CPVC pipe is chlorinated polyvinylchloride. The controlled diameter is
the outside diameter. The outside diameter of PVC (polyvinylchloride)
pipe is also controlled, so the inside surface will be bumpy, lumpy
and uneven. So this is where problems may arise. The other plastic
piping mentioned in Mr. Kinsler's article have the inside diameter
controlled.
PVC gets its white color from the filler material mixed in the
resins -- it's plain old chalk. The temperature range of white PVC
is affected due to the amount of chalk in it. CPVC has more resin in
it than chalk and so makes for a better temperature range.
Another great source for all things plastic is United States Plastic in
northern Ohio: http://www.usplastic.com/catalog/default.asp From lab
ware to fiberglass, I-beams and floor grating, to pumps and duct work
(fume removal). Good prices; the more you buy the bigger the discount,
easy ordering and fast shipping.
There are other plastic tubing types that could work acrylic. Cast is
more expensive than extruded. Also, PVC pipe for electrical conduit is
a slightly different size and gray in color. There is a industrial PVC
pipe that has double the wall thickness and is also gray in color.
They also carry a clear PVC pipe and fittings for food grade plumbing.
The shining metallic coating on plastic pipe (and plastic in general)
is put on by vacuum deposition. Some pieces of whatever metal you want
deposited on the outside of the plastic are placed in a vacuum chamber
and heated to vaporization. At the end of the cycle the metal ends up
deposited on the plastic part. They do the same thing to apply chrome
on toy and model car parts.
If you are just making a small number of calliope pipes of varying
diameter you can wrap them in your choice of color pattern with vinyl
sign lettering material. It comes in rolls of various widths, 12 inches
to 60 inches, and rolls 10 yards or 50 yards long. You can get a
limited assortment of styles and colors from Dick Blick art supplies:
http://www.dickblick.com/
Or just take them to a quickie sticker sign shop and tell them what
you want.
Glen R. Perye Jr.
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