Instructables
Picture of Shaping Small Parts from PVC
With a Pyrex measuring cup, a little water, a piece of PVC, and a microwave you can shape plastic pieces that enable you to do and make useful things.

WARNING: Our PYREX cups are several decades old and work well with high heat.  I just learned PYREX was sold to a company off-shore that uses a different composition for the glass, and it is prone to exploding violently under heat stresses that were no problem for the original PYREX.  It sometimes explodes as you are removing it from an oven.  (October 12, 2009)

 
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Step 1: From round to flat

Picture of From round to flat
Pictured is a half-round piece of PVC I had left over from another project. The flat square was made by cutting a piece from the half-round and heating it while the water in the Pyrex cup boiled in the microwave for two to three minutes. I removed the cup from the microwave and used the tongs to pull the PVC piece from the very hot water. The tongs also helped to unroll the softened PVC so I could place the piece of wood over it and hold it flat against the countertop until cooled and firm. In the absence of a good supply of Plexiglass, some PVC flattened with the aid of a microwave and some hot water offers some impromptu versatility.
juiceman742 years ago
Phil, Thank you so much for the interesting post (as usual).

Can you first expand the idea behind the Dremel holder?
I'm looking into creating my own Dremel press. Would you recommend any technique?

Also, I was just wondering, about the GPS ball; Wouldn't it make more sense to form a mold from the original, and then cast a new shape from that?

Keep it up,
God bless - O>
Phil B (author)  juiceman747 months ago

I am sorry. I missed your comment until now. When Instructables began lumping more than one comment into one e-mail notification, I began to miss comments below the bottom edge of the screen.

I never did make a Dremel holder. The idea was a mount for the Dremel that worked like a stand. In this case the mount would be able to swing in an arc around the ball I was making to make the ball perfectly round. My idea was a form fitted clamshell held together with screws to clamp the Dremel into place.

Taking a mold of the ball and casting it would be a possibility. A video came to mind of a wood lathe setup for making croquet balls. There was a curved metal ring around the blank for the ball. The chisel was mounted on the ring and could move around in an arc to form the wooden blank into a perfect ball.

diykiwibloke7 months ago

Hi Phil,

Thanks for your ible. Can you please tell me what I could use to glue small curved pieces of PVC to the inside of a PVC pipe? I'm building a workbench portable LED light. The LED strip is mounted on the flat part of a round (ex computer) CPU heat sink that has a small fan inside it. The diameter of the round heat sink is slightly too small for the pipe.

I want to cut some small curved pieces of a slightly thicker pipe that should work as packing to take up the slack between the pipe and heatsink.

My question is: with what can I glue the PVC pieces to the inside of the body of the PVC pipe?

Thanks for your help.

John

Phil B (author)  diykiwibloke7 months ago
John,

What comes to mind immediately is the cleaner and glue used on PVC by plumbers. It is quite effective. But, it is also costly to buy small cans for just one little thing. If you have a friend who uses it regularly, you could "borrow" his cans of cleaner and glue. Otherwise, I would rough up the surfaces with coarse sandpaper and use a good epoxy. It should work well enough. Sometimes I use not glue to make rivets. I would drill a couple of holes through the two pieces of PVC with a little taper toward the outer surfaces and fill each hole with hot glue from both sides. When cooled it acts like a rivet.
Phil B (author)  Phil B7 months ago

I meant "hot" glue rather than "not" glue. The auto correct on my iPad thinks it is smarter than a human. Most of the time it saves me from mistakes. Sometimes it creates its own mistakes.

Thanks Phil - great to get your input. I really enjoyed your superbly right-brained hot glue 'rivet'

Phil B (author)  diykiwibloke7 months ago

Thanks. I have used hot glue rivets a couple of times and they have always worked well. The idea sounds a little low class, but has several advantages when that is what you need.

b1u3f0x4 years ago
You do understand PVC has lead in it right?
Phil B (author)  b1u3f0x4 years ago
I was not. Since you mentioned it, I see lead is used to stabilize PVC. I could not find anything about conditions under which lead in PVC might be released. Some items noted we use PVC for lines carrying drinking water, but seemed to let it drop there. What do you know for certain?
Actually, PVC is typically only used to carry waste water *out* of the home (ABS is only used for this purpose too). Any lines that carry potable water will be made of copper (unless the plumbing is very old, in which case galvanized steel used to be used a long time ago). For lines that carry drinking water into appliances (like to feed your ice maker), those will be made of PEX (cross-linked polyethylene). Cool tip though... I'm going to try this out (using an old pan filled with water).
I live out of town and we have our own well, it is newer and every drop of water in our house passes through PVC from the well to our blast tanks.
Your summation of residential piping is not entirely accurate. PVC piping is routinely used for carrying potable water as well as DWV piping; the latter is typically "Schedule 40" piping. PEX tubing is also used for potable water, heating systems, and - thanks to its flexibilty - in under-floor radiant heat sytems (Which ROCK!). Older homes also used copper supply (usually with lead solder) and cast iron for DWV. REALLY older homes used cast iron for everything, some used lead for DWV.
MaddMann Phil B3 years ago
Newer PVC (Poly Vinyl Chloride) is lead free, look for ROHS compliant materials. Typically PVC is only harmful if it burns up. Warming it, as you did, in water shouldn't cause any harmful vapors or smoke which is where the real danger is. Lead free or not, PVC smoke is very harmful! I have spent the past 30 years working in environments where PVC is heated to melting point and extruded into various shapes. Don't take my word though, do some research on ROHS compliance, and MSDS sheets for various types of PVC from manufacturers of it.

Be safe, and keep the nice instructables coming!
Phil B (author)  MaddMann3 years ago
Thank you.
Goodluck4 years ago
Another wonderful tip. I'm not yet sure what I'll use this for, but I'm sure I'll use it.

By the way, I'm sure you're familiar with the "burrs" that saw cutting pvc leaves behind. An excellent way to get rid of those is a rag dipped in acetone (finger nail polish remover). They wipe right off.
Phil B (author)  Goodluck4 years ago
Thanks.  I usually removed the burrs with a file or sandpaper.  I will have to try acetone.
covey124 years ago
yea, burning pvc emits a harmful gasses, not sure about melting itthough
Seppuko5 years ago
Phil, This is a great Instructable. I stumbled upon it for other reasons, but it suits the needs of a different project I had in mind but hadn't figured out how to do. Thanks for posting it. Out of curiosity, why do you microwave instead of using a pot of boiling water?
Phil B (author)  Seppuko5 years ago
Thanks. I am glad it is useful. The microwave was more a matter of personal preference. I felt I would not need to wait so long for the water to reach a boil and I would not need to wrestle a hot metal pot. Since doing this I came into some birthday money that I spent on a heat gun, like a big hair dryer. It makes shaping PVC even easier.
northie5 years ago
Not to be a devil's advocate but, isn't there a chemical in PVC that you would be exposing yourself to if you heat it?
Phil B (author)  northie5 years ago
I did not notice any vapors or smells when heating the PVC with hot water. If I thought that is a problem, I would be sure to work in a well-ventilated area. I have a stick welder and there are noxious fumes. I try not to weld in closed areas and try not to breathe the fumes.
northie Phil B5 years ago
Just be careful. You get mixed stories online. Some say it's safe, others say heavy metals leach out when heated and the vapors are have been linked to lung cancer. It might not be from being heated underwater though.
ycc21065 years ago
Great tip! I'll definitely use it. Thanks!
Phil B (author)  ycc21065 years ago
Thanks for your comment. With a little imagination you will find even better ways to make use of it.
Davetech5 years ago
This will similarly work with ABS black plastic pipe, although I heat it up in a toaster oven. I keep a close eye on it and check the material's temperature often with my infrared thermometer. It seems that 260 degrees F is when the ABS goes soft and pliable.
The 4" ABS pipe I used has 1/4" thick walls, so if you flatten it, you will have a very sturdy, weatherproof platform to mount projects on or whatever. Gorilla glue does a good job of joining ABS pieces but I have not tried it on PVC. It seems like PVC cement would do a good job in joining the squares to create your sphere.
Phil B (author)  Davetech5 years ago
Thanks. See my response to colinlewis. I do not buy PVC cement unless I have a job that very much requires it. The stuff always turns to sludge before I can use much of even the smallest can of it.
Phil B (author)  Davetech5 years ago
ABS would work. I have not tried it.
colinlewis5 years ago
Very useful technique with some practical applications. I have used PVC in a variety of uses, but never heat formed it. Regarding the epoxy, I would bet that a thin layer of the glue used to connect PVC pipe to its fittings would work well, I believe it dissolves part of the PVC itself forming a strong connection between the two pieces.
Phil B (author)  colinlewis5 years ago
I think you are correct about the real PVC glue holding better through dissolving the surfaces together. I have some of the PVC cleaner solution, but the glue always dries out before I can use much of it. I no longer have the glue and this job was too small to run out and buy another can. I also should have waited longer for the epoxy to cure before messing around with the pieces. But, the threads I cut are holding very, very well. PVC is easy to form and heating it with water is almost foolproof. Thanks for your comment.
Phil B (author) 5 years ago
Thanks. Rimar. I hope you can use it.
rimar20005 years ago
Great, Phil!