For those of you using shop vacs (any brand) to facilitate a vacuum clamping Table, What Vacuum are you using? Or even those of you who have recently purchased a shop vac as well. I know that several of my shopvacs cool the motor by the air being pulled through the hose and this type of shop vac will burn up if the airflow stops such as it does with a vacuum table. So the shop vac that is needed has to have another method for cooling the motor.
Recommendations will be appreciated.
I have my shop vac configured with a 2-1/2" port for vacuum table and 1-1/2" port for dust shoe thereby maintaining an air flow through shop vac. When vacuum table not used port is closed.
Have any pics of this set up? @CharlesPhelps
I am planning to build a vacuum table. Would love to see your set up. I am finalizing my plans now. I want to hold down 20x30 dollar tree foam to start with
Does the dust shoe not lessen the Vacuum portion?
What size vacuum table are you using?
The design I am working on is for an approximate 1500mm X 1500mm vacuum table. We want as much suction as we can get.
Typically I see shop vacs used for the down draft table, does anyone see or know of a reason not to just attach one of the cheap Harbor Freight Dust Collectors to the down draft table? Will this be sufficient for the vacuum force we are looking for? I know that shop vacs and dust collectors have different characteristics when it comes to their sucking powers but I would assume either would work. I see the industrial vacuum motors for professionally built CNCs and they seem to be oversized motors and blowers more similar to a Dust Collector than when compared to a shop vac.
I assume the motor itself cools on a DC rather than pulling air through the Fan itself. I just don’t know what effects stopping the airflow on the Ducting will have on the DC for an extended period of time.
I have been looking into and researching this issue for the past two years. I’m about ready to pull the plug and build mine now in a few months.
I would not use a shop vac for this, but it all depends on how serious you are about how your vacuum table will work.
Most professional set-ups use either a dedicated vacuum pump, or a vacuum venturi.
I am going to start with using the vacuum venturi system, as it seems the best way to go without buying an expensive professional vacuum pump. Here is one example of a vacuum venturi;
Pierson Workholding charges $500 for their vacuum venturi, but here is one that works the same for 1/10th the price;
Thanks.
This is for a buddy of mine. He is trying to keep costs down since it is a ground up build. His compressor is not sufficient for a Venturi system without burning it up.
A Venturi System is not very complicated, I would not pay $500 for one. There are better options in that price range and for a few dollars more. A person can build a Venturi with a few components from the local home center for under $25. I’ve seen designs on YouTube and the internet for home-made Systems that work just as well as the commercial Venturi units. The downfall to the Venturi is needing a more powerful air-compressor. The Venturi will drain the air quickly and an oil-less compressor will run continuously. Before I upgraded to my large shop compressor, my old oil-less C.H. Compressor was louder than all of my shop vacs and 5hp ClearView combined, it was the loudest Tool in my shop. I would hate to hear that thing screaming for 10 minutes straight let alone for several hours.
As a comparison for cost to build a Venturi, look at the Mist/Flood articulating lubricant units on amazon. They sell for $15. This is basically the exact same concept of a Venturi valve. Of course there are slight differences but same platform.
I use a Vac-U-Clamp Mark 6.0 Vacuum Generator in my shop. It works great! And I highly recommend it. However they don’t come cheap, but worth it for what I do/ want to do with it. My only concern is sucking dust into my Vacuum Generator, whereas this won’t be a concern with a shop vac or a DC.
Also check out this link.
I have even seen where people have recycled refrigerator vacuum pumps as well. I have not used one but I know it’s been done.
I even believe woodcraft sells a small pump for $150-$200 for Vacuum bagging and for blank stabilization for wood turning. I have not used this pump either but it’s possible that it would work.
Fyi Grizzly is selling most of their vacuum generators/Venturi Systems on Closeout discounted prices right now if you are interested in the Venturi System
Those are nice but they are twice the price as the VacuForce venturi with the same specs. Of course you need to add in the price of the compressor too 
How loud is that pump?
Michael couldn’t you put it in an enclosure with a HEPA inlet?
Would be very easy to make.
Make/model?
How loud is it Phil? I would look into buying a pump but most that I have seen are way too loud. Looking for 40Db or less.
Yes, my model was not cheap by any means. I saved up to purchase that specific model bc I wanted a plug and play especially after the first HVAC pump failed (entirely user error). When I get back to the shop, I will give you a decibel rating. It’s very tolerable though. A lot quieter than most compressors.
The air gets sucked in from the vacuum line and exits through the pump. So the filter has to be in the vacuum line itself before the line enters the pump. So a box will do no good.
Also. Harbor Freight sells vacuum pumps for the HVAC Systems. These typically have oil. They will spit oil all over the place if your not careful and if you run them low on oil, they will fill your shop with smoke if your not paying attention. This happened to me twice and with some good Walnut and oak ruined because of the oil, I decided to upgrade.
I also did not have the cheap harbor Freight unit. Mine was a $400-$500 Professional Unit. I don’t recommend the oil types used for HVAC unless you want to constantly pay attention to it and maintain it. I wanted a plug and play unit that I did not have to constantly work maintain.
I hung my Vacuum Generator in a storage closet and attached a remote switch to it. All I have to do is carry around the “Key-fab” remote and turn the pump on and off. No maintenance involved.
You get what you pay for.
Those are the best ones! They can usually suck an elephant through a straw.
