# dust collector plumbing



## kansas (Apr 7, 2008)

I just bought my first dust collector and need to run tubing. I've read some on the net and am tempted to use PVC as it is smoother on the inside. My collector is a Delta 50-850 with the cannister. One source says you need 6" ducts all the way to the tool including the adaptor or you won't catch the small harmful dust. Has anyone used this size with a mid sized collector similar to mine? What is your experience with static electricity?


----------



## 33706 (Mar 5, 2008)

On the static issue, definitely run some bare copper or steel wire inside the ductwork all the way to a electrically grounded surface if you're using non-metallic tubing. In my shop, I use one inlet for a variety of machines, so I ran a 10-24 screw to terminate the wire inside, and clip on a jumper wire from the screw to whatever machine is currently (no pun intended) connected to it.


----------



## boboswin (May 23, 2007)

I'm just putting the finishing touches on a small system that I ran with 6" spiral tubing .
It was much cheaper here than 6" PVC.
I used a home built 2 hp cyclone system and separated the intake from the tools into two 20 foot zones to maximize static pressure. 
So far my tests on each tool suggest that I have adequate collection with the exception of the 18" bandsaw which is "marginal". I will do some tweaking on it to improve the pick up of dust nearer the lower guides.
As far as the fines are concerned, I still prefer a stand alone ambient dust unit set to trap the fines that end up in the air regardless of the DC. 
In addition the DC, yields around 70-75 DB of noise so I try not to leave it on for too long as it's annoying.

Cheers

Bob


----------



## DaveHerron (Jan 21, 2008)

Metal pipe is pretty cheap. It is the fittings that break the bank.

PVC pipe. Shouldn't be any kind of problem for a home shop. Running wire inside the pipe is not going to accomplish much. See: http://home.comcast.net/~rodec/woodworking/articles/DC_myths.html


----------



## sIKE (Feb 14, 2008)

Running copper wire though the pipe will work. I do recommend that you take the wire outside and jump over any Wye or Tees. You will need to do the same thing on that run. About 4-6" for the junction take the wire out and join it to min runs wire with a wire nut then put it back into the pipe. Use silicon to seal the hole up when you are done. I also ran copper wire on the outside of the pipe at all runs back to a cold water pipe in my shop. Seems to work very well.


----------



## boboswin (May 23, 2007)

Hi Dave:
"Metal pipe is pretty cheap. It is the fittings that break the bank."

You have me curious now as I thought I did my homework.

I paid around 5-6 bucks for 45's and 90's. 
Splices were about $3.00.

Saddle take offs to 4" gates ran about $6.00 each.
I stayed away from T's and Wye's as they were pricey. ( $14.00 - $17.00)
What are you folks paying for similar in PVC?

p.s. the metal gates and flex tubing hurt pretty good too. <g>

Bob


----------



## chriswright (Nov 13, 2008)

My dad ran PVC for his collector. He used wire in the tubes to ground it out. I'm not sure how big of a pipe he used but if the draw is strong enough I'd think it would pull anything that went near the opening. Remember, most tools only have a 4" dust port.


----------



## Padre (Nov 5, 2008)

Newbie question: I have a SECO UFO-101, 2hp, 240v dust collector. It has a 4" inlet. Why would I run 6" tubing? Wouldn't it be just as effective to run 4" tubing? Most larger tools have 4" outlets, and some even have 2 1/2" outlets. Thanks!


----------



## waroland (Oct 5, 2007)

It has been proved that a small shop dust collector using PVC pipe will not generate enough static electricity to cause flash fire in the pipe. I used PVC in my last garage/shop for years and had no problems. I had a pretty elaborate set-up. In a home shop you will probably only use one tool at a time which reduces the risk of large static charge.


----------



## odie (Nov 20, 2007)

I personally would attach flex to each machine and move the dust collector to each. That dust collector just isn't that big.


----------



## boboswin (May 23, 2007)

Padre:
I had to look up a picture of your dust collector to try to answer your question.
I appears or be a low priced off shore model with a questionable hp rating on the motor and no doubt a less than standard impeller to prevent motor burn out.
Putting a restrictive 4" intake on it helps prevnet the impellor flrom reaching speeds that might burnout the underpowered motor.
It gets quite complicated but if you are interested beyound this brief explanation I suggest you visit Bil Pentz website where it is discussed more fully.

Cheers

Bob


----------



## 8iowa (Feb 7, 2008)

Testing has shown that the air flow inside the pipe needs to be at 3500 cfm in order to suspend fine dust particles. Increasing the diameter of the pipe decreases the air velocity, perhaps to the point where dust will accumulate in the piping system. Conversely, decreasing the pipe diameter will increase the flow rate. Many woodworkers are troubled with this little bit of engineering analysis.

Thus, if the motor in your dust collector is 1 1/2 HP or less, using a 6" pipe or possibly even a 4" pipe may yield unsatisfactory results. Woodworking author Nick Engler takes us thru the math in this short video clip;

http://www.shopsmithacademy.com/SS_Archives/SS109/SS109_Dust_Collection.htm


----------



## 33706 (Mar 5, 2008)

Whether or not grounding makes any difference in the potential for fire sparked by static discharge, I'd hate to have my insurance examiner looking at the ungrounded charred remains of my woodshop sawdust ducting. Compliance trumps logical reasoning every time. It's a money thing for most of us.


----------



## GaryK (Jun 25, 2007)

I agree with not needing a ground wire if your DC is less than 3HP.

Fine woodworking did an article saying the same thing.
Issue 153 page 48

I have 4" PVC with the longest run of about 60 feet and I have no problems at all with my 2HP DC.
I usually have only one or two gates open at a time.

I hardly ever close the one on the table saw (Unisaw) and just open the others as I need them.

I also burried my pipe under my concrete slab.


----------



## 33706 (Mar 5, 2008)

Beech Pilot Barry sez,"*Compliance with what? Old wive's tales?"*

I think the point I was trying to make was that if either your property insurance policy or municipal Code Enforcement statutes REQUIRE that your system be grounded, any 'debunking' is moot. Just like lightning arrestors are often specified in building codes for use in antenna wires, whether or not they actually provide protection is debatable…but again if the building burned due to it getting struck by lightning, I would not want my coverage jeopardized by my own arrogance.
Are you aware of what code requirements are in place for the shop in your municipality?
Remember also that when a co-worker is using flammable solvents elsewhere in your shop, the ambient vapors will be pulled into the ductwork. 
Come to think of it, I've used seat belts and helmets for 40 years and haven't needed them once. Yet.


----------



## kansas (Apr 7, 2008)

Thanks for the input thus far. I'm getting a lot of great input in short order. I've looked at the information Bill Pentz provides and looked at a couple of the links he provides on his site. I also just watched the Nick Engler video as recommended by 8iowa. From what I read on Bill Pentz site I should take the 4" outlet adapter off my machine and replace it with a 6" to reduce restriction and even try to get 6" pipe all the way to the tool if possible. Delta "claims" the 50-850 is rated at 1200 cfm and 11.4" s.p. however Bill Pentz says most manufacturers don't rate them realistically. Basically it sounds like I'll get a stronger "suck" with smaller pipe but will not move the volume needed to collect the harmful particles. If I go with the 6" and the machine can't create enough velocity it will clog or perform poorly. Has anyone tried 6" with a small machine like mine?


----------



## GaryK (Jun 25, 2007)

The harmful particles are the one that float in the air and make their way into your lungs.

Any type of vacuum regardless of volume will suck those away. If your normal breathing will suck them in then imagine what any dust collector will do.

The chips that will cause you problems are the heavier ones. Using a machine without the DC on allows the dust to collect in the bottom and they will tend to stay there no matter the volume or suction power you have. Make sure that you always turn on your DC before you start making dust.

6" seems like overkill to me. 4" will provide you a lot better suction to get those heavier particles moving.
At least that's what I think after using 4" PVC for over 10 years.


----------

