WILL A SHOP VAC WORK AS A DUST COLLECTOR??

CFM vs. Static Pressure, defined
Air volume is measured in cubic feet per minute (CFM) or liter per second (l/s)--the volume of air that the device can move from its intake to its exhaust in a given amount of time.

Static pressure is measured in inches of water (often referred to as inches water column, or inches WC), as in, how many inches the suction device can lift water up a pipe, or in millibar (mbar).

In simple terms, static pressure determines how much resistance (“static pressure loss”) your dust collector can overcome in order to move a given volume of air through the hoses and pipes. When it comes to designing a dust collection system, the raw CFM figure is initially more important than the raw static pressure figure, though static pressure does come into play once you start designing your ductwork (more on this later).

Is that enough CFM and static pressure?
WOOD Magazine has a great article on calculating CFM and static pressure requirements for dust collection. Although the worksheets in the article may look intimidating at first glance, they aren't too difficult to fill out. The article includes some typical CFM requirements for various tools, some of which I've included or summarized below.

Table saw, radial arm saw, miter saw, bandsaw: 350 CFM, 165 l/s
Belt, disc, or drum sander: 350-550 CFM, 165-260 l/s (depending on size)
Table-mounted router: 195 CFM, 92 l/s
Thickness planer, up to 13": 400 CFM, 190 l/s
Thickness planer, 14"-20": 785 CFM, 370 l/s
Now let's look at some contenders for an entry-level dust collection system. As of this writing, a ”6.5 peak horsepower” Shop-Vac® vacuum rated at 9.3A@120V produces 185 CFM (87 l/s) of airflow and 64 inches (160 mbar) of pressure. That's not even adequate for the least-demanding machine in the list, falling 10 CFM (5 l/s) short for a router table. In practical terms, this means the vacuum won't be able to produce the recommended 4000 FPM (feet per minute)/2 m/s (meters per second) linear air velocity necessary to capture most of the dust particles produced by the tool. (Note that the 4000 FPM/2 m/s figure somewhat oversimplifies things but it is a good, convenient figure for making realistic estimates.)

By comparison, a 1hp Grizzly dust collector rated at 8A@110V produces 500 CFM/235 l/s and 2.76"/7 mbar of static pressure. As you can see from the CFM figures above, under ideal conditions this dust collector should be able to capture most of the dust from most tools except larger sanders and 14" or larger planers.

Remember, I said that was under ideal conditions. This is where static pressure comes into play. Every inch of pipe or hose, every turn, and every change in diameter produces resistance which your dust collector (or vacuum) must overcome. You can use one of the various static pressure calculators such as Bill Pentz's static pressure Excel spreadsheet to calculate the static pressure drop produced by your ductwork and hoses. For the Grizzly 1hp dust collector we looked at earlier, the total static pressure drop can be no more than 2.76"/7 mbar. If you plug only 500 CFM/235 l/s and 7 feet (2 m) of 4" (10 cm) flex hose into the calculator, you'll see the static pressure drop is almost 3"/7.5 mbar, so we already need to look at a more powerful dust collector.

Although this is the simplest way to size a dust collector, you don't suddenly go from 500 CFM to 0 CFM. The excessive static pressure loss simply reduces the airflow through the system. Some manufacturers or magazines provide the CFM curves at various static pressures, which is helpful in determining whether you can sacrifice a few CFM for a longer run of pipe or hose while maintaining the recommended 4000 FPM air velocity.

Other considerations
In addition to the fact that a Shop-Vac just isn't suitable for stationary power tools, one of the dust collector's greatest advantages over a Shop-Vac is that it has a larger hose and is less likely to clog from chips and shavings. Whereas a Shop-Vac typically has a maximum hose size of around 2-1/2 inches/6 cm, a dust collector hose (or pipe) is typically 4 inches/10 cm or larger and is less likely to clog.

Getting back to your questions, you asked whether a dust collector can (1) pick up or (2) filter things that a shop-vac can't. We've already answered the first question (yes, a dust collector can “pick up” more). HEPA-rated filters can remove 99.97% of particles down to 0.3 microns. You can buy these types of filters for both Shop-Vacs and dust collectors, so technically the answer to the second question is yes but it just depends on what type of filter you buy (and, in some cases, how determined you are to adapt such a filter to your machine if your manufacturer doesn't offer one).

Of course, even the best dust collector will not capture all the dust, and even if you pony up the cash for a HEPA filter your dust collector will disperse some amount of fine dust back into the air. That is why you should try to exhaust your dust collector outside if it is practical (while also venting outside air back into the shop), and you should still wear a well-fitted respirator with replaceable P100 (HEPA-equivalent) filter, regardless of any other precautions.

If you want, you can learn how to do it with Stodoys woodworking plans.

shop vac is like Band aid lol and a few others i cant think of at the moment

Hola Alex, great job dude!!!
Quick question 🙋🏻‍♂️: how much dust you get on the vacuum ?
I made a custom cyclone and I have problems with the very fine dust (when I use the orbital sander).
Do you have the same problem with this dust deputy ?
Thanks in advance.

I've been running my shop dust collection system off an old Dyson upright I found on the side of the road for free and a dust deputy on a 40 gallon drum for years.

It works amazing. Debris has never made it as far as the Dyson to need cleaning. Everything ends up in the drum.

Just 1 question, how much HP does your shop vac has?

Honestly didn't have much faith in the shop vac setup, you have changed my mind on that thanks for the content 👍

get to the point please

Very interesting and unique, thank you! Did you hook up the planer yet, and how did connecting the 4" to 21/2" go? Also, how much of this was passing through to the shop vac? Also, thoughts on static buildup? I see see some buildup.

Yes but the suction is extremely weak. This is not a viable solution. For that much piping, you’ll do better to get a bigger collection system

I think I would put the vac in a exterior room to avoid the noise.

I'm just a kid but 8 make stuff I used a bauer cyclone separator and a bauer 4 horsepower shopvac

is everything 2 inch?

what micron filter is on the shop vac? It should be less than 1 micron. The fines are going into the vac and coming right back out into the room. The fines are deadly. You could exhaust the vac to the outside through that wall. Then it would be pretty safe.

should take one of those air flow meters at each port and see if they are all the same.

What is the vac specifications?

Great video,
I think your system would work better if you would have planned the vacuum in the middle of the 50ft. Then valves to both sides. When using equipment to eather side just close the opposite valve. Versus the last piece of equipment having the least suction. But easy mod. Great video.

I made one of these for dust collection, I used a HF 4 horsepower vacuum and it works great , if the five gallon bucket starts to cave in the sides , the line has a clog in it and will cause this to happen, picking up aluminum chips will cause this to happen. Great job on the video .

Yes you can

I have a power bar that's made for this type of setup. When you turn on any tool that's plugged into it, there's a slight delay and then the vacuum turns on too.

I have the same sit up although mine is from habor freight with a 5 gal bucket I am now going to be using the 55 gal thanks for the information it helps many 😊

Seems like either the system is not sealed well, or you kept a blast gate open somewhere. The best performance that you can get with any dust collection system will be with only one blast gate open at a time and a very well sealed system.

you could also build a sound proof box for the shop vac to limit the noise

as far as a switch for the vac, you could install a bunch of switches across the room near each piece of equipment and wire them all in parallel.

Too late but the Tee's should have been T Y Sweeps

He's a walking talking ad for Under Armor.

Great video. Gotta say, if a shop vac can create enough suction over that much distance, then my plan for a straight line of about 14 feet should work brilliantly!

Nice video.
A few thoughts. I think people use 5 gallon buckets under a dust deputy or similar because a 32 gallon can full of sawdust is HEAVY. Also, a 5 gallon bucket can be stacked on top of the vacuum to free up floor and wall space.

Very interesting. I hope you have a follow-up video showing the effectiveness when you're using the tools. Thanks for the video.

Just subscribed to your channel because this setup is a lot cheaper than I thought. Thanks for the tutorial. ❤

Hey Alex, great way to showcase the work you've done to improve your shop setup! I actually did a smaller, but similar setup for my garage. I'm using an almost identical sized trash can, and dust deputy, but for some reason my trash can keeps caving in on itself. How did you fix this issue? Thanks!

great video - "small shop" :))

Excellent job!!

Cool vid and a very polite/friendly/genuine comments section. Good job guys, a very rare thing in what is usually a toxic swamp

Nice setup. I have a very small shop and I have been looking at how to make a similar one for my lathe. Thank you for sharing this.

❤❤❤

Does there need to be a good seal on the trash can? I thought if it had a bad seal it would affect the suction.

Do you have a problem with your blast gates, the groves getting saw dust in it and not being able to close it properly?

Craftsmen vacs are made by Shop-Vac. Shop-Vac makes like 75% of the other brands out there..

This is one of the most complete and detailed dust collection setups I've ever seen. Well done!

Thank you so much!! This is what I was looking for. You answered my question about using 2" pipe and a shop vacuum!! Cheers 🍻

Time teaching your children skills and just father time is invaluable. Great looking young man.

Nice work! Now you need a remote for the shop vac

Nice work. Looks like you have your own Dust Collection Engineer there. He’ll be running that table saw before too long. lol.

great video very helpful thank you

Awesome Alex. I like how you can upgrade the system without a major change in the system.

Did you glue the white pvc together or is it just fitted? Thank you