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I've been retrofitting an existing PVC irrigation system around my house. Part of that work requires that I work in shallow holes adding T joints and elbows in places where there were none before. In an effort to measure twice and cut once, I've been assembling the system without glue to make sure I have the layout correct. More often than not however I'm running into issues separating the slip joints and pipes despite the fact they aren't yet glued.

What's the best way to separate these joints? Should I be applying some sort of lubricant beforehand (that won't affect gluing later on) or is there a trick beyond forcing things? With too much force I'm afraid I'm going to break pre-existing joints or mangle the existing fittings.

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The best lubrication I've found is some good ol' Elbow Grease™.

Elbow Grease

Actually, you should measure the proper lengths and just cut. Then glue it up and install. You can mark on the PVC how far it should go into the fitting if you want to be really precise. However PVC itself expands and contracts a lot with temperature change and is fairly flexible anyway. So, in my opinion, being extremely precise doesn't mean all that much anyway. Also, The solvent melts the PVC surface to weld them together, so the fittings will likely fit differently while gluing, thus making the dry-fit method even worse than just measuring.

Another solution could be to mark how far in the fitting the piece should go and lay them next to each-other in that position, even tape them together, to check your layout. That seems pretty time-intensive, though. I still think it would be better to just measure accurately and double check your measurements.

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    Decker is right on with this - when you dry fit, the pipes may not go all the way into the fittings.
    – Eric Gunnerson
    Feb 18, 2013 at 3:09
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    PVC fitting are also tapered which makes it hard to get the pipe all the way on when dry fitting (as well as taking them apart after). In addition, if you get any dirt/grit in the hub of the fitting, it will be that much harder to take apart. If you're having a hard time using just your hands, you an use a hammer to tap on the face of the fitting. Do this lightly and go all around the circumference of the fitting. If you hit too hard the fitting will misalign and get harder to remove.
    – pdd
    Feb 18, 2013 at 20:37
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    This isn't super helpful. As a woman I simply have less elbow grease to apply and find that tool use is often worth it.
    – Loren_
    Oct 11, 2017 at 20:17
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    @perilandmishap the moral of the story here is prevention. you should not be dry-fitting, you should be measuring. if you happen to dry fit, then pulling really hard really is the best way to get them apart, since any tools you can think of to use will risk damaging the pipes or fittings.
    – ryanwinchester
    Oct 11, 2017 at 20:56
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If you still can't get those unglued pvc pieces apart, we found that a flathead screwdriver and a rubber mallet help loosen the pieces enough to be able to pull them apart.

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  • This answer actually ANSWERS THE QUESTION! (Worked for me, too, bonus!)
    – Drew
    Jun 4 at 0:42
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Try using a heat gun on the un-glued, but stuck connections. Also, if you need to un-glue a dried connection, using the heat gun gently warm the fitting until it can be pulled away. I've found this to be very effective.

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    Hello, and welcome to Stack Exchange. It isn't clear what you're trying to say here; reformatting and making it into full sentences would really help. Thanks.
    – Daniel Griscom
    Dec 24, 2015 at 14:02
  • Heat expands cold retracts heat to pvc will eventually soften the pipe and fitting enough to let the two separate but the integrity of the pvc will be compromised instead of dry fitting lay the sequential pieces in full fit position a few at a time using the inset marking with sharpie
    – Kris
    Dec 24, 2015 at 23:37
  • I put ice on the inside of the piece that was stuck and within 30 seconds it had contracted enough for me to get the pieces apart.
    – user70708
    Jun 10, 2017 at 23:47
  • An easy way to do this – is using the heat to expand and cooling to contract principle (works quite well) for pulling apart PVC parts that have been put together without being glued. One way to undertake the process of pulling two parts are part (If the configuration is small enough). Is to put the whole thing into the freezer (the coldest part of the refrigerator) for about 30 minutes and then use a blow dryer (hairdryer) on the outside part whilst pulling the inside part are part. Works reasonably well for small configurations. If you're in the field and don't have a handy refrigerator that
    – Norvan Vogt
    Apr 11, 2021 at 2:25
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I had the same problem after doing a dry fit ( in the rain ) and grit/sand got into some of the connections. I tried various methods including heat/ice but none worked on one particular connection. I fortunately had 2 rubber strap wrenches i had brought for some plumbing work and with these i was able to get enough torque to get the pipes apart.

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I think just cutting the pipe and gluing it together is the best way to go in your situation. Dry fitting can still be hard to removed, as you've discovered! Also, PVC solvent does not melt surfaces to weld joints together. In fact it's easily unglued, should it ever need to be.

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    PVC pipes are NOT easily unglued. It requires specialty tools, and the destruction of the pipe.
    – Tester101
    May 6, 2015 at 11:07
  • PVC can be unglued without specialty tools, though they sure make the job easier. The pipe is NOT destroyed, in fact after ungluing it's ready right away for a new pipe to be glued in. More here, if you're interested: pipedebonder.com
    – Travis Griffith
    May 6, 2015 at 16:25
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    the pipe debonder is the specialty tool, and it does destroy the pipe. It saves the fitting, not the pipe.
    – Tester101
    May 6, 2015 at 19:05

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