Vacuums for a hold down table?

[Howley]

I have seen many suggestions to use the Fein vacuums (turbo 2 $475.00)for the hold own tables . Many use two of them.
However I'm not in a production environment , (well kinda).... Can't I just use an inexpensive Craftsman 5hp shop vacuum? I'm sure it would be noisier, but would it work? Couldn't I just build a sound proof box to dampin the noise?

I got the cut file for the plenum from SB, can anyone Direct me to the complete instruction set?

Thanks in advance!:D

[knight_toolworks]

it is much better buying the fein type motors and making a box. far cheaper and they work better. if you want quiet and don't use it for hours fein type motors are about 160 and run on 110. but going upto 220 they cost less and have more suction and air movement.
you can't use a cheap shopvac it will overheat fast and they are pretty loud.

[Brady Watson]

You will be disappointed with a regular ShopVac since they don't pull enough vacuum for CNC work. You'll get a much better bang for your buck using an Imperial brand vacuum from Ward @ Lighthouse.

Searchy
(http://www.talkshopbot.com/forum/search.php?searchid=1250637)
-B

[shilala]

I have a Festool CT33E that provides a bit more lift than a Fein and would do fine on a vacuum table. Plus it works with all their tools. It's just an option, and surely not a cheaper one. I believe the Feins are around 450 bucks and the Festool around 650.

The Festool filters down to 1 micron and works fabulously with sanding dust. Like the Fein, it's built for the duty a vacuum table requires.

To answer "could you?", you'd just need to check the cfm and lift of the Shop Vac that you're considering against the Fein or the Festool. I don't even know if they spec anywhere near the volume or vacuum you need.
A Shop Vac won't last long at all once you put it under this kind of load, even if it meets the specs. I have no idea how many hours you plan to put on the Shop Vac, but you won't get many hours of continuous duty.
Lowes always sells big ones cheap at Christmas-time. You could always check the specs and give it a go. You'll only be out 40 bucks or so. Maybe it'll last enough to meet your needs?

[curtiss]

I went to a local vacuum repair shop and they had a bunch of old vac motors of all sizes.

Bought a used carwash vacuum motor with new brushes for $30.

[Brady Watson]

Shopvacs usually pull a max of 4-5 Hg" and that's about it. A Fein pulls 7.3 Hg" max/126 CFM. Festool 7.0 Hg" max/137 CFM. Those extra 2 Hg" make a difference.

If you want to save money AND have more performance than any ShopVac (incl. Fein/Stool etc) for around $100 or so, search this board or click on the link I provided for you above. All the hard work has been done for you already...

-B

[kenkelsey]

Hi Brady. I'm not too good finding my way around the forum, but I see many references to your vacuum hold down solutions - Brady Vac 2. I can't find it. I want to build an inexpensive vacuum hold down for by 4 by 8 alpha. I have the plans for the plenum and the piping, but I don't have a good vacuum motor. Fein too expensive for me. I see Lighthouse referenced, but need a little help. Can you direct me to one of your posts to build your own vac hold down. Thanks Ken

[David Iannone]

Ken,
See this link for Brady Vac 2

http://www.shopbotblog.com/index.php/2007/07/the-bradyvac-ii-–-a-production-vacuum-fixture-on-a-shoestring-budget/

Dave

[David Iannone]

And this:

http://www.centralvacuummotor.com/shopbot.htm

[Roy Harding]

I built a small (24" X 18") vacuum table for my desktop, which used a shopvac as the vacuum source.

It worked well, BUT - I burned out the shopvac in short order. Subsequent research (which I should have done beforehand) revealed that most vacuums use the incoming air flow to cool the motor. Cut off that airfow (as you do when using it for a vacuum table) and the motor has no way to cool - and burns up.

There are industrial vacuums which use a separate airflow for cooling (whether Fein is one of these or not, I don't know) but they are quite expensive.

I'm going to be reprising my vacuum table in the new year, but this time will be using a venturi driven vacuum clamp set up I built from plans available from joewoodworker.

Of course, I'm dealing with a very small table - not an industrial sized one.

[gbradley]

What do you plan on cutting??

[kenkelsey]

Thanks for the links. I have ordered the Lighthouse Vac motors, now I'm looking into the enclosure to house the vacs. What Gary Campbell has designed seems complex.