You'd have to be a seasoned electrician or PVC afficionado to bend even close to the amount of PVC that I do here at the shop. I'm not trying to brag, I'm just trying to share a few tricks that I've picked up along the way. I'd say there are ten things you need to know to become a PVC bending master, and I'd say it's high time that you knew. Most top ten lists start at ten and count down, but there's no punch line here, so here they are, starting at number one:
1)Put the freakin' heat gun down already, and go get a PVC Bendit.
Really, I mean it. Every existing method of bending PVC pipe is really an improvisation, with the exception of the PVC Bendit. We studied PVC like anthropologists studying some ancient tribe. The difference is, PVC just happens to be the most studied, most documented building material on the planet. We found out what the exact temperatures are, and we tuned this tool precisely to reach those optimal temperatures in a reasonable amount of time. The PVC Bendit is not so hot that it's going to scorch the pipe instantly, but it's not so cool that it takes forever. It is the perfect temperature to allow you to heat PVC pipe for bending withough neglecting your other duties on the project. To say it straight, PVC Bendit is the only tool that was actually designed specifically for bending PVC. All other tools are repurposed existing tools that just happen to do an OK job.2
)Turn it, or you'll burn it.
If you think you can just apply heat to one side of the pipe until the entire thing softens, you've got another thing coming. Try putting a hamburger on your grill and cooking it to perfection without flipping it. You're going to have one nasty burger. I don't care how you're making your bends, if you don't move the heat source around the pipe, you're going to have some problems. With the PVC Bendit, you only have to turn the pipe about once a minute, but seriously, do it. It's worth it. Once you get the hang of it, it'll be completely automatic for you to do it, and you will produce perfect bends no matter how complex they are.
3)Plan your work before you start.
Unless you're working on an abstract art project, you should have a very clear idea of just what you're trying to do. If you're bending PVC electrical conduit into a compound offset, know your dimensions and exactly what you expect to create before you start. If you have a solid picture in your mind of what the outcome will be, your expectations will shape your actions, and in turn, you will get exactly what you set yourself up to make. On the other hand, if you just heat up the pipe with a vague idea of what you're going to do with it, you're going to be holding something that's like a cooked spaghetti noodle and wondering what the hell you're going to do with it. The better the plan, the better the product, no matter what you're doing.
4)Use forms or jigs for everything.
If you know you're going to need more than one part, this is extremely important, but even if you only need one, the form/jig will ensure you make exactly what you're trying to make. Whether it's the Build-A-Bend or a freakin coffee can, a form will save the day. I don't mean to say that you need a super specialized forming system for every bend - it's far from that, actually. Keep in mind that even the area you're trying to do the offset in can work as a form. Anything that matches the shape you're trying to make will work, but seriously, the best results will always come out of a well thought out form.
5)If you're bending a large diameter pipe to a tight angle, use internal support.
If you're bending four-inch PVC pipe into an arc that has a 36-inch radius, you're going to need to stick something inside of the pipe to keep the wall from collapsing. Really, every pipe over about 1 inch in diameter can collapse when you bend it. Even the little ones can if you go tight enough, but the big ones tend to collapse just under their own weight once you put even a small bend in them. What I recommend is that you get an extra sleeve that you use exclusively as an internal support sleeve when you're actually making your bend. If the curve is super tight, you drop in the bending sleeve, bend to the desired position and hold it for a minute to allow any stretching and compression to happen. Then relax the pipe, pull the sleeve out and return it to the desired bend position. Because the stretching and compresstion have already happened, the pipe will gladly accept its new shape with no collapsing or kinking whatsoever. There's a lot of talk about sand and air pressure out there: Don't listen to it. It's a pain in the ass. Just get an extra sleeve, and it is MUCH easier.
6)If you're bending a larger diameter of pipe than your PVC Bendit, sleeve it up.
While the PVC Bendit will definitely heat up larger diameters of PVC pipe than its own diameter, sleeving up will dramatically improve you heating times. For example, a Series A bender will bend up to 1 1/4" pipe with no problems no matter what, once you get past the 1 inch point, it works a lot better to sleeve it up. Without the sleeve, a Series A bender might take up to ten minutes to sufficiently heat a 1 1/4" PVC pipe up for bending. With the sleeve, the same bender will have one and a quarter inch pipe ready in five minutes or less. You can't beat that, and it is really simple to do. The way it works is like this: metal is much more conductive than air. If your sleeve is around the bender, it will get very close to the heat of the bender, and it will bring that heat much closer to the pipe wall.
7)Use the BendStation.
We don't send that thing to you because it looks cool, and we don't send it to you as packing material for the box. We send it to you because it make the whole process faster and safer. Whatever your ambient temperature is in you work environment, it's not hot enough to bend PVC. That's why you need a tool to heat it up for bending in the first place. The BendStation is as much a part of the PVC Bendit system as the actual PVC Bendit. It keeps the temperature in your work area from interfering with the temperatures that are required to do your work. That means that it makes the whole process a lot faster. On top of that, the pipe gets really hot. The temperature range for bending PVC is between 170 degrees and 220 degrees, with 170 being perfect for long, sweeping arcs and 220 allowing you to make tight curves. That's hot enough to burn you, and all you have to do to keep that contained is keep the whole process inside of the BendStation.
8)Wear gloves when handling the bender and hot pipes.
PVC pipe is extremely hot at bending temperatures, but it's a weird kind of hot. If you've got working hands, it really won't cause you much immediate pain. What happens, though, is that the heat creeps through your upper layers of skin and burns the tissues beneath it. This is even more true if you've got callouses on your hands. They act as great insulators, but once the callous itself gets hot, it holds the heat in and continues to burn your subcutaneous tissue even after you've set the pipe down. I'm telling you this because it's happened to me, and I really don't want it to happen to anyone else. You should never touch the hot zone of the bender with your hands. Even gloves are no match for the heat of the actual bender body. Just be careful, wear your gloves, and either use the hot tool or a pair of pliers if you need to touch the hot zone for any reason.
9)Stay close to the bender while it's on.
Don't wander too far away from the bender if you've got a pipe on it. It goes back to the hamburger principle. If you drop some burgers on the grill, go pee, get a drink, check your e-mail, and then get pulled into a facebook conversation, you're going to come back to some messed up burgers. In that same way, if you've got a pipe on the bender and you get distracted, you're going to come back to a mess. I've left pipes on the bender and then gone to lunch, and when I got back, the pipes were completely melted onto the bender, truning brown, and letting off some really nasty smoke. Not good. We don't know everything that's in that smoke, but some of the things we do know of are reasons enough to keep an eye on the process the whole time it's going.
Even if you bend PVC pipe every day on the job, enjoy yourself. Remember, 99 out of 100 people don't even know that if you heat a PVC pipe up, you can bend it. You're doing something cool every time you make a bend, and it helps to remember that as you're working. If this is your job, you've got a cool one. One day, if you find yourself like, "This f*%&ing piece of s#!*!" remember that the guy making burritos at Taco Bell would think that what you're doing is really, really cool. Even if you're focused on an extremely technical task, pretend you're screwing around with a cool process, and you'll feel good about what you're doing.