Vacuum pressing - sufficient clamping pressure?

"Jay Pique" wrote:

> I'm wondering if I can use vacuum clamping to glue up table legs.
> I'd
> like to laminate 3 pieces of hard maple that are ~1x3x36" and I need
> to make up around 50 of them. Provided the material is flat and
> well
> surfaced, will atmospheric pressure provide sufficient clamping
> pressure for a nearly invisible glue line? Or am I better off
> throwing them in the clamp rack? Probably the latter, I'd guess,
> but
> I'm not totally confident of my understanding of atmospheric
> pressure. It's 1774 per square foot, right? I can easily get more
> than that with bar clamps. Maybe I answered my own question.

It is a matter of resources.

How many clamps do you have?

How much space can you dedicate for a glue up to cure either in clamps
or in a vacuum bag(s).

You could probably glue up 4 legs at a pop in a vacuum bag; however,
you will have to leave the bag in place until the glue cures.

When working with a vacuum bag, you are dealing with atmospheric
pressure which is 14.7 Pounds per Square Inch at sea level.

That's more than enough pressure to collapse most buildings so no need
to sweat some leg glue ups.

You will get better uniformity of clamping pressure with a vacuum bag
than you will with clamps; however, either will work.

Have fun.

Lew