1" PVC for vacuum plenum

[ddgman2001]

Does anyone have experience using 1" PVC sheet stock for a vacuum plenum?

I'd like to try using it to make a master vacuum bed with 1/4-20 threaded inserts and dowel pins for locating and bolting jigs.

I'm just concerned with the wearability.

[Geof]

PVC is not good with much tensile stress and it tends to creep.

[ddgman2001]

I didn't know about the creep. Any suggestions for an alternate material? I haven't priced out cast alu, but I doubt my budget could handle it.

[Geof]

You do not mention any sizes or what type of work will be done. MDF or plywood could be possibilities but not if you are using coolant. Aluminum is probably the best for ease of making it, strength and lightweight but it would be expensive for a large plenum.

[ddgman2001]

I was originally thinking of covering my 48" x 48" table, but I think I'll scale down the plenum size to 40" x 20" which is doable cash-wise using 5/8" thick cast aluminum. That will cover 90% of my needs.

[oldhack]

Originally Posted by ddgman2001 I was originally thinking of covering my 48" x 48" table, but I think I'll scale down the plenum size to 40" x 20" which is doable cash-wise using 5/8" thick cast aluminum. That will cover 90% of my needs.

Poly is probably cheaper than aluminum. I was thinking of using it on my build.