While dry-fit PVC pipe may work for a while, it does not hold up well to pressure and often retreats over time. For a more permanent solution, you should consider suitable glue or solvent cement specially formulated for PVC material.
By taping or gluing PVC pipes together, you can create stronger structures and solve plumbing problems. In this article, we explain the difference between simple bonding and more permanent bonding methods.
Read on to learn the most effective method for bonding PVC pipes.
Understanding PVC glue
It is important to understand that solvents for joining PVC pipes, such as PVC glue or PVC cement, differ from ordinary adhesives.
We normally think of glue as a means of accession two objects together. If you use regular glues like gorilla glue on PVC pipe, that’s what you get, but the bond isn’t strong enough to withstand time or pressure.
This can help if you want to hold two pieces of pipe together while you tend to do something else, but it’s not a long-term solution.
The PVC glue causes a chemical reaction that melts the surface of the pipe so the two pieces join together. They are no longer independent pipes, and any change to the joint requires cutting.
The process, cold welding, is strong enough to tackle more intensive tasks, such as domestic plumbing or creating weight-bearing structures.
Choosing a PVC solvent
Any regular glue should work for temporary grips or crafty construction (i.e. kids crafts), but try to choose something with a strong adhesion reputation for better results.
When choosing a solvent, be sure to choose one that works for your project conditions. Make sure you choose one specifically designed for PVC (Polyvinyl Chloride) and not ABS or CPVC. Each pipe material requires different bonding chemicals.
You should also choose an appropriate cement body for the size of your pipe. In general, larger pipes require thicker solvents. Check labels for solvent classification and check it for pressurized or non-pressurized projects.
The label also gives you ratings for certain conditions, such as:
- Temperature
- Moisture
- Pressure
Make sure they match the conditions of your application site, as well as whether the cement is approved for water systems or DWV (drainage, water and ventilation) systems.
Consider all other information on the label when making your decision. Different brands or compounds may have different application instructions and cure times, and one may work better for your project schedule.
Do you need a primer for PVC glue?
It’s best to err on the side of caution with primer. Most PVC glues explicitly require it, and it usually doesn’t hurt to use primer.
The PVC primer prepares the surface of the joint by cleaning it and improving the bond. Soften the PVC pipe to set the stage for cold welding, and the softer the pipe, the better the connection.
This sets it apart from PVC cleaner, which simply removes blocked substances. such as oil or grease, from the outside of PVC pipes. Although cleaner is better than nothing, it will not soften the pipe to improve the connection.
Most PVC primers are colored to give a visual perfection to their use. This not only reminds you of what you’ve already done, but makes it easier to check using a building inspector. It could be the difference between passing and failing an inspection.
If this isn’t something you need to worry about and you want a clean look, there are clear primers available.
Useful tools for bonding PVC pipes
In addition to PVC pipes, fittings and glue, it is recommended to have:
- 80-grit sandpaper and/or a box cutter (for burrs)
- A pipe cutter, handsaw, or reciprocating saw (for cutting the pipe)
- A pipe stand
- A marker (for marking the joints)
- A brush (for foundation if not included in the box)
Read the precautions and directions to determine which materials work best for you.
Safety measures when welding PVC pipes
Solvents for bonding PVC pipes are strong chemicals and emit strong fumes that can make you dizzy or disoriented. Even if you don’t notice an adverse reaction, these vapors are still there dangerous to your health.
It is important to work in an area with plenty of ventilation. Open a window if possible and consider wearing an approved vapor respirator while working.
Wear safety glasses, ideally those with side shields, to protect your soft membranes from emissions. Protective gloves help avoid skin contact that can lead to chemical burns, and you should address any splashes on the skin as soon as possible.
Protect your work surface with a tarp or towel to prevent damage and make cleaning up much more manageable when you’re done.
The best method for bonding PVC pipes
We will discuss the best method of gluing PVC pipes using a solvent binder. This differs from a simple glue swipe and involves:
- Gathering materials before starting
- Remove PVC from rough edges and burrs
- Dry installation of PVC pipe
- Prime the PVC pipe and secure it
- Allowing proper time for healing
The whole process takes about 3 hours, but this varies depending on your experience, the materials you have on hand, and the scope of your project.
1. Gather your materials
Make sure you have everything you need on hand before you start gluing anything. This includes:
- Your PVC pipe, cut to the proper lengths
- Fittings
- One level (depending on your project)
- Primer
- PVC solvent
- cloths (for quick cleaning)
Consider having a way to cut the pipe (i.e. a pipe cutter or handsaw) and sandpaper handy to make quick adjustments to your PVC project. We also recommend keeping extra pipes and fittings nearby so you don’t rush the shop if you make a mistake.
2. Remove burr PVC
A pipe cutter makes the cleanest cuts in PVC, while handsaws and jigsaws usually tear it up a bit. Stray PVC, burrs, can cause snags and clogs inside the pipe as it catches hair or other debris.
Burrs left on the outside of the pipe make it more difficult glue the corresponding PVCand you may find that the weld fails later, after you think you’re done.
You can cut the burrs using a cutter, but 80-grit sandpaper does a better job. Roll the sandpaper into a tube, then flatten it to fit the curve of the pipe.
Hold the paper at an angle to sand away burrs. Be sure to run it all the way around the inside and outside of the pipe, even if you don’t detect any burrs in those areas.
This sands the pipe and provides a clean surface for soldering.
3. Dry fit your PVC
Install dry pipe before applying solvent. This ensures:
- Everything fits correctly
- Everything is the right length
- You know what you’re doing before you run out of time
Use a torpedo level if necessary to ensure alignment. This is also the perfect time to number your pipes and fittings and make index marks Faster match.
Dry fitting is like a dress rehearsal for pipe fitting. You don’t want to make any mistakes at this point, but it’s better to do it now so you can fix it before you’re under more pressure.
4. Prime the pipe and fitting
Read the instructions on the primer for specific instructions. This usually involves wiping the primer on the inside of the fitting and the outside of the pipe, then letting it dry for exactly 10 seconds.
Immediately apply the solvent to the primed areas of your fitting and pipe, ensuring an even coat, then insert the pipe into the fitting.
Twist it gently, about a quarter turn, then press the pieces together and hold for about 15 seconds. This allows them enough time to set while preventing the pipe from pulling apart and creating a weak joint.
5. Allow time for healing
Most solvents cure in about 15 to 20 minutes before handling the pipes. It can also withstand water pressure, but it’s best to wait until it’s fully cured before putting the pipe back into service.
Most PVC should be ready to go in less than 24 hours after gluing.
Dealing with PVC bonding mistakes
Because the PVC glue changes the surface of the pipe, it is difficult to do correct any mistakes you make.
To correct the problems, you need to see the bad connection and use a coupler to bring the pieces together. You may need to use new parts, so it is recommended to keep a few spares on hand.
Follow the same instructions for the original joint and make sure not to repeat the original mistake.
Conclusion
Although you can use regular glue on PVC pipe, remember that it is not suitable for supporting weight or pressure. It is best to err on the side of caution and use a suitable solvent to join PVC pipes.
Remember to:
- Gather your materials beforehand
- Clean the pipe surface
- Use primer
- Hold the pieces together
- Allow ample curing time
Are you working on a project that requires bonding PVC? Comment with any questions you have!
