Last fall DeWalt introduced a dust-extractor vacuum equipped with a self-cleaning filter system. The vacuum contains two HEPA filters and is said by its maker to be an appropriate machine for collecting lead-bearing dust under the RRP work standard. I have been using a DWV012 since late last year, primarily for collecting dust from a miter saw and sanders, and for general shop cleanup. The machine works fine for those applications and has the power to pick up nuts, small bolts, and drywall screws. But what it’s really designed to do is collect the fine dust produced by sanding drywall, demolishing plaster, and cutting, grinding, and drilling concrete. The manufacturer posted a video intended to show how resistant the vacuum is to clogging while collecting fine dust.
In the video, the operator uses the extractor to empty a bin filled with dry mix joint compound — a powdery material that would clog many vacuums. What’s impressive about the demonstration is that it was performed without a bag, so the HEPA filters were exposed to the entering dust. At the end, the operator opens the tank and it’s filled to within a couple of inches of the top. The filters are practically embedded in plaster, and yet suction never fell off. Without the self-cleaning function, the filters almost certainly would have clogged.
Testing the Machine
Not wanting to take the manufacturer’s word (or video) for what the machine can do, I repeated its test and performed a few of my own. In the tests, I collected wall texturing compound — chosen because it’s cheap ($9 for a 50-pound bag) and has very fine particles. The first couple of tests were not very challenging. I vacuumed about 40 pounds of texturing compound out of a drywall bucket, first with a paper collection bag in the machine and again with a fleece bag. When I opened the machine to remove them, it was clear they had captured virtually all of the dust. What little got through had been pulled against a filter, was knocked off during the automatic cleaning cycle, and then came to rest in the bottom of the tank.
The next couple of tests were more challenging. In the first, I used a plastic collection bag. These open-top liners lie up and over the sides of the tank. They provide no filtering and are typically used to keep the tank clean while collecting slurry from wet cutting applications. I wanted to see if the plastic liner would remain in place (as it’s designed to do) or be sucked against the filters. The bag worked fine and the filter continued to draw while surrounded by plaster. The final test was a repeat of the manufacturer’s, suctioning up plaster with no bag at all. The results were the same as for the test before, only messier because there wasn’t a bag lining the tank.
According to DeWalt, it’s okay to operate the extractor without a bag. For this machine, bags exist to make it neater and easier to dispose of debris.
Self-Cleaning Mechanism
The filters didn’t clog when covered with plaster because the automatic cleaning mechanism blew them out at regular intervals. The auto-clean function works like this: Within three or four seconds of turning the vacuum on, you hear a muffled thump from inside the machine. A few seconds later you hear another one. The thumps are the sound of a solenoid closing a butterfly valve, reversing the flow of air through one of the filters and blowing it clean. It’s a quick blast of air and the valve reopens almost instantly. After this initial cleaning, the solenoids are activated at 30-second intervals, so each filter is cleaned every 60 seconds. Since filters are cleaned one at a time, one is always drawing, but suction is reduced by half during the instant when the valve is closed. I noticed a brief drop in suction when the vacuum thumped as I was picking up plaster. It was little more than a blip, and would not have affected the machine’s ability to collect dust from tools.
Features
Like other dust extractors, the DWV012 has an electrical receptacle to power the tool plugged into it. When the tool comes on, it activates the vacuum, which continues to run for another 15 seconds after the tool is off. A speed-control knob allows the operator to intentionally reduce suction or lower the combined amp-draw of tool and machine to avoid blowing breakers.
The DWV012 has a tough plastic exterior and feels solidly built. It has large plastic wheels on the back and metal casters on the front, one of which locks so the machine won’t roll. Multiple hand-holds — a top handle, a front grip, and a grip between the rear wheels — make it easy to lift or tie down the machine. At the back of the extractor is a handle that retracts for transport and extends so you can roll the machine like a piece of luggage. The top handle functions as a cord wrap, and there’s a clip on back to secure the hose when it’s wrapped around the machine for transport.
At the end of the hose is a twist-lock fitting that grabs onto the dust ports and shrouds of tools from DeWalt’s Perform and Protect line. The connection won’t come loose and the tool can be rotated without twisting the hose. Connectors are available to adapt the hose to older DeWalt models and other brands of tools. I like the positive connection between hose and tool, but the connector is kind of bulky and it’s not easy to determine which adapters fit which non-DeWalt tools.
The extractor can be used without filters for wet collection. I’m sure this would work, but I didn’t actually try it because unless you are diligent about cleaning and drying the machine afterward, the inside becomes a swampy mess.
Bottom Line
I’ve owned a few different dust extractors but never one with self-cleaning filters. That feature alone makes me prefer this machine to others I’ve used. This is not the only extractor with HEPA filters and an auto-clean function, but it’s the only one I know of that sells for less than $500. If you regularly collect fine dust or material that might contain lead, then the DWV012 is worth a look.
For more on HEPA vacuums see “Buyer’s Guide to HEPA Vacuums for RRP Work” in the winter 2011Tools of the Trade.
David Frane is the editor of Tools of the Trade.
