A typical shop
consists of several different work stations. Areas around
stationary machinery and around work benches tend to be
where wood debris accumulates.
Although wood debris and dust are standard in every wood
shop a dust collection system isn't. Consisting of large chunks and strips all
the way down to dust particles. Managing
this debris is important and there are many ways to remove
- Remove debris with a broom or shop vacuum.
- Have dust collection systems at each
- Where dust masks to filter particles
- Use fans and open doors or windows to vent your shop.
- Or you can simple ignore it and do nothing.
There are very few shops that are completely clean and
free of dust and debris. Although almost every
wood worker cleans up using a broom
and dust pan but not nearly as many consider the dust
and suspended particles that a broom can't remove (and
often actually adds more to the air).
have been studies recently stating the harmful
or toxic affects wood dust can have. Some
woods like satinwood are classified as a primary irritant
while other are considered sensitizers due to the effect
over extended period of time.
Aside from natural toxins wood workers need to
worry about pesticides and preservatives. Most wood
is labeled as being treated but some exotic wood is difficult
to determine if it has been treated in any way.
alphabetical list of wood species and health hazards
each species can have.
Dust Collection Basics
|It is important to
understand the technical terms associated with a dust
- Static Pressure (SP): Is the
resistance (or friction) caused by the air inside
the duct. Units are measured in "Inches
- Cubic Feet per Minute (CFM):
The volume of air moved in 1 minute.
- Feet per minute (FPM): The velocity
or speed of the air within the duct.
- dBA: Measure of the relative
0 dBA is barely audible while 130 dBA is considered painful.
- Micron: Is a unit describing
the size of a dust particle in this case.
1 micron = 0.001mm
Dust collection and air filtration systems should
be considered when building any wood shop. It is best if
the entire system can be integrated into the shop
design but this can be difficult if you are installing
a system into an existing shop without totally remodeling.
A central dust collection system consists of a central
collection unit and ducting leading out to each machine
in your shop. There are several accessories to go with
your system, some are necessary others aren't.
is usually galvanized straight pipe,
4" - 6" in diameter. It is recommended that you
use 26 - 24 gauge pipe.
can be used but there are some special design features
that need to be implemented. Features like:
- Pipe needs a ground wire run inside of it.
- The pipe should also have a ground wire wrapped around
the outside of it.
It is very important to ground the ducting of
your dust collection system against static electricity.
Metal ducting is much simpler than plastic or PVC simply
because all you need to do is ground both ends of the ducting.
Plastic or PVC needs a ground wire run inside the pipe
around the outside as well.
Failure to take these precautions can lead
to a nasty shock or worse, a fire.
Steps for building your own dust collection system
Special consideration needs to be given to:
- Traffic flow: You want to avoid having
ductwork running through high traffic areas or in areas
where it may affect the safe operation of power tools.
It is important to the performance of the dust collection
system that the ducting doesn't get dented or crimped.
This reduces air flow and may lead to blockages.
- Ductwork arrangement of stationary tools: Especially
true with a table saw. It is difficult to duct a table
saw upwards. The ducting rising up to the ceiling could
be a hazard to the safe operation of the tool.
This is where you will need to find another route
for the ducting. If you have a crawl space then that
is the most practical method.
- Location of stationary tools: It is
important to keep your distances (runs) from the tools
to the dust collection unit at a minimum.
If one tool is unnecessarily far from the dust collection
unit then it may result in a larger unit to service
that run. Move tools if possible to reduce the length
Step 1. Determine your needs
Depending on what size of wood shop you have or the number
of tools you want to add to your dust collection system,
you will need to have a system that will accommodate your
may be able to have a portable system that only services
one tool at a time. This is the perfect solution
for a small shop and certainly the least expensive.
Step 2. Gather information
books, articles and the internet are all great places
to start gathering information on dust collection. You
want to gather information on collectors and filters,
duct work, flexible hose, filter bags, remote on/off
switches and grounding kits. Chart the results of your
information gathering and compare.
Step 2. Be sure to adhere to all local building codes
Some areas have codes dictating where a dust collection
unit may be located or how loud it can be. Checking to
be sure there are no codes or bylaws before you build your
dust collection system may save you money and time.
Step 3. Laying out your system
Air Flow for
CFM Required for
|SP by Duct Diameter
(3500 FPM per 100' of Duct)
||Inches of SP
First draw a layout for your shop. Show locations
of all tools that you intend to hook up to your
system. Locate the collector on this drawing as well.
Determine the lengths of the ductwork and the number of
fittings. Keep in mind that the smoothness of the duct
interior and the number of fittings. These all effect the
flow and could increase the size of your dust collection
When making the transition between larger and smaller
diameters use tapered connectors to avoid restricting the
Remember to keep it simple. For most small shops a basic
system will work just fine. Having 3 fixed outlets dedicated
to the tools you use regularly and flexible hose for those
that are only used occasionally.
Most dust collection units have 2 in-ports for 2 runs
of hose. This will easily accommodate 4 stations especially
if only used one at a time.
A dust collection system collects the large shavings and
smaller particles but is limited in eliminating very small
particles The filter bags are limited when it comes to
dust smaller than 10 microns unless
you get a dust bag that is designed to capture smaller
alternative which has other benefits is to get an air
filter to "clean" the air in your shop. This
is effective in also ridding the air of chemical pollutants
from paint, polyurethane and mineral spirits.
Free article about how to build your own dust