Dust Collection for Orbital Sanders
High-velocity vacuum dust collection for hand sanders is a separate system from the low-velocity system used for larger machinery. June 15, 2014
Question (WOODWEB Member) :
I have a Grizzly 3hp dust collector that I would like to hook up to three orbitals as well as some other hand tools, but I need to hang the hoses from over my bench to prevent any drag marks on my work. Does anyone know of someone who has pre-made manifolds that I can order?
Forum Responses
(Dust Collection and Safety Equipment Forum)
From Contributor C:
Give the guys at Oneida Air Systems a call. We have used them for all of our dust collection equipment and ducting. They are great folks and have engineers who will assist you in determining the most efficient approach to solving your problem! You may also want to consider a bigger collector if you're planning to run multiple machines of stations, again the guys at Oneida can help you there as well.
From Curt Corum, forum technical advisor:
There are two different types of dust collection, high velocity vacuum and conventional dust collection. A dust collector works by moving larger volumes of air at lower suction pressure than vacuum cleaners. A dust collector is not designed to be used as a high-suction vacuum cleaner. High velocity vacuums move low CFM (example 50 CFM, 75 CFM, etc.), but at a terrific velocity or air speed (normally 8,000 FPM). A high velocity vacuum uses small diameter pipes and hoses (1”, 2”). Conventional dust collectors move a lot of air in larger pipes and hoses (4”, 5”, 6”, etc.) at a velocity sufficient to keep material flowing to the dust collector (normally at 4,000 FPM). This type of dust collector moves large quantities of air necessary to evacuate dust hoods on machinery.
Summary: If you try to pull vacuum through a 1 ½” diameter hose on a conventional dust collector, it will be like drinking a milk shake through a cocktail straw. If you attach 2” hose from a high velocity vacuum to a planer hood with a 5” outlet, you will not evacuate the hood. The two sciences do not overlap. They must be treated separately. Most shops should have a conventional dust collection system for the floor machines and high velocity vacuum system for 1" hoses to hand held sanders etc. It is not uncommon to drop a 1 1/2" hose off high vac system to nipple on radial arm saw blade guard and a 5" drop from conventional dust collection system to the radial arm saw hood behind the blade.
From contributor M:
I have been using a Festool CT33 vac with an Oneida dust deputy with my orbitals. I also use it with my other handheld tools, as well as for general cleanup. It should do a good job supporting at least two tools at a time. The dust deputy does a pretty amazing job of separating the fine sanding dust, as well as chips from the other tools. I have probably saved at least $200.00 on bags by now so it has paid for itself. It is also nice since I can open it up and retrieve sanding dust when I need to make wood filler. As mentioned a large central dust collector really does not have nearly enough suction to work right with a sander, or portable tool. They are designed to move large volumes of air with enough velocity to keep the particles or chips from settling out of the air stream. A dust extractor aka shop vac has far more suction.
From Contributor T:
I don’t know if this is an option for you but in my shop all the sanding is done on a 4'X6' Denray downdraft table. It does an excellent job of keeping the shop clean and I don’t like wearing particle masks. Sometimes there will be up to four guys sanding on the one table provided the parts are small enough. Also the table gets used as a work surface - I don’t know what I would do without it.
From Contributor T:
Curt: If I understand this correctly the original poster can use his 3hp Grizzly dust collection system for a downdraft sanding table. Just make a box with a grate on the top and a 6 or 7" inch outlet to connect the dust collector.
From Curt Corum, forum technical advisor:
You are absolutely correct. Attaching the Grizzly to a downdraft table would be a volume scenario vs hi-vac. You just have to make sure open area is relative to the air volume the Grizzly will provide. Prior to self-contained downdraft tables they were usually attached to a central dust collection system or dedicated volume dust collector.
