Unglueing PVC fittings

[jimc]

Is there a tip on pulling apart glued up PVC fittings.

In my infinate wisdom I have glued up a complex series of connections and put one on 45 degrees out.

I have used the pink primer fluid on both surfaces and the blue glue on both surfaces.

Where the correction has to take place, the inside of the pipe is not readily accessable.

Am I stuffed and have to replace that section?

[Fossil]

There is only one way from my experience and that is to burn them apart. A good gloop of glue on the inside of joint you want to get apart. Light her up and let burn for 15 seconds or so. Get a strong screwdriver down between the flange and pry apart.
You have limited access to the fitting you want to separate, so you may haver to saw the whole lot open before you burn, which may sacrifice one fitting.

Don't worry........ everyone who has done pvc has screwed up the same way as you, sometime or other.

[davo453]

One of my many jobs in the distant past was making custom spa baths and tubing up the jets and pumps using PVC.

Sadly if you've let it dry for more than an 15 Min's or so forget it. You can sometimes cut through the tube and pry it out of the fitting, but that usually creates a bad seal when you re assemble because the glue melts the plastic to make a join.

Fossils way sounds interesting but pretty drastic and I'm not sure what you might end up with anyway. I have a picture of a smoldering bubbling heap of plastic surrounded by the charded remains of a shed

Put it down to experience and buy some more fittings.

Cheers

Dave

[Ashore]

Learnt my lesson years ago now I dry fit and mark with a felt pen accross the joint, one line for the first two on the second and so forth.

[Skew ChiDAMN!!]

I also use Fossil's method.

I used to use just a bic lighter, but quickly discovered they've a tendency to overheat and "pop the top." Almost as big an eek factor as feeling the TS blade tipping your fingernail... :eek:

Jimc: yeah, you'll probably have to cut off and replace something. Hopefully there's a straight between the two fittings... doesn't cost as much to replace.

[dman]

I have recently successfully done this on PVC pool fittings installed years ago. I cut off the offending fitting at the join, and using a hacksaw blade, cut the fitting I was removing 0 ie the inside part of the join. The cut was longwise into the join. Then using a small flat screwdriver, gently levered off the fitting at the join. I had to slightly hammer the screewdriver to get it between the two layers.
The real key to this is reinforcing the outer part of the fitting. To do this fasten a radiator clip (or two) around the outside to stop the outer part breaking as you push the screwdriver in.

I was told this method by an old experienced guy at the pool shop I went to (expecting to have to buy heaps of bits and do lots of digging). It is not always 100% successful, and you have proceed carefully.

I was initially sceptical, but the alternative was the heaps of digging and lots of bits thing, so I had nothing to lose - but it worked well.

(maybe you could soften the join using the flame method as well...)

[chrisp]

I haven't any tips on how to separate glued PVC fitting, but I have used heat to form PVC pipe into a particular shape to serve as a fitting to suit my dust collector.

What I would like to point out, for those who are unaware, is that heating PVC can release toxic gas.

Bill Pentz, on his web site, discusses the danger:

http://billpentz.com/woodworking/pvc.html

Chris

[soundman]

I have sucessfully seperated pvc fittings in the past using and electric heat gun ( no it not a hair drier dear ).

sometimes they come apart reasonably easily sometines you have to sacrifice one half of the joint. try to concentrate on heating the joint and not the plastic arround it, wet rags can help.
Then with a bit of luck it will twist apart. real stubborn ones poking a screw driver in the joint may be needed but there is the the risk of buggering both bits.

Care and patience are the words of the day.

The burning glue thing I recon is a string of accidents waiting to happen.

you probaly could do this with a gas torch but a heat gun is far more controlled.
cheers

[Skew ChiDAMN!!]

I have sucessfully seperated pvc fittings in the past using and electric heat gun ( no it not a hair drier dear )
[...]
Care and patience are the words of the day.
[...]
The burning glue thing I recon is a string of accidents waiting to happen.

Most of my encounters with seperating pvc have been in cold, wet crawl-spaces under houses where all plumbers called out have taken one look and quoted exorbitant prices. (Not that I blame 'em!)

An electric heat gun would be more of a hazard in these conditions. As you said, care and patience.

[Wombat2]

The burning glue method is brilliant ! For years I've been discarding misjointed connections till an old plumber told me the trick. Cut the pipe off level with the joint. Paint a good coat of glue around the inside and set alight - if you can point the opening upwwards so in burns evenly all round so much the better - when it burns out (without starting the plastic burning quickly get your screw driver in and pry out the short piece of pipe. The pipe softens more than the fitting so little effect on the fitting - works every time and no more wasted fittings

[Mike T]

I am with Wombat2. I have done probably a hundred like that except I found pointy nose pliers give the best result by pushing the point in between the fiting and pipe and then rolling the piece of pipe up. This did not damage or score the inside of the fitting as much. On a tough one though the only way is with the screw driver.

[technocat]

There is a way of removing glued pvc pipe from inside a collar. Heat is the answer and this can be achieved by a small butane pencil torch or a hot air gun such as a Leister vinyl welding gun. You need to cut and remove the male pipe a few millimetres from the edge of the female collar. Then with the torch heat inside of glued section about 10 mm wide till it starts to form small blisters then use a stanley knife with a hook blade and score deeply into softened PVC from inside to outside edge, the out side collar should be still quite hard so blade should not go through both layers. Repeat process 25mm to 50mm away from inititial cut. Warm segment up with torch and insert a kitchen knife blade between two layers and prise out the PVC needs to be soft to do this. This will leave two exposed edges. Heat one edge and prise off with knife blade until you can grip inside section with pliers not fingers as it will be damn hot. Heat inside slowly working around inside of pipe taking care not to burn collar and pull away with pliers, if heated well the inside section will peel away leaving no damage to collar. Clean up with some 80-100 grit sandpaper and prime with acetate. This method works.