# Dryer duct as Dust Collector piping



## HanselCJ (Feb 11, 2010)

So after tripping over and losing stuff in piles of dust from my various projects, AND finding an increasing amount of saw dust and wood chips in my house, I broke down and bought a dust collector system. Luckily for me the near by Harbor Freight was having a sale and I had a coupon so the big 2hp collector is mine. They were lacking the accessory kit that contains all the gates, connectors and a big section of hosing. With out any other options in town I have to wait till they get them in next week. I wanted to get some cleaning done and test out the unit so i scrounged up a 10' section of 4" dryer duct I had collecting dust. I used the bare pipe kind of like a vacuum around the shop, and let me tell you that thing will suck your face off if you are not careful!

To get to the point, the dryer duct worked great for the 20 minutes or so that I used it. I know the harshest stuff it is supposed to see is dust, not wood chips, but has anyone tried to use the stuff as DC hosing? It is the right size, and compared to 30 bucks for a 10 foot section like I see online, it is the right price. Anyone have any experience?

-Chase


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## Julian (Sep 30, 2008)

I prefer to use pvc pipe. I think the gauge of metal in what you are using is quite undersized.


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## 1yeldud1 (Jan 26, 2010)

You will have much better ari flow with PVC pipe then the dryer hose - better air flow = better dust control


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## Wood_smith (Feb 12, 2010)

Some people say you should ground your dust piping (especially plastic, as far as static electricity goes); some people say you don't need to. I have mine grounded, if for no other reason than a mild shock with the dry winter air.

This is often a hotly debated item….


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## 1yeldud1 (Jan 26, 2010)

We have a machine at my place of employment that uses large metal filters to filter EMD oil. One of our filter suppliers switched to an all "plastic" filter. All was well until we noticed that the oil flowing over the filter was causing an static electric charge causing the filter to "arc" onto the metal frame of the machine - not a good thing when hundreds of gallons of oil are involved in the filter process - could have been an ugly fire !!!!!!!. We immediatly switched back to an all "metal" filter and our problem was solved. I never gave it a thought about the PVC pipe and the "dust" from a wood shop. I guess if the conditions were right you could have an explosion similar to a grain elevator - any thoughts on this subject ????


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## TopamaxSurvivor (May 2, 2008)

All the metal in a building should be bonded together so there a "0" electrical potential between them.


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## 308Gap (Mar 6, 2010)

I deliver gas, and plastic buckets are NOT allowed because the hold a static charge until given a ground point. Moving trucks have to stop completley before entering loading rack as to dissapate any static in the truck. Look at your household vaccums plastic parts. I have my dust deputy wrapped with wire and grounded with alligator clips to the house ground. Thin wall PVC from a irrigation supply is cheapest, its used for drain pipe here. I paid 2.00 for each 8ft section, and got 6 chipped for free.


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## Sawkerf (Dec 31, 2009)

That dryer duct is probably a light gauge equivalent to standard 4" HVAC duct. It should work fine as long as it isn't in a location where it can get bumped and thumped very much.

When you set up your system, use as much smooth walled ducting as possible and keep the spiral, flex, hose to a minimum. Thar stuff kills air flow in a big way.


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## Wood_smith (Feb 12, 2010)

...and a dusty memory from physics class floats back into my mind, that the non-smooth piping (flex, etc.) causes more air turbulence and therefore more static?


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## manumurf (Mar 4, 2010)

Lightweight metal duct (or plastic dryer duct) may collapse with enough suction and a blocked intake. Blowing air through a pipe is quite different than sucking air through it.

You'll be better off on the long run using real Dust collection hose or PVC, or ABS pipe.


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## japanesewoodworker (Jan 16, 2010)

I am a retired Safety Engineer and I have design ventilation systems for the past 30+ years.

The reason that you do NOT want to use "*dryer duct*" for your ventilation system is that the "ribs" on the inside of the duct creates tremendous dynamic and static "friction". This friction put a "drag" on your fan and motor. Thus making it less effiecient. (unless you want to waste electricity)

The previous post about an ungrounded ventilation system made from PVC causing a static electricity and causing an explosion or fire, has happened. I have worked for insurance companies that have paid on these types of claims.

What is the "best" material ?

I agree with Michael Murphy that the best is lightweight galvanized metal duct, with 90 degree elbows kept to a minimum and the fan and motor rated for the system. If you are only going to use a TABLE SAW, and no other wood dust generating machines the you "might" get away with it. (I don't want to "risk" my house & shop on a PVC system.)

I do NOT work for Oneida, but I think they have one of the cyclone collectors and they have a "service" that will give you an "estimate" for a professionally installed system. The only draw back is that when youu buy a new piece of equipment you will have to have the system re-balanced.

You must operate a "balanced" dust collection system if you want the system to collect the dust with the LEAST amount of engery consumed.


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## ND2ELK (Jan 25, 2008)

I got all my duct work from Penn State Industries. Dryer duct is too light and I feel you would have problems with it down the road. I used the economy grade pipe from Penn State and it worked great. I did a blog about my dust collection system and how I put it in if you care to look.

God Bless
tom


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## HanselCJ (Feb 11, 2010)

Wow, quite a conversation starter this thing seems to be. I can see the desire for straight wall pipe, though the ribbing effect can actually reduce flow loss in some sizing of pipe due to increased reynolds numbers. Does the "official" DC spiraled ducting have a smooth interior, and only spiraling on the outside to prevent collapse?


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