Woodstock SHOP FOX W1687 Owner's Manual page 24

Model W1687 (For Machines Mfg. Since 9/11)
Metal.Duct
Advantages of metal duct is its conductivity, efficiency,
and that it does not contribute to static electrical charge
build-up. However, static charges are still produced when
dust particles strike other dust particles as they move
through the duct. Since metal duct is a conductor, it can
be grounded quite easily to dissipate any static electrical
charges.
There are a number of options when it comes to metal
duct, but metal duct that is specially manufactured
for dust collection is the best choice. When selecting
your metal duct, choose high quality metal duct with
smooth welded internal seams that will minimize airflow
Figure.23..Examples of metal pipe and
resistance. This type of duct usually connects to other
components.
ducts or elbows with a simple, self-sealing clamp, is very
quick and easy to assemble, and can be readily dismantled
and re-installed. This is especially important if you ever
need to change things around in your shop or add more
tools.
Avoid inferior metal duct that requires you to cut it to
length and snap it together. This type of duct is time
consuming to install because it requires you to seal all
the seams with silicone and screw the components on the
ends with sheet metal screws.
Flexible.Duct
Flexible hose is generally used for short runs, small shops
and at rigid duct-to-tool connections. There are many
different types of flex hose on the market today. These
are manufactured from materials such as polyethylene,
PVC, cloth hose dipped in rubber and even metal,
including steel and aluminum.
The superior choice here is metal flex hose that is
designed to be flexible, yet be as smooth as possible to
Figure.24. Example of flexible metal duct.
reduce static pressure loss.
There are also many kinds of pure plastic flexible hose,
such as non-perforated drainage type hose and dryer vent
hose. Drainage type hose, while being economical, does
not quite have the flexibility required for dust collection.
The inside of the duct is also deeply corrugated and
can increase the static pressure loss by as much as 50%
over smooth wall duct. Dryer vent hose, while being
completely flexible, is non-resistant to abrasion and has
a tendency to collapse in a negative pressure system.
We DO NOT recommend using dryer vent hose in your
dust collection system. If using flex-hose, choose one
of the many types that are designed specifically for the
movement of solid particles, i.e. dust, grains, and plastics.
Figure.25. Example of flexible hose.
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