Another Vac Table Setup

[Gary Campbell]

Hey guys.. I now have enough testing done on the "Plastic Prototype" vac table to put forward some numbers for anyone that may be interested. Table is 2 layers of solid PVC type 1 gray (5 x 10 sheets) roughed up and epoxied together. Plenum is a 4 X 8 sheet of the same but cut into 4 (2x4) quadrants to cut down on the milling for the 8020 T track. 4 vac motors are Grainger 220V 111 cfm/95.2" H2O direct mounted with Allstar gasket to the bottom of the table. Plenum is cut with 3/8" ballnose 5/16" deep to accept AllStar XC 375 round if I need to make a plenum smaller for any reason. I also used their IE 2525 for a perimeter seal to the spoilboard. Each zone is switched & has a vac gauge. Electricity is much easier for me to work with than plumbing. And no leaks! Numbers are: Zone with approx 1 sqft gasketed off ....7" Hg Zone with 1/2" UL mdf spoilboard....1.5"Hg Cutting Operations with a lay on plexi or 1/4 ply mask 5.5 -6" Hg. 400 cfm+/- (in theory),6" Hg,4 zones and around 600 for the vacs, wiring and gauge plumbing. My sincere thanks to Robert Ball, David Buchsbaum and Brady for the information and inspiration.
Gary
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[Brady Watson]

Super-clean install! Great job!

-B

[evan]

SWEET! Looks like you've got all your hold down needs met.

[Gary Campbell]

Evan,
I don't know if all my needs are met, but the method that uses hi volume, low vac for larger pieces works well. I now am working to get pallets built to drop in the table in place of the spoilboards. I will be experimenting with about 4 or 5 of AllStars gaskets along with neoprene and silicone O-rings. I am also about half done on a bolt down vac clamp for longer boards and moldings using 2 layers of PVC with vac channels routed between them. There will be 2 pucks per valve and one of them will have a Mach ball valve installed. Waiting on the valves from joewoodworker(dot)com to finish the matrix. Heres a couple pics of progress.
Gary

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[evan]

I like the "long board" holder. I just finished a job cutting the mortises in solid walnut styles for 12 louvered doors, where it would have come in handy. Instead I had to create a jig to hold them in pairs.
One question: does the hi volume, low vac area extend across the full 5' width? If not would it be difficult to put another zone under that 1'x 10' section? You never know when you might want to cut a full 5 x 10 sheet of material.
As was said already your work looks great.
Bot on!

[Gary Campbell]

Evan,
At present it does not. 2 reasons... I was able to save a bunch of $ by buying a 4x8 for the plenum, and I dont foresee a need to handle sheets over 4' wide. But I am sure the Baltic Birch Bunch will disagree. It would not be difficult to do, either by redesign of the 4 zone system or adding a 5th zone. Thanks, Gary

[jhicks]

Looks very nice Gary, Our grid and general systems on plenum style in zones look very similar. Just one question, what do you use the T Track for? In our case spoil board(s) mount over plenums and hold themselves in place so just curious.

[Gary Campbell]

Jerry..
The T-Track can be used for hold down by either inserting carriage bolts for David B's Cams or dropping in weld nuts and using nylon bolts if close to the bit. They also divide off the table letting me use smaller replaceble spoil boards or a special use pallet that can be bolted, held with vacuum, or just set in place. As a newbie, I am trying to be as flexible with the design as I can, without using any wood products in the table. Since the track is 1/4" higher than the plenum, bit shear is virtually eliminated against the pallet. All my zones are exactly the same size, so I can be setting up a zone while another is cutting.
Gary

[mthomas]

Gary,

Can you make any comment on the relative noise level of vac motors, either individually or in banks? Are the single motors more/less than a Fein or typical ShopVac? I know it's all subjective, but your opinion would be welcome.

Thanks,
mt

[harryball]

Speaking of noise, I found a way to make my 2 feins even quieter... I installed two 3" exhaust ports to feed my hoses through and moved them outside. The noise and heat are now outside while I'm in the shop nice and cool listening to the radio.

I had a 4 head vac table similar to what Gary pictured using shopvac heads. It did work well but I never figured out how to quiet them down and keep them cool at the same time.

Robert

[Gary Campbell]

Michael..
The Vac motors left open as they are shown are somewhat noisy as Robert says. And , of course, the more that are running, the noisier they are. The noise, combined with that of the 1.5 HP Delta cannister Dust Collector, still is not as loud as the bit when cutting some materials, though. One of the 1st things told to us at SB training was eye & ear protection. I have a shop with 3 separate dust collectors, shapers, planers, sanders a dozen routers... etc.. all are noisy and ear protection is a MUST! My plan is to make the system work well first, then see what I can do to quiet them down. The motors I used are a 2 stage with metal impellers.. the euro 240v version Fein replacement that has a separate cooling fan for the motor, so heat doesnt seem to be a problem. Even when I notched a 5 gal bucket and slipped it over the motor to see what effect that had. If noise is an issue for you...then you might want to plan otherwise as I havnt even thought about mufflers yet.
Gary

[mthomas]

Great info and thanks alot. The noise is one of the reasons that I'd considered a tangential vac instead of the axial like you used. I figured with the tangential layout I would have more options for potentially ducting the heat/noise externally or into a muffled chamber.

I know that folks who have designed and built cyclone collectors have used simple, low-cost tractor mufflers for waste air with suprisingly good results.

[Gary Campbell]

Michael..
I lost the 2nd half of your question.. I cant tell if its more noise or $ you question. Noise...more than a Fein about the same as a shopvac....EACH
Price was $115 +tx &shp So less each on the price. Hope that was the answer you were looking for.
Gary

[mthomas]

yes it was and thanks again. i was particularly interested in noise compared to a fein or shopvac.