Airborne dust

[Kurt Cady]

I have one of those $10 white box fans in my 'shop' (one side of a two car garage) that I keep running when I'm working. An air filter is just not in the cards at the moment. I'm wondering if I can get a fan like the one below and put it in the center of the empty car space aimed at the open garage door, if it would help the air quality and the cleanliness of the garage. Anyone have any advice, experience with this idea?http://northerntool.digby.com/shops/web/northerntool?cmd=item&itemId=250679&vendorId=110

[Rod Sheridan]

Hi Kurt, if you're going to use an exhaust fan, it means that you're not capturing the dust at the source, and therefore you are inhaling it.

In that case I would do two things

1) Wear a good dust mask and don't track dust into the house (change your clothes)

2) Use an exhaust fan so that the air is sucked out of the shop by the fan, and of course have an intake opening at least as large as the fan. Locate the intake and exhaust on opposite sides of the shop if possible.

The fan you've shown could be OK, however you would better off with a used furnace blower, you may be able to get these for free from a local HVAC mechanic.

Regards, Rod.

Simply putting a fan in an open garage door will cause a lot of the discharge air to be recirculated into the shop, not a good plan

[Greg Peterson]

+1.

I started a reply last evening, but thankfully I shut it down. Rod pretty much nailed it.

There are two dirty little secrets in wood working. 1) You can never have enough clamps. 2) Dust collection is challenging, especially on a budget.

It can be done inexpensively, at least in relative terms. But the idea is to capture the dust before it gets into the atmosphere. Once it gets 'loose' there are a number of measures you can use to eliminate it. Yours may work.

I am reluctant to say your solution will work, even with Rod's recommended configuration. You, and your families long term health, are the consideration here.

Wood dust is not a healthy thing to inhale. Wood chips, or what the layman calls sawdust is harmless. It is the particles that are unseen by the naked eye that cause the harm to lungs. These particles will stay suspended in the air a long time. And once they settle, the slightest disturbance will kick them back up into the air.

I would suggest you focus your resources on capturing dust at its source. This thread will get you headed in the right direction: http://www.sawmillcreek.org/showthread.php?149338-HF-Dust-Collectors&highlight=thein+%2F+Mcallister

[Howard Acheson]

You can easily make a quick dust filtering fan by using one of the 20" fans and cover the intake side with a 20x20 air filter. Some folks just use duct tape to attach the filter. I made a frame so I can just slide filters in and out.

With proper placement to get air circulation, you don't need to even open a door. The fan will circulate the air and clear it of dust. It also ensures that if you are looking for personal cooling, you are getting clean air.

It's quick and dirty but cheap and effective.

[Kurt Cady]

Before we go all get into the crazy dust debate, let me add a little additional info.

I always wear my 3M half mask respirator.

I have a Jet DC-1100 that I don't have operational yet due to power issues. And will be getting a Wynn Filter. But let's be honest, dust collection at the source doesn't get built in a day.

I was just looking for a way to keep the garage cleaner, and hoping others would have some experience with fans or the like.

Thanks for the responses, guys.

[Greg Peterson]

Sorry Kurt, I wrongly assumed you had no DC capability. In my experience, using two box fans to draw air 'through' the shop was minimally effective. So long as the breeze was moving in the right direction, the two box fans moved some air through the shop. Nothing noticeable. If the breeze changed direction, the fans become less than helpful.

The fan you show boasts several thousand CFM. It may be as effective in a two car garage as the ceiling fan in a bathroom. Placement is the issue. Likely a fine line between creating a vortex and exhausting the particles out and away from the shop.

Yes, DC at the source is an ever evolving. I wish you the best of luck in your endeavors.

[Steve Mellott]

Kurt:

If you want a free furnace blower, let me know. I travel to Norcross nearly every weekend and could meet you there.

Steve

[John TenEyck]

You can easily make a HEPA rated dust filter every bit as capable as those that will set you back several hundred dollars, for not much more than the cost of the filter and an old blower. I bought a HEPA filter from Grizzly, about 14" square for around $15. Build a sealed plywood box, put the blower inside and the filter in the open front, and you are in business. I don't mean to make light of it, but if you look at the commerical units they are nothing that you can't make yourself and your home built will work just as well. Just copy the filter area and CFM of a unit recommended for your size shop. Mine does a great job of scrubbing the air of the fine stuff that always seems to escape during the various milling operations.

[Kurt Cady]

No worries, Greg. I should've added all the info. I know the best place to try out ideas before diving in head first is here. Someone is bound to have tried it before!

[Ole Anderson]

My early attempt at cleaning the air was a 20" box fan with an 89 cent 1" furnace filter as a pre-filter doubled up with a 1" filtrete filter to polish the air, so to speak. Sort of worked, but a box fan just doesn't have the stones to move much air thru 2 filters (high volume but no pressure to speak of). Check the horsepower on a box fan, then consider a 1/3 hp old furnace fan as already suggested.

[Joe Angrisani]

You can easily make a quick dust filtering fan by using one of the 20" fans and cover the intake side with a 20x20 air filter. Some folks just use duct tape to attach the filter. I made a frame so I can just slide filters in and out. With proper placement to get air circulation, you don't need to even open a door. The fan will circulate the air and clear it of dust. It also ensures that if you are looking for personal cooling, you are getting clean air. It's quick and dirty but cheap and effective.

Somehow I don't see a furnace filter stopping the sub-1 micron dust that does the real damage in our lungs. Any thoughts, Howard? As Ole said, a box fan can't really draw effectively through any filter that will actually stop the small stuff.

[Jim Neeley]

I don't want to start a battle but you're dead-on, Joe. Conventional furnace filters are known in the heating and ventilation business as "rock catchers" because of the relatively large size particles necessary they stop. Not to say a furnace filter won't catch *some* of the dust but those larger particles would fall to the floor quickly in still air anyway.
Along the way they're pumping a lot of the dust back into the room.

[Jim Neeley]

Personally, I'm looking forward to the round of posts that'll get posted once the Dylos purchase goes through and a number of us can post our quantitative findings.

I for one have a Jet DC1100 DC and a couple of the Jet AF-1100B air filter units. I'm planning on ordering the Wynn filters for both but want to get some "before" numbers first. I'm pretty sure others have similar plans. :-)

[Greg Peterson]

Jim,

I got in on the first round of the Dylos group buy. I use it all the time. The results never cease to surprise me. When I think I have come up with a great DC idea, the Dylos will tell me otherwise. According the monitor, the AF-1100B definitely scrubs the air in my modest sized shop in very short order.

When the static count (shop has been unoccupied for 24 hours or longer) gets high, I clean shop. Open the doors and window, blast ALL horizontal surfaces with air or vacuum exhaust, vacuum floor and horizontal surfaces, close up the shop, place box fan on floor and put the Jet on high for a couple of hours. Still working on getting a shop wide vortex working. My shop is L shaped so there are places that resist this effort.

I opted for the .5 / 2.5 micron Dylos unit. My thought at the time was if I can control the .5 micron particles, the 1 micron particles would follow. My .5 particle counts are usually in single digits. When they go above 30 in a static environment, its shop cleaning time.

[Kurt Cady]

Your counts are in the single digits while you're working? Or after the air cleaner has worked?

[Greg Peterson]

Certain activities cause the numbers jump into the hundreds for a short while. My collection at the source is still a work in progress. Some activities are extremely challenging to implement DC on, such as routing. Dadoes, rabbets, cutting tenons on the table saw cause pretty good spikes on the meter as I have yet to find a good above table DC solution for these cuts.

The particle count quickly returns to acceptable levels during work (50~ or lower). I can live with the occasional spike in particle counts.

I don't like my work space to get cluttered with debris, so I vacuum frequently during my shop time. Despite my efforts, some activities simply defy dust collection.

[Jim Neeley]

Sounds encouraging, Greg... FWIW this spring, with a winter's worth of fine dust accumulation in the nooks and crevises, it was time for spring cleaning. I've got a pretty good size (5hp I-R) compressor with a Typhoon nozzle but I noticed that while it blew the dust off well, there wasn't a large enough "tube" of moving air and it didn't move far enough to really clean the way I wanted. A friend loaned me his electric leaf blower and, with a mask dawned and about 20 minutes the place was pretty darned clean. My compressor gets frequent use but for deep cleaning it's tough to beat a leaf blower.

Well, unless I was to disconnect the discharge on my DC fan.. Hmm... <eg>

[Greg Peterson]

Jim - I hook the vacuum hose up to the exhaust port on my shop vac to get a nice wide stream of air. Between the air compressor and shop vac, I can visit all the wonderful places dust likes to settle down and call home. Once I get it airborne I can capture most of it.

You will quickly find yourself constantly shooting a quick glance at the Dylos to see your levels. Kind of addictive. And definitely necessary to gauge DC solutions you may implement.

I consider the Dylos unit as important as any of my setup/calibration tools. Engineer squares, 3-2-1 blocks, dial indicator, master plate, straight edge. Life in the shop would be a whole lot less productive without these.