Luthier Tips du Jour Mailbag - Dust Collection

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In this episode, Robbie O'Brien answers a viewer's question about how to control dust in your shop. He identifies four steps needed for effective dust control.

Video Transcription

[on-screen text reads: Luthier Tips du Jour Mailbag]

Mailbag question: How do you control dust in your shop?

Robert O'Brien: Today's Tips du Jour Mailbag question comes from Mike in Philadelphia. "Dear Robert, could you talk some about how you control dust in your shop? Love the videos, Mike in Philadelphia."

[on-screen text reads: www.obrienguitars.com]

Well, Mike, you've hit upon a very important subject. As luthiers, all of us are aware of sharp objects, power tools, hand tools, chemicals, a lot of dangerous things that we work with as we exercise our craft. However, very few of us are aware of, and those that are aware of do little to control the exposure to dust. Over the last 10 years, I've helped my students build well over 500 guitars, and I've started having symptoms related to excessive exposure to dust. So I did some research on the subject to educate myself. I even wrote an article for National Magazine on the subject of effective dust control.

In my research, I went to the US Department of Labor OSHA website, and they had this to say about dust. In general, exposure to excessive amounts of dust is considered to have an irritant effect on the eyes, nose, and throat in addition to pulmonary impairment and is considered a human carcinogen. This next sentence really got my attention because I work with Western Red Cedar. Western Red Cedar dust has also been known to cause asthma. I also found that the smallest particles, those in the 1 to 10 micron range are the most dangerous, and this is known as the PM10 range.

Now, let's put that into perspective. A human hair is just below 100 microns in size [on-screen text reads: How Big is a Micron: 10 Microns - .00039 Inch or .01mm, 1 Micron - .000039 Inch or .001 mm. Human Hair - .0035 Inch or .0889 mm]. So anything below 20 microns is invisible to the naked eye, and that's the problem. It's a very, very fine dust. It becomes suspended in the shop environment. And once it's suspended it blows around for long periods of time, and that presents a problem to you as the woodworker, it gets into the lungs and begins to cause problems.

4 Steps to effective dust collection

So effective dust collection is very involved. There's a lot of research to be done, but basically I've discovered four steps for effective dust collection.

1. Collect the dust at the source

The first one is collect the dust at the source. This is the most important aspect of effective dust collection. Once the dust is up into the shop's air, it becomes nearly impossible to collect and presents a danger to you as a woodworker.

2. Use sufficient airflow at the machine when collecting dust

Step number two. Use sufficient air volume or airflow at the machine when collecting the dust. Now, this is known as CFM, or cubic feet per minute. Most machines in a small shop need 500 CFM or less of airflow. Now, larger machines like planers and joiners obviously need a bit more. There are many things that can affect CFM. Excessively long runs of ductwork, undersized ductwork, insufficient filter medium, all of this can affect the amount of airflow at the machine. So do some homework on this. Do your research about CFM. It's very important.

3. Seperate the bulk of the waste before it hits the vacuum filter

The third step in effective dust control is to seperate the bulk of the waste before it even hits the filter of the vacuum. Now in my shop, I've installed cyclone separators made by Oneida Air Systems. These are advertised to remove 99% of the waste before it even hits the filter in the vacuum. Having a clean filter maintains the efficiency of the vacuum, thus maintaining the CFM at the tool.

4. Filter the dust once its been seperated from the line

The fourth and final stage to effective dust collection is to filter the dust once it's been separated from the line. Why go through all the trouble of collecting the dust in your shop only to reintroduce it into the shop's air because of a poor filter in your vacuum? I highly recommend installing HEPA filters on your vacuum. If you install a HEPA filter on your vacuums, a good quality HEPA filter will filter the dust down to that PM10 range that we're talking about, the 1 to 10 micron range, which is the most dangerous, and therefore it won't be introduced back into your shop's environment.

So Mike, in Philadelphia, this is a very complex subject, but one that is very important. So I suggest that you and other viewers do your homework on the subject and then if you find it necessary, go ahead and invest in a high quality dust collection system so that you can work more safely in your shop. Thanks for the question, Mike, and happy building.

[on-screen text reads: More Luthier Tips and online courses availalbe at www.obrienguitars.com]

StewMac

 

Robbie O'Brien

Luthier and Instructor, Lutherie Academy