How to clean glue off PVC pipe

[Lois Lane]

So I messed up a fitting. I did not get the PVC pipe in the coupler far enough before the glue dried. I was able to separate them with a heat gun. I have a new coupler, but can I take the glue off the pipe and reinsert it in the new coupler? Of course the pipe is connected to the rest of the plumbing that I completed a few days ago. I tried scrubbing it with acetone, but you can still see primer and glue and the coupler still will not seat on the pipe fully. Is it critical to seat fully into the coupler all the way to the line in the center of the coupler? Worst case scenario, $10 for new pipe and fittings and an opportunity for more practice

 

[WorthFlorida]

https://www.oatey.com/video-faqs-blog-case-studies?cat=Cements, Primers & Cleaners&type=faqs

More than likely you cannot remove dried PVC cement. The primer can never be removed from any surface. Depending on how much cement was used you might be able to sand it down but both ends will need to be fairly clean. The primer helps start the chemical reaction of the cement with the PVC. It's a chemical bond, not a surface bond. If too much is left on the pipe, the chemical bond will be prohibited. If this is a drain line with little or no pressure, a reglue may work with proper cleaning. You'll know it as you make the joint. The PVC softens the surface of the PVC so there is a little give to get a good mate. The worse is it leaks (drain only) and a redo would be necessary.

 

[Sponsor]

 

[Mr tee]

Sand off the glue. If this is on a pressure system (water, eg) be careful you don't take it down too far and compromise the snug fit of fitting and pipe. This is less important on drains. In either case it is unlikely to be an issue as long as you don't get carried away.

 

[Jadnashua]

The cement is composed of basically two components:
- dissolved pvc
- solvent
When you make the connection, the solvent literally melts the surface, and the extra pvc in the cement helps to fill in any small gaps...then, the solvent evaporates, leaving it welded together...the two surfaces are literally fused together. Prior to all of the solvent evaporating, you might be able to pull it apart, but it can be tough.

PVC fittings are tapered...the pipe can't be fully inserted until you add the cement, which melts it. That taper also helps to ensure it ends up centered and lets you know when it has bottomed out.

There's a difference between glue and cement...glue tries to bond two different materials together, a cement literally welds them together, and the strength there is the original material's strength whereas, glue's strength is itself, and how well it bonds to the different material.

 

[Lois Lane]

Sand off the glue. If this is on a pressure system (water, eg) be careful you don't take it down too far and compromise the snug fit of fitting and pipe. This is less important on drains. In either case it is unlikely to be an issue as long as you don't get carried away.[/QUOTE

 

[Lois Lane]

Thanks Mr. Tee and Jadnashua. By the time I sanded the plastic smooth, my husband had gone to the hardware store and bought a new one. Next time I will let my husband push the two together! Some things men do better.

 

[Fitter30]

A small bevel on the end of the pipe will make it easier to bottom fitting out.
Small pencil mark at full insert depth on pipe.
After gluing and inserting the pipe hold fitting and pipe together for 15 seconds because pipe likes to creep back out.
https://www.amazon.com/TIPU-Inner-O...ocphy=9023792&hvtargid=pla-350606892423&psc=1

 

[Jadnashua]

Depending on how much cement you use, and the orientation of the pipe, it may take longer than 15-seconds for things to stabilize! The larger the pipe, the longer it may take to stabilize as that tapered fitting just acts like a wedge to push things back out. That can be very annoying if it creeps after you think it's solid, and go on to something else. Until enough of the solvent evaporates, the cement just acts like a lubricant...it's literally melting the plastic of the fitting and pipe, so that is part of the issue.

 

[Lois Lane]

Thanks, I love the pencil idea to mark full insertion. I did know about keeping pressure on the fitting for a good while to keep it from pushing out. I think the problem was working overhead with a rotator cuff tear!