Dust on DC pipes question.

Quit making dust

Re: Dust on DC pipes question.

TM Stock

You're complaining when your dust collector does?

Upgrade your DC

ian neuhaus

4" pipe (or flex hose) is less than ideal when it comes to collecting fine dust at the source. It's this fine dust that settles on the piping.

So seriously, the best way to avoid dust collecting on the PVC piping is to collect it at the point of generation. Typically this will involve a 6" outlet on the machine and in the case of your table saw an overhead guard with inbuilt dust collection.

Re: Dust on DC pipes question.

Derek Cohen (in Perth, Australia)

Hi Barry

If this is new, then you have a leak(s) in your system. DCs are notoriously poor at remaining airtight. So, look for and seal the leaks. What type of filter are you using? The ideal is to vent outdoors (I wish I could but the neighbours would complain, so I open all doors and windows and flush the dust out). The overhead cleaner is really insufficient for this purpose.

Regards from Perth

Derek

Thanks.....

Barry Irby

The system is not new and neither is the dust on the pipes. The DC itself is outside and vents outdoors. the dust on the pipes has accumulated slowly over time.

The collection is less than perfect. I don't bother with collecting from the lathe except when I am sanding bowls, I bring a hose over and try to play the game of aiming the dust into the collector.

When I sander flatwork I use the shop vac with drywall bag on the Festool sander but don't use anything on my older PC Sander, but don't use it much anymore.

The major tools except for the lathe have DC connections. Except for the belt and disc sander where I use the shop vac. It is not as effective as I would like.

The fact the ambient air cleaners' filters get dirty tells me there is plenty of uncaptured dust. I generally wear a mask. I was mainly wondering if there was something I could do to let the dust collect inside the collector and filters rather than on the outside of the pipes. OR, Maybe I should add more pipes and figure someway to clean them regularly.

Re: Dust on DC pipes question.

John McGaw

If it is the entire length of the PVC pipe you are writing about, not just near joints, then it is probably a combination of plain old dust in the air settling out onto an easily-visible surface and electrostatic attraction. The first situation can be aided by collecting dust more effectively before it becomes airborne and the second can be eliminated by using thoroughly-grounded metal pipe. I don't know of any way to do the grounding trick other than using conductive pipe. Failing that, simply wiping it away when it becomes bothersome is the easiest non-solution.

Why is this a problem

Bill Tindall, E.Tn.

If dust collects on the pipe, it is coming from the air. Would it be better to leave it in the air or have it settle elsewhere?

Re: Why is this a problem

James Runchey

I had the same problem with my home-made collector,made from plans in Wood magazine. The unit worked great, but had accumulated a coating of dust on the 6"

Plastic pipe. I read somewhere about running copper wire in side the pipe to ground it, but I never tried it. I miss that outfit, had to leave it behind when we moved back to town. I don't have much room in my half of the two car garage, but I'm surviving O.K.

Re: Dust on DC pipes question.

Keith Newton

You might try something like FogX. I don't know if it would work, but it might be worth a try. Understanding the charge potential of individual atoms is above my pay grade. There recently was a promotion table set up at the gas station where I shop with spray cans of some new product that you could spray on the vehicle which would repel rain and dirt, but I don't recall the name.

Re: Why is this a problem

Barry Irby

It's not a problem other than being unsightly. Or is it? It's telling me there is "too much" dust in the air. I suppose the best thing to take from it is I need to do better at collecting the dust before it becomes airborne. The other side to that is there is an expense in that in both time and materials and space. I am short on space and don't need anything else that clutters my shop. I considered an over the blade guard and collector on my TS but passed because It's already too cluttered. I am not sure, but I don't see much dust of this size coming off the TS anyway. Or maybe I am blind to it.

Other than being unsightly I think it's harmless because it's stuck to the pipe.

I ran some foil tape inside some of the pipe and grounded it but I don't see much effect. I am concerned that running a copper wire inside the pipe will lead to clogs. Wonder if running a piece on the outside would help?

Re: Dust on DC pipes question.

Norman (Ottawa, Ont.)

I have a similar system and it does have some dust on it. Now are you referring to horizontal pipes or vertical pipes. I do get a little more on the very top surface of the horizontal runs but attribute this to some dust settling as it would on any horizontal surface. The super-thin coat on the vertical pipe runs is probably due to some electrostatic charge in the plastic which attracts dust.

I did have a ground wire run through the pipes at one point with terminals at the ends for grounding, but removed the wire. It would snag chips and dust. Have not had any issues ever and once a year I wipe down the pipes. I would not be concerned but if you want to completely eliminate it having a ground along the length of the pipe would probably do it.

Completely open to new theories about this though..

Norman

Re: Dust on DC pipes question.

Larry Clinton At Frankfort, (Central) Indiana

Try wiping down the outside of the pipes with the dryer softening cloths, you can use the ones that have been used in the dryer or new ones, another option is to pick up some Downy or generic fabric softener and spray the pipes. The fabric softener's all work by being hygroscopic, that is attracting water molecules from the air. This makes the pipe conductive enough to dissipate the static charge which attracts the dust.

Be sure to coat the entire pipe including where it connects to the dust collector, so the entire system is somewhat grounded.

Another use for the diluted Downy solution is to spray your carpets if you have a static problem. This will work for several months.

I worked as an engineer in a facility that produced electronics in addition to automotive components and electrical timers etc. We fought static electric daily. All of our plastic containers and totes were dipped in a solution of softener (we bought it in 50 gal barrels).

Re: Why is this a problem *LINK*

John McGaw

If the problem really is electrostatic charge, as would be demonstrated by dust sticking to the bottom of the pipe as well as 'settle' dust on the top, then grounding would be key to eliminating it. Metal pipe would be an expensive PITA to deal with as a retrofit and 'spotty' grounding with wire wraps and such are defeated by the insulating qualities of PVC.

There are other ways: one might wrap the pipe in foil and ground that (not the same a the traditional tin-foil hat). Easier would be one of the commercial treatments made for the purpose -- see the link below for an example but there are others around. I used a very expensive metallic aerosol back in my active electronics days for RF shielding and ESD protection and there are more on the market now than there were then and they've gotten cheaper.


Conductive Spray

Re: Why is this a problem

Dave Bair

If you eliminate the static that causes the dust to collect on the pipe, then it's going to be airborne until it's in your lungs.

Re: Dust on DC pipes question.

roger lance

This is interesting to me as this discussion illustrates how things change over time.

I'm no expert about dust collection. I have a collector that sits on a 55 gallon drum and roll it around the shop and connect it directly to a tool that I'll be using for awhile that produces a lot of dust that gets air borne.....table saw, planer, jointer, radial arm, and sanders.....no permanent piping runs.....no PVC. So, I've not paid much interest to discussions on such systems.

But, way back as I recall, running a copper wire thru such piping was the recommended norm and having that wire grounded was essential. Why??.....because static charges could produce sparking and sparking in an atmosphere of fine dust filled air could result in a boom. At least that's what was being talked about then.....and people were appropriately scared by this possibility.

That this issue did not come up must reflect a change in the culture regarding dust collection.....again, I've not followed such discussions and don't know why its no longer mentioned.

Re: Why is this a problem

John K Jordan

>>>I read somewhere about running copper wire in side the pipe to ground it, but I never tried it.

I believe a wire inside a plastic pipe will ground it, but only for a millimeter or so next to the wire (since the pipe is a very good insulator). You would have to coat the inside of the pipe with something conductive to ground it continuously.

If the dust outside is a result of attraction by static charges (caused by dust moving against the inside), you can probably eliminate most of the attraction by spraying with an antistatic spray, the same stuff people put on their chairs and rugs at office desks. It would have to be reapplied occasionally.

If the dust on the pipe is mostly on the top, it is mostly likely from settling. If on the sides and bottom as well it is from static charges.

JKJ

Re: Why is this a problem

TM Stock

Agree - not hurting anything and easily removed with a damp wipe. No dust collection system will gather all the fines...even assuming unrealistically high collection and filtration efficiency, every 55 gallon drum filled will pass enough dust to coat close to 4 square feet of ducting to 5 micron depth. If embarrassed by the dust, just note that it's part of the very high tech electrostatic fines trap system distributed across the surface of your ducting.

Also - I question the wisdom of attempting to cover the interior and exterior of plastic pipe with conductors, given that it would appear to be a dandy way to make a very large capacitor.

The myth was finally put to bed.

Rod Peterson--Ormond Beach, FL

That's all it was, the whole time. Some ignorant people or people trying to conflate a set of circumstances as being identical to another, yet wholly unconnected set of circumstances, was responsible for its propagation.

It's kind of like the "danger ripping on a radial arm saw" myth that went around about the same time. I always put that one down to users who hadn't read the directions and did something incredibly stupid.

Glad it's gone...for now.

Rod

Re: Kaboom theory.

TomD

I basically try not to get dust in the shop. But I do have collection also. Because of other stuff I do in the shop, I had to give up on really dusty projects.

That said, I have a dust collector, and one of those boxes that hangs from the ceiling and gets the fine particles out of the air. The dust collector itself will produce dust if you have it in the shop, and it isn't at least HEPA filtration. Mine uses felt bags, so it isn't hepa. I also have an airmate helmet, and a hepa vac for small tool extraction.

--------------------------------------------------

Where do we stand on the whole electro discharge from static build up threat? There used to be these stories about static discharging to water pipes or whatever, and melting them. PVC pipe with dust running through it can build up an impressive charge, and when it reaches the point where it can discharge to a ground source - Kaboom. This was a big issue for a while, and then it kinda stopped being something to worry about.

People would run wires through their system and into the electrical grounding of their electrical system. Then someone pointed out the charge was all around the pipes, so all you had to do was run aluminum tape on the outside, and I don't know... Run a band clamp around that, then ground the band clamp to the outlet. There used to be tons of discussion about this stuff. Anyway, if you want to reduce the static, you could see if grounding the pipes is worth doing.

I don't want to toot my horn here, but I have a lot of advanced knowledge about electrostatics, due to the fact that my local grocery has these shopping carts that discharge powerfully into your fingertips if you don't develop mastery in the field.

Re: Kaboom theory.

Barry Irby

My understanding is there has never been a confirmed kaboom in a home shop from any kind of dust collection grounded or not. There have been some in grain silos but not in small shops.

I was looking at my PVC pipes. The dust is fairly evenly distributed, not heavier on the top, so I think it's coated form electrostatic attraction. I have Micro switches on the blast gates that turn the system on when a gate is opened. The wires for them are wrapped around the pipes. There is about a two inch wide strip along the wires that clearly has less dust. This is low voltage wire and as far as I know its not grounded.

How about those of you that have metal piping? Do you have dust buildup on that?