Re-gluing PVC Pipe

[MoonRiver]

This goes along with my connect 2x4 to slab question.

I'm building a PVC greenhouse out of 3/4" PVC pipe. I have pounded rebar into the ground on both sides of a concrete slab. I am connecting 2 pieces of pvc pipe with a x connector and then sliding each end over a piece of rebar.

Each piece of PVC pipe is 9' giving me 18' bent across the 2 pieces of rebar. Most of the connections are holding, but a few busted loose. I tried regluing them and that didn't hold. I tried regluing using a new piece of PVC with the old x connector and that didn't hold.

Is there a trick to regluing PVC?

Most of the frame is connected and glued together, so I need to reuse the x connectors if any way possible.

[Curtis B]

Did you use the cleaner/primer? Did you hold them together until the glue set? Whas it wet(as in water)? When it comes to pvc, I have never had a joint come apart that was properly glued together.

[arabian knight]

Are you using the cleaner/primer? That is the trick use a lot of cleaner to soften up that old glue. ( And the PVC will also get soft just a tiny bit ) Then put on glue on both joints. Twist the pipe just a little, and hold it for a few seconds to let set.

[Homesteader at Heart]

Check to make sure you are using the right cement for the type of pipe. The information below came from http://www.ppfahome.org/cements/faqcements.html.


What cement should be used for PVC, CPVC and ABS pipe?

It is important to carefully select the proper solvent cement for your application. PVC cements should be used for PVC pipe and fittings, CPVC cements should be used for CPVC pipe and fittings and ABS cement should be used for ABS pipe and fittings.

[davel745]

Just a thought. I would use purple primer and blue PVC cement. I would glue the two pieces together flat then bend it over the rebar dowels.

Dave

[arabian knight]

How many of you know this?
For somebody that is going to use a LOT of PVC or CPVC
There is something way cheaper to use then that "Purple" stuff.
Way cheaper.
And that is go down to your local hardware store and but a pint of MEK. ( Methyl Ethyl Ketone. ) That is what that Purple Primer is.
The only difference is it has the Color in it.~!
And the ONLY reason the Primer is colored is so that the "Plumbing Inspectors" can SEE you used the cleaner, and that is that only reason for the cleaner to Colored. As it is mostly MEK with color purple added. There are 2 other smaller amounts of petro chemicals, but just plain MEK works just as well only not Purple.

[davel745]

Thanks, Great idea I will remember that.

Dave

[MoonRiver]

Originally Posted by Curtis B

Did you use the cleaner/primer? Did you hold them together until the glue set? Whas it wet(as in water)? When it comes to pvc, I have never had a joint come apart that was properly glued together.

Yes, I used the cleaner and glue. The problem may be the temperature. When I put stress on the pipes (bending them to make the frame), one side stays glued fine and the other side breaks loose. I haven't been able to glue any of them back so that they held.

[tiogacounty]

The comments on purple primer are correct. It's only purpose is for inspectors that are too lazy or dumb to check if the joint was primed. Other than that it does nothing but stain and ruin everything it gets close to. I occasionally use a factory certified fiberglass tub repair guy. He loves purple primer. Nothing like a $200 service call to clean and buff a tub with purple splatter all over it.

[tiogacounty]

Originally Posted by MoonRiver

Yes, I used the cleaner and glue. The problem may be the temperature. When I put stress on the pipes (bending them to make the frame), one side stays glued fine and the other side breaks loose. I haven't been able to glue any of them back so that they held.

There is a cold weather PVC cement available. I use it to rough in houses in the winter and it works well. A connection that is properly primed, glued with all weather glue and allowed to cure for 1/2 hour should be stronger than the surrounding pipe.

[SteveO]

In your next adventure in hoop houses I would suggest electrical conduit it has a thicker wall thickness and the couplings are deeper I believe. You could also heat it up and prebend them before installation.
just my .02
Steve

[tiogacounty]

Originally Posted by SteveO

In your next adventure in hoop houses I would suggest electrical conduit it has a thicker wall thickness and the couplings are deeper I believe. You could also heat it up and prebend them before installation.
just my .02
Steve

Good points. Conduit comes with a "bell end" which is essentially a coupling formed by flaring the end of the pipe. Some companies make smaller pipes sizes with a really generously long bell, like a 3" socket on a 1" pipe. If you try to heat bend pipe, remember to duct tape the ends shut before you start. The expanded air trapped inside acts like a form and keeps the pipe from kinking. Another possibility is to use pressure couplings. These are the same size as schedule 40 fittings, but stronger and longer. Definitely a better choice for butting two pipes together when making hoops.

[PD-Riverman]

I can not figure out why your joints are coming loose. I haved worked with alot of pvc and don't ever remember a joint coming loose. A connecter should break before the glue comes loose. I know you are using a cleaner, but do you put glue inside the X connecter and on the pipe before you put them together. Also when you put them together do you stick the pipe in the fitting then turn the pipe left or right maybe about 1/4th the way around before the glue sets? If you do all this---you must be got some bad glue.

I built a green house like you are talking about, but I bought 20ft pieces of sch-40----measured exactly 1/2 the length of each pipe before I bent it and made a mark all the way around the pipe. Then I bent all the pipe into place, then I took a drill with a 1/8th" bit and drilled a hole in the bottom side of each piece of pipe right on the line in the middle(drill just through the bottom side) then I took another 20ft piece of pvc and marked it the exact spacing I had my "ribs" apart-----drilled a hole a slight bit bigger than the 1 1/2" screws I was using---I drilled the hole all the way through this pipe----Then I slid a screw into the drilled hole---through this pipe, held it up under the pvc ribs---stuck the point of the screw into the 1/8" hole that was drilled earlier, then tighten the screw and did all the other ribs---mine was 30ft long so I had to add 10ft to the length of this pipe. Doing it this way did several things-----Saved buying all those X fittings, Saved having to glue up all those X fittings, plus if I wanted to take it apart it was simple. Good Luck


Ps If you really want it be more solid----mark the ribs at 5ft, 10ft and 15ft---then use 3 pipes under the bottom side instead of just the one in the middle.

Originally Posted by MoonRiver

This goes along with my connect 2x4 to slab question.

I'm building a PVC greenhouse out of 3/4" PVC pipe. I have pounded rebar into the ground on both sides of a concrete slab. I am connecting 2 pieces of pvc pipe with a x connector and then sliding each end over a piece of rebar.

Each piece of PVC pipe is 9' giving me 18' bent across the 2 pieces of rebar. Most of the connections are holding, but a few busted loose. I tried regluing them and that didn't hold. I tried regluing using a new piece of PVC with the old x connector and that didn't hold.

Is there a trick to regluing PVC?

Most of the frame is connected and glued together, so I need to reuse the x connectors if any way possible.

[rzrubek]

I had the exact same problem when i tried to build a hoop house the way you are. I gave up on the 4 way connectors and used 20' lengths and built a A frame with a center ridge. You can see it here. If you can't haul the 20'er's, then do like the others mentioned and get electrical conduit with the bell ends. Good luck with the project.

[agmantoo]

If schedule 40 pvc pipe is specified, I believe the wall thickness are the same and the bell ends are available in both conduit and plumbing piping. The Rain or Shine cement will hold better and cure quicker IMO

[WIPPdriver]

Use primer and "hot" blue glue. Will work great!