it looked like it was seated at the bottom (according to the inside view) but it appeared to fall about 1/16" short, according to the black mark on the outside. It seems tight and secure so I think that joint is OK.
I was under the impression from the replies so far that the pipe and socket would just slide together easy-peasy and I would have enough time to twist them together and align them, if needed. In fact, both the bottle instructions and the replies indicated I would have to hold the two for awhile to prevent 'push out'. No 'push-out' here.
My concern now is that it is too hot to mount the 45 elbow in this heat as I won't have time to align the outlet side to the proper elevation mark before it all sets up and it may not even seat all the way down to the bottom of the receiving socket.
Apparently, the heat of the day is accelerating the 'set' of the solvent (?)
Any thoughts or comments (please)(?)
 
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