What is Solvent Cement?
Solvent cement welds thermoplastic sheets and piping by softening the surface of the material being bonded. Unlike gluing, which hardens to hold material together, the material softened by this substance trades molecules to form a solvent welded joint that has the strength of the parent material. Primers and proper preparation allow the solvent to form a bond without contamination from grease, inks and oils. beyond proper cleaning, the type of solvent cement must be compatible with the thermoplastic or the surface of the plastic will not melt correctly and the joint will not have a strong bond.
A list of compatible plastics will be listed on the solvent cement canister label. The three-letter designation listed on the canister label must match the three-letter designation printed on the surface of the thermoplastic to ensure a finished solvent welded joint has the strength to hold the amount of pressure required of the connection. Common three-letter plastic identifications are polyvinyl chloride (PVC), chlorinated polyvinyl chloride (CPVC) and acrylonitrile butadiene styrene (ABS). One thing all thermoplastic solvent cements have in common is the strong fumes emitted from the chemical during use.
The chemicals used to soften the surface of the three common thermoplastics have a strong odor that can become overpowering in the confined areas in which they are used. Proper ventilation will provide a constant flow of fresh air that keeps the solvent fumes from building in the area and reduce the chances of the user succumbing to asphyxiation. When a canister of solvent cement is opened and a strong odor cannot be smelled, the liquid cement inside the canister may have dried out or been frozen at one time.
Common signs that solvent cement has gone bad are a gel-like consistency, lumps floating inside the canister or a dauber that cannot be removed from the canister. Unlike paints or other solvent-based materials, solvent cements cannot be thinned to bring them back to their original consistency. Thinning this substance will cause the solvents used to soften the surface of plastics to break down and not allow a strong bond to form between the pieces of material. Cold is another factor that inhibits the cement's ability to bond with plastic. The optimal temperature to apply solvent cement to a thermoplastic will be printed on the canister label, and the product should not be applied in temperatures sitting outside the optimal temperature range.
What chemicals make up the standard ABS solvent cement? It would help me a lot if someone could answer that.
My son and I are planning a sort of science project whenever he is out of school this next summer. Basically, he wants to make some kind of a waterfall out of some PVC pipe and a piece of plexiglass. We saw something similar the last time we were at the science museum, so we're trying to recreate it.
My main question is, how much piping will one can of PVC solvent cement hold together? Does anyone know the relative cement price, too? I know the type of can it comes in, but I have never really looked into how much use you can get out of it or how much it costs.
Whenever you are applying it, is there any special way to do it? Do you need a lot, or will just a thin layer work? What happens if you get the cement on you? Will it hurt your hands, or just be a sticky mess? How do you get it off?
@titans62 - I am not really familiar with the uses of ABS. From what I have seen of it, it usually seems a little bit more flexible than PVC. For some reason, it seems like ABS is more often colored, as well. I would have to assume you need a special ABS solvent cement for that compared to PVC.
As far as PVC versus CPVC goes, I don't know too much about the manufacturing process, but I do know that CPVC is usually called "hot and cold" piping, and is what is used for things like dishwasher hookups. It is usually more beige in color than the white of PVC. I have installed both PVC and CPVC pipe, and you can use the same type of PVC cement for both of them.
One of the other things that wasn't mentioned was the use of acrylic cement. A lot of that gets used for drainage plumbing. The application is pretty much the same, though.
You would think that melting plastic would take a little bit of time, but the one thing the article doesn't bring up is that, once you apply the solvent cement and connect the two pieces of pipe, they aren't coming apart again.
One time I was working on a project and accidentally put the wrong joint on the end of a piece of pipe. I realized it as soon as I did it, but I couldn't pull the joint back off. I ended up having to go back to the hardware store and buy a new section of pipe to replace the one I messed up.
I have used PVC pipe a lot. What I am curious about is, what are CPVC and ABS? Are they similar to PVC just with a different manufacturing process? Do you need special solvents for them?
I have used this stuff before, but I didn't have any idea what the real name of it was. I had always just heard it called plumber's glue or something along those lines.
The article isn't lying about the smell. It is really overpowering. The thing I really hate about using it is that most of the time when you are using the cement, you are in a confined space like under a sink or something, so it is really hard to get the ventilation that you need. Most people don't own any kind of respirator, either.
What I usually end up doing if I'm using the PVC cement stuff is just get one of the smaller desk fans and set it on the floor next to where I am working to try to keep the air circulating.
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