Saturday, November 15, 2014

19th Century Dust Collection Systems

Many of us tend to think of removing wood dust and shavings as a relatively modern concern but the dangers of fine dust to the woodworker go back to at least the mid-1800's. Here are excerpts from an article in the 1873 book, On the arrangement, care, and operation of wood-working factories and machinery; forming a complete operator's handbook, by J. Richards.
The writer having been personally concerned in the introduction of this system in England and the continent of Europe, and having built pneumatic apparatus, that have been in constant operation since 1862, has no fears in recommending the system as practical and economical, apart from its convenience and its sanitary advantages in getting rid of the fine dust so prejudicial to health, and one of the most objectionable features of operating wood machines. 
The fans must be plain, strong machines, large enough to perform their work easily ; the vanes strong enough to break up sticks that may pass into the fan. The bearings should be outside the casing and pipes...
It is often desirable to have the fine dust separated from the shavings and sawdust; even if they are only to be used for fuel, and the magazine or shavings room should be arranged to allow the dust to pass off at the top, as in Fig. 22. 
I used to think my high school wood shop, built in the 1970's, was progressive for having an industrial size dust collection system but Richards discusses similar systems that existed 100 years before I was born. Initially I believed Richards was talking about just ventilating dust from the air but then he mentions floor sweeps and lines dedicated to machines.
Pneumatic Fan
Floor Sweep
...starting with 5 inches diameter for the smallest size for a main pipe, there should be added at least 10 inches of sectional area for each machine that is connected, except surfacing or dimension planing machines, which will need twice as much. 
Health risks from wood dust have been known for 150+ years and the means and will to remove that dust at least as long. So why do I feel like it has been 'rediscovered' as a new concern over the last several decades, at least by hobbyists? Leave your comments below.