John -

First off, this is familiar turf.... Do an archive search or DAGS - this HAS
been done.

That being said, I don't think that PVC is going to work as your sanding
drum arbor. First, it isn't sturdy enough to give you a flat surface,
second, I'll bet it'd warp with the heat generated from the process. Third,
if you're surfacing a plane 22" wide you're either going to have 1) a rocket
as the work is grabbed and shot to the other side of the shop or 2) a rocket
as the material is kicked back against your soft, white underbelly. So,
unless you have some means of preventing kickback or have a power feeder
laying about, this is a very real safety concern...

If having to sand such a surface is a one time deal, or only rarely, you may
well just be better off taking the work to a cabinet shop and letting them
run it through THEIR drum sander. I guarantee you won't find a cheaper
method, and the results will be far better.

Barring that, this might be a good time for you to invest in a belt sander
and surfacing platen, and learn to use them.

I have a Delta DS, and love it, but trying to take off anything more than a
whisper of material at a time will make it stall out. I've don't know that
other small drum sanders are any different, it's just the nature of the
beast.

HTH,

John
"julvr" wrote in message
...
I am making a coffee table who's top is composed of small glued up
pieces of wood. Unfortunately, all the wood is slightly different
thicknesses (off by as much as 1/16 of an inch). I wanted a method
of ensuring that the final table top is perfectly smooth. I was
thinking of building a really big thickness sander.

The concept is to use a 22" piece of PVC piping, contact cement some
sand paper to it, and spin it exactly 3/4" above a surface, and pass
the pre-assembled top through it on a slight (15 degree) angle
through it.

Having never built a thickness sander before, I would like to hear any
suggestions anyone might have, or if anyone thinks this is a bad idea,
I'd like to hear that as well. (I'm a bit concerned that the heat
from the sanding might effect the pvc or contact cement for
example).

Thanks,

John