New Plenum

[Gary Campbell]

As we move forward with the dual Z, our table layout had to be moved to allow both heads and drills to have full coverage of a 4 by 8 sheet area. This meant a total replacement of the existing plenum.

We decided to try Extira as a plenum medium. The 3/4" sheet of Extira was given a liberal coat of fiberglass resin on the back side, and then adhered to the PVC table board with a resin and West Systems High Density Filler mixture.

The plenum was cut .5" deep leaving 1.5" square blocks about 4.5" on center. Bit was 1.25 bowl bit with .25 radius, .25 stepdown, .75 stepover @ 3" per sec. Vac port holes were bevels with a 90 degree V bit .5 deep.

Plenum received 2 coats of resin after cutting, so its virtually saturated with glass.


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Gary

[wmcghee]

Hi Gary, how does this design compare to your old plenum. I'm about to cut mine and thought I might go with a design like this.
Do you still have T-tracks in your table?

[Gary Campbell]

Wayne...
IT seems to work better in all aspects but one. When the spoilboard gets down to 1/4" or less, it is spongy between blocks. This is not a problem, except with small parts when we dont pay attention to location.

Yes, we put the T track back, as it is an invaluable tool for holding both down and laterally. We did eliminate the center track along the X axis.

Gary

[wmcghee]

I think this is design I'm going to go with. This is my first vacuum table, I have used clamps and screws in the past. Thanks for the information.