$5 Drywall Dust Water Filter Gadget for Shop Vacuums

Drywall dust will either frequently clog filters, or rip your filter. Drywall dust will also wreck your vacuum motor.

Typically vacuuming drywall with a shop vacuum will also end up being redistributed through the air from your vacuum.

This is a cheap gadget to filter drywall dust without needing a cyclone, or hepa filter, or an external water filter bucket.

You will need:

1. A wet/dry shop vacuum cleaner to connect this gadget to.
2. Two 1 1/2" ABS elbow pipes (measure to fit )
3. A small length of 1 1/2" ABS pipe to fit your vacuum (measure to fit).
4. Water
5. A few drops of soap.

Step 1: Measure Available Width of Vacuum Host Inlet.

For shop vacuums, this seems to be about 1 1/2" available if your hose is about 2".

The fit does not need to be exact, and ABS pipe comes in many sizes, just find the closest fit.

Since shop vacuums tend to be angled (so that debris doesn't go flying into the filter), you need to measure what's available to you, not the total inner diameter. In my vacuum I've got about 1 1/2" available.

Use this measurement to buy the appropriate ABS elbows and appropriate ABS pipe.

For my shop vacuum my buy list was:

Two 1 1/2" elbows (about $1 each ).

Small length of 1 1/2" pipe (about $1.50/foot ).

Step 2: Cut ABS Pipe to Be Approximately Height Between Outlet and Bottom of Canister

Cut your ABS pipe to be slightly less than the distance from the inside of the bottom of your vacuum to where the hose connects.

Inside your vacuum canister the hose inlet will be angled to deflect debris from your filter, just find an angle that works best with your vacuum.

The length can be in-exact, it will be angled slightly downwards, and the angle does not matter.

Step 3: Connect the Elbows to the ABS Pipe

Connect one elbow pipe to each end of your cut ABS pipe.

Do not glue the ABS pipe together, the pieces will be snug enough together for this gadgets purpose, and you may need to adjust the angles of the pipe.

Step 4: Push Your Pipe Into Your Vacuum Canister

It should feel snug, but does not need to fit exactly.

Step 5: Fill Canister With Just Enough Water to Slightly Go Over the Bottom Elbow.

Put in a couple of drops of soap. The water will churn like crazy and make many bubbles. Some bubbles is good (traps the dust), too many bubbles is bad (will shoot out of your vacuum).

Then, put in just enough water to just cover the bottom elbow.

Step 6: Turn on Vacuum for a Few Seconds to Test Foaming

You want some foaming, it will help trap the dust.

This picture shows what a good level of foaming will look like. This is with only a few drops of soap.

Step 7: Vacuum Your Drywall Dust

That's it, just make sure your shop vacuum water filter is on (usually just a foam sleeve) and start vacuuming your drywall dust.

All of the dust should end up being trapped in the water ( instead of the air, your lungs, and your vacuum motor ).

The video in this step shows the muddy water after vacuuming the drywall compound dust.

Comments

[MoralC]

You state, "This is a.. gadget to filter.. dust without needing a... external water filter bucket"

But this is a external water filter bucket!

Just saying.

[schouk]

Man I signed up for this site just to say thanks for the great idea. I just finished cleaning up a 400 sq ft room that I sanded yesterday. Didn't have to stop to clean the filter, and there was zero dust in the air. In the past I have had to repeatedly stop to clean the filter as the shop vac bogged down, and it looked like a fog in the room due to dust getting by the filter. Thanks again.

[jandrews32]

Heck yeah man. Me too!

[n8r0n74]

I implore people not to attempt this ill-conceived method.

It won't keep from shooting drywall dust into the air, and worse yet, it very well may replace you damaging your vacuum motor with damaging wherever you're vacuuming, with water. First of all, when the vacuum runs, the water level does not stay flat. It churns like mad, so even if the whole lower elbow is submerged when the vac is off, it probably won't be when the vac is on. This means that some dust (a sizable share in my case) doesn't flow through the water "filter", but gets passed through the vac's filter (which can't remove dust this fine) and then gets blasted back into the room.

Worse yet, if your vacuum is modestly powerful, it can and will actually suck water out of your tank bottom, saturate the filter, and then shoot it out the exhaust ports. But, it doesn't do this immediately. It takes time to saturate the foam filter. For me, between 30 seconds and 2 minutes passed after turning on the vac before it started shooting water everywhere, damaging my floor and drywall.

If you are going to try this (not my advise), make sure you have a second person whose only job is to watch the exhaust port, with a towel. The moment the exhaust starts spitting water, have them shut it off. Within seconds, a trickle of water can become a gusher, and ruin your project.

Again, better just to buy a cheap consumer-grade vacuum, pre-sweep as much dust as possible, then accept that you may ruin the vacuum you use at the end. Better than water damage, by far.

P.S. Yes, I followed the instructions here exactly. Everything was implemented as suggested in the howto.

[ghostrider55]

it works. been sanding for an hour and no hazy white cloud. the its full ball sets every now n then but i just empty and refill and start again.

[jackpot100cid]

To those who may read this, I would be careful using the elbow at the bottom and submerging it in water. Two things potentially could or will happen if you do. The first, the more bends there are, the less suction there will be. Vacuum is strictly air flow, the straighter the flow of air, the greater the suction. The second, submerging the elbow in water will completely cut off the flow of air. Now the vacuum motor is being stalled, working very hard to move air(other than what leaks around the lid seal). What it will do is, create a "water dam" in front of the elbow. It will draw the water away from the elbow until it achieves air flow. This is the same as holding your hand over the end of the hose and you hear the sound level rise dramatically. This will also shorten the life of your vacuum if you use it a lot for drywall or other dust. What I suggest is, do not use the bottom elbow and, stop the straight down pipe about 4 inches from the bottom. Then, put about 3 inches of water in the bottom. Picture the inside of the pipe, it is filled with moving air. When the air comes out of the bottom of the pipe, its natural path will be a natural curve all on its own back up to the filter. The dust will contact the water instantly and stay there while free air moves on. This is a GREAT idea though, just needs a couple tweaks.

[ghostrider55]

i ran a vent 90 degree elbow and a short tube on the end it it seems to work very well.

[JBEARRR]

Yes, great idea. Professional handyman here. This works very well, but do not submerge inlet pipe in water! Will work best if 1-3 inches above the surface of water. Most present day wet/dry vacs have reusable and washable filters that are already included with the vac at time of purchase, or can be purchased separately. I would definitely advise using one of these as they can be cleaned/rinsed and do a fantastic job at collecting any dust lucky enough to not drown. I personally have never added soap to the water, but might try it next time. TBH it seems like an unneeded step though, as I’ve always had great results with just water.

[RockStone]

Just want to correct jackpot's post. .. the water will not stop the flow of air. the motor creates low pressure within the body of the shop vac. outside air is at atmospheric pressure. .. air will move from high pressure to low.... that's just physics...

Akso, the inside pipe is necessary because the incoming dusty air must move through the water for the suspended particles to enter the water. surface tension of water will hold the dust particles to the water while clean (ish) air passes through.

Too much soap creates excessive bubbles which will exit the machine. same thing with Too much water.

Cheers!

[cikasfm]

The idea is to make an actual "water filter" like in $500 home vacuums ( ), but used for stuff like dry-wall dust & etc by a simple modification of your current Wet Dry Vac.

I doubt this would really have a big impact on the lifetime of 4 HP+ motors that are used in most of Wet Dry Vacs these days.

[ghostrider55]

it works. rather well to i might add. cost me about 15 dollars to make but i can sand and still not see any dust.

[Vacman]

Am looking as well for a similar solution. Yes. drywall dust, flour etc is a killer for conventional vacuums, central vacs. A twist on this could be using a secondary collector bin extended with a length of hose a good distance away from the primary machine or motor. With or without the water trick or even a bag. As long as its a good distance away, less likely that dust will come back to the machine and the slight loss in power could be ignored.

[FstarockaB]

the soap for rental carpet cleaners is a non foaming type, and real cheap at stores. Wd be a good option! Goonna try this with my media blaster and see how it works. Def cheaper than a $50 dust cyclone doctor filter - plus its integrated which is AWESOME. Great write up. ive known about water filtering but never thought to adapt it for media blasting :o

[Chazbo54]

The foaming action you want to help trap dust.

[Chazbo54]

Jackpot, hmmm, you may be right. I may try as you suggest to see how much if any
dust gets thrown back out. If too much, perhaps a partial 'air escape'
might do. Like the little band around the pipe in older vacuums to
'adjust' the amount of air. Still a bit more strain but 'ok' for the
motor? I'm also thinking that if the water used is small enough, the
strain may not be enough to cause harm anyway. I'll plan to 'listen'
for strain.

[TailsL]

not bad,you better do some small holes at the end of the plunger to reduce bubbling and improve effectiveness.so you can add more water and forget soap.

[ArthurP16]

Do I still need to have a filter in the vac?

[benderjamesbond]

You don't need a filter. The dust will go through and be captured by the water, and the resulting foam from the soap.