Solid Surface Vacuum Table

[cweatherl]

I chose Corian because MDF Will leak vacuum like a sieve. Once the two Corian pieces are you epoxied together they will never leak air. I am using a Vacu-Press Vacuum pump which pulls 27" Mercury. This is equal to 13#psi. With the pods I get 130# of holding force and on a 15" X 5" piece I get 500#. This pump is designed to run all day unlike a shop-vac which will burn up after a few hours if it doesn't have enough airflow. If you haven't got a pump like that, here is a link to build one on your own. (http://joewoodworker.com/veneering/EVS/concept.htm) This pump looks like it is virtually the same as mine. Just a DIY version.
Here is how I made the table, as well as four vacuum pods.
The vacuum table and pucks are made from 12mm Corian solid surface countertop material. I milled 0.375" W by 0.1875" D channels into the inside face of each sheet, then epoxied them together. Being careful to overlap the beads of epoxy so as to make sure I got an airtight seal around the channels but not so close that I got epoxy in them via squeeze-out. After the epoxy cured, I cut the grid and holes through the top sheet at the end of each tube. The grid is made up of 0.652" squares & 0.375 channels (the channels are 0.1875" deep) this equals 1" from one grid square to the next which makes for easy set up. Also, it's easy to get 3/8" closed cell Backer Rod which is the foam I use in the channels to seal off the vacuum.
The pods are made in a similar way except I bored a hole through both sides so that the can adhere to the surface and the wood at the same time. I used these (http://www.m-powertools.com/products/va ... valves.htm) Vacuum Check Valves to temporarily seal off the face of the pods. These valves have a spring loaded ball bearing seated against the rim which (once epoxied in place) allows me to turn on the ball valve and then place them where I think they will work best on the machine. After I get them in place, I can place the wood on the pod and when I push in on the ball bearing it instantly pulls the piece tight via vacuum.

[txsteel]

cweatheri,

how is your vacuum board working out?

I am planning a very similar build, but with a standard vacuum pump.

[knowlzy0791]

I have issues with my Vac and there seems to be a lot of knowledge floating around this thread on how they work and how to increase suction force.

I don't mean to steal the thread, just hoping someone can turn my light bulb on up stairs for me

I have a 49" X 120" cutting area, currently run a "regen blower" I believe it is called (unknown to the strength of it) and use a spoil board which it pulls through. I cut UHMW from .125" up to 1" thick. Usually at around 300IPM (mass production so we need to run them quickly)

The current set up works for larger parts if I leave an "onion skin" of the material left so I don't actually break the suction chain. When I get down to smaller parts they tend to slide around and get chewed up. Especially if a chip makes its way under the poly.

Does anyone have any suggestions on a way to increase the suction of this table? I seem to lose more suction the further away I get from the vac which is where my main issue is, perhaps fluting the bottom of the spoil board down there to allow some suction from the front of the table to be distributed to the rear?