"Bruce L. Bergman" wrote in message
news
On Tue, 8 Apr 2008 09:12:25 +0800, "Den" wrote:

I'm machining some small enclosures using PVC electrical conduit (off
white
color). The electrical condut just happens to have the needed ID/OD. I'm
using acetone to remove the manufacturers ink labelling which is marked
down
the pipe, but the finish still looks like water pipe/conduit. I'm making
them in batches of 20 or so.

Painting or dying is not really an option, I could spin them in the lathe
and take a light cut along the length but I'd like to avoid this if I can.
I
thought about wiping over with solvent to soften and smooth the top
surface
but this may leave "wipe" marks on the surface.

I tried to source clean PVC pipe without marking etc but I could not find
anything.

If you call the pipe manufacturer and order in sufficient quantities
to make a special order economical to run, they'll make darned near
anything you want. Exact ID and OD specified (or even square or
rectangular) if you'll pay for a set of special extrusion dies, exact
color and type material you want, plasticizers for added flexibility,
markings or no markings, etc.

If it's being produced as water pipe or electrical conduit for
retail sale that pipe HAS to have the required markings on it by law.
They might be able to turn off the label printer and run you a special
batch, but that's about all they can change easily.

Does anyone have any other ideas on a quick simple way to finish the
external surface nicely?

Dip or spray with the right solvent. No touch, ergo no brush marks.

But be careful on solvent selection - on some plastics (acrylics are
most sensitive) certain mis-matching petroleum solvents will cause the
surface to craze over time with a network of deep cracks, that can
even lead to mechanical failure.

-- Bruce --



Thanks Bruce. My volume is so small that I'm not sure they'd even answer the
phone if I called.
The tubing is less than $10 a length off the shelf, the low cost is what
makes it attractive.

The solvent polishing is looking more attractive - especially if I don't
wipe it. Maybe MEK may be worth trying, its used with PVC so shouldn't have
any negative long term effects.