Introduction: PVC -- It's Great for Inventions
PVC, polyvinyl chloride, is a thermoplastic. It softens with heat and rigidifies when it cools again. While soft, it can be bent and even stretched into molds. Cold, it can be sawed, filed, drilled, scraped, or whittled with a knife.
PVC material can be found at most hardware stores in the form of plumbing pipe. I find it to be inexpensive, especially when I consider all the things that can be done with it -- musical instruments, repairs, tools and toys to name a few.
It is resistant to sunlight damage, has a degree of flexibility, is fairly strong, and is electrically non-conductive.
This is a very valuable material for use in inventions; one that very few people seem to be have experience with.
The picture below shows some of the shapes it is possible to make with PVC.
Step 1: Safety While Heating PVC
We love plastics for what they do for us, but plastic manufacture and decay tend to pollute the environment and negatively affect our health.
Vinyl Chloride, one of the components of PVC, is carcinogenic. When it is locked up in the polymer, however, it is much safer to be around. In my years of experience working with PVC, I have not noticed any adverse effects on my health from being around it.
Always work in areas with good ventilation. If you do get caught in a cloud of smoke, hold your breath and move to clean air.
When heating PVC with a gas stove or propane torch, try not to let it burn. Smoke from burning PVC is bad. With experience one burns it less and less. Don't panic the first time you do burn some. It scorches, but doesn't immediately burst into flame. Move the material away from the flame and try again. Don't breathe the smoke. Smoke avoidance comes naturally for most people.
While heating PVC over a gas flame, keep the plastic an appropriate distance from the flame to avoid scorching the surface before the inside can warm up. It takes time for heat to travel to the center of the material being heated.
Keep the plastic moving, and keep an eye on the state of the plastic. When heated, the PVC material is flexible, like leather. Beyond this stage, you risk scorching it.
A word from James, the plastic engineer -- "Just a word of warning, PVC can handle some high heats but if it catches fire, you wont be able to put it out, it does not need oxygen to burn so don't do this inside".
I do work inside, but my house is made of cement and has good ventilation. MAKE SURE THAT YOU HAVE GOOD VENTILATION. PLAY WITH FIRE -- CAREFULLY.
Step 2: Using Lacquer Thinner to Remove Lettering
Inventions look nicer without stray lettering on them.
When pipe leaves the factory, it is printed with information about the pipe. Fortunately, a little lacquer thinner and a piece of toilet paper will usually remove the lettering, or most of it.
Lacquer thinner vapors are not good to breathe. Make sure you have good ventilation. Only a small amount of thinner is needed to wet the wad of toilet paper. I poked a small hole in the plug under the cap when I bought the new can, instead of removing the whole plug. That way, I only get the thinner I need, and release the minimum amount of vapors into the air.
Step 3: Flattening PVC
To make a flat sheet of PVC to work with, cut a section of pipe and cut the pipe section down one side. Hold it with pliers and heat it over a gas stove.
When the plastic heats up, it will unroll itself and feel like a piece of leather. Place it on the floor and put a piece of plywood, or some other flat object on top of it until it cools. When it cools, it rigidifies again, and you have a flat sheet to work with.
Use a gas stove to heat large areas. Use a propane torch to heat small areas.
The photo below shows a narrow strip of pipe being flattened.
Step 4: Bending PVC
In the dust pan shown below, the square body was folded from a flat pattern.
The handle was formed by hand, pressing the heated plastic around a piece of pipe. Protect your hands from hot plastic by using rags.
To speed the hardening of hot plastic, you can cool it quickly with water. I sometimes hold projects under a faucet, use a spray bottle, or sponge them with a wet sponge.
Step 5: Using Molds
A mold is a shape that is used to create another shape. In the case of the toilet paper roll holder shown below, the hole at the end of the central pipe served as the "female" part of the mold. The ball of a ball peen hammer served as the "male" part of the mold. Between the two of them, they forced the flat plastic into a domed shape. When the PVC cooled, it hardened again.
The dome locks into the end of the pipe section upon which the roll of toilet paper spins.
Step 6: Example: Scissors Handles
Separate instructables could be done for each of the objects shown here. My goal here is to give you a broad overview of what you can do and to inspire you to invent whatever it is you need.
My fingers didn't fit in the handles of these tiny sewing scissors. I solved the problem by making larger handles and attaching them to the smaller handles. Just fold over the plastic and press hard until it cools.
Step 7: Example: Cup Holder
These are two cup holders mounted near my computer desk. It is nice to avoid spilling liquids onto the computer keyboard.
Step 8: Examples: in the Kitchen
PVC has solved a lot of problems for me in the kitchen. Move your cursor around the picture to get the details.
Step 9: Examples: Handles
PVC is smooth, and fits comfortably in the hand. It is great for making handles for things. Just heat the end of the pipe, jam it over what is left of the old handle and squeeze tightly until the plastic cools.
Step 10: Example: Fruit Pickers
A friend gave me a light weight fiberglass sailboat mast, which makes a great picking pole. I made an adapter for the end so I could use it with different fruit picker heads.
One has gardening shears mounted on the end. Pulling strings open and closes the jaws. I can cut small branches with it.
The other pole uses a two pole system to open and close a pair of scissors. I use it to snip the stems of fruit.
Step 11: Examples: Mixed
This is a collection of left over odds and ends.
I think that when the inventors in the Instructables community start playing with this material more there will be an explosion of new ideas.
"Necessity is the mother of invention." See what you need and try to make it.