http://www.woodreview.com.au 91WORKSHOPSRemember, 350cfm won’t provide adequate flow for the
collection of fine wood dust. For this reason alone, an early
decision I made was to avoid 100mm duct and choose
150mm as standard. The difference is significant with
the area of 150mm duct approaching three times that of
100mm. Of course 150mm ducting will not connect to the
majority of standard hobbyist equipment which brings us
to point three.
- Modifying machinery to achieve
greater airflow
Unfortunately, machinery manufacturers have for
many years condemned woodworkers to ineffective
dust extraction through the design and placement of
dust ports. As such, choosing machines that provide for
direct connection of 150mm ducting or more commonly
modifying existing machinery will be necessary to achieve
improved fine dust collection. Modifying professionally
made machinery is a concept I personally struggle with.
Nevertheless, with the types of inadequacy shown in
some machinery the need becomes quite clear and there
are considerations that extend beyond the physical
upgrade of the port.
Just as important is ensuring there is adequate ventilation
within the machine to support the airflow requirements
of the larger port. Most of this can be learnt through trial
and error, however, be prepared to dedicate time to this
work if you are to improve the collection of fine dust at the
source. Photos 5–9 provide some examples of the type of
modification required to deliver improved outcomes.
Clearly an article of this scope can only hope to introduce
a number of the concepts specific to an effective dust
extraction system. As a minimum, reflect on what was
discussed in Point 1, i.e. ensure your current extractor
vents outside the workshop and consider some form of
forced ventilation to assist in the removal of fine airborne
dust. Should these not be possible then of course ensure
that you wear a properly fitted quality dual cartridge
filtered respirator. These three things alone should
significantly contribute to lowering your long term
health risks. Beyond that, the unique nature of your own
workshop and preferred methods of work will require a
range of considerations and possible solutions outlined
in points 2 and 3. The desire here is to create curiosity in
whether your current extraction system is consistent with
managing the health risks associated with your chosen
methods of work.In my case that curiosity was initiated on the discovery
of the fine dust lining the walls adjacent to my previous
extractor. Having made that discovery and subsequent
investment in a number of the leanings shared here, I’m
now appreciating a renewed enjoyment of woodworking
through the long term health benefits that come from a
more effective dust extraction system.Photos 1–4: Troy McDonald
Photos 5–9: John McConnell- An extensive upgrade to a 14" bandsaw illustrates what can be
achieved: 150mm main port and 100mm sub ports to both above
and below the table. - Providing adequate ventilation to feed a larger port is critical. Here
the front door on the bandsaw is slightly wedged open to ensure
adequate air flow to the upgraded 150mm port.
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Troy McDonald is an engineer and woodworker based in Brisbane.
Email him at: [email protected]