vacuum frame design

Hi:

I'm making a vacuum frame. I'm using a simple design consisting of a
piece of plywwood, pegboard, and clear mylar.

The plywood has a grid of grooves or channels routed into it that will
align with the holes in the pegboard. The pegboard will be glued on top
of the plywood. A hole is drilled through into the side of the plywood,
through one of the grooves, to make a "vacuum port". The mylar is placed
on top of the pegboard. The negative and paper are placed between the
mylar and pegboard

When a vacuum is applied to the hole it is supposed to suck down the
mylar and hold everything flat.

I'm concerned that I won't get even suction with just one hole. I could
put a hole on two or more sided and connect these with hose and or pipe.

Other people use frames similar to this. Do you get even suction - do you
need more than one spot to pull the vacuum from?

I'm about to glue the pegboard on. It would be easy to add another vacuum
port now, but next to impossible after the pegboard is glued on.

Any comments or suggestions?

Gord

---------------------------------------------------------
Gordon J. Holtslander Dept. of Biology
holtsg@duke.usask.ca 112 Science Place
http://duke.usask.ca/~holtsg University of Saskatchewan
Tel (306) 966-4433 Saskatoon, Saskatchewan
Fax (306) 966-4461 Canada S7N 5E2
---------------------------------------------------------
Received on Fri Feb 20 19:48:17 2004