# Static Electricty and the Saw Dust Collection System



## sreilly (May 22, 2018)

This is something that has bothered me for quite some time. I bought and installed a great system, the Clear Vue Cyclone CV1800, which does a great job collecting and separating the saw dust from my shop. I didn't want to spend the $$$$ for the metal duct although I know it is a better product but not sure worth that much more so I used the 6" PVC pipe and fittings making sure to use the wyes and long radius ells or 2 - 45 degree ells with a short straight piece between them.

I limited the flex hose to as short as possible and when used as tight as possible (stretched out) same as you would with flex duct in a home HVAC system. This has worked well but I always noticed that the arm hair would raise up anytime I got near a running tool while the DC was on. Lately the wire coil in the flex would sometimes reach out and zap me. The end cut on the flex was pealing back on the hose covering the end...

So after watching a video on grounding the system, actually more than a few videos, I set out to remedy the problem. At 1st I looked for bare copper wire at Lowe's and ended up with 2 reels of insulated green coated wire 14 gauge. I figured I could strip back the connection points but really wanted twisted bare copper and later found this 18 gauge wire that I really wanted to use. Smaller gauge but a better choice. The 250' spool was more then enough and proved easier to crimp on the 18 gauge ring terminals. Instead of a ring at each end on each section I doubled the wire ends (2 in each terminal) except for the 1st and last. Hope that makes sense. 

I drilled the screw holes where the ground wire attached using screws that just cleared the fittings leaving just the tip inside the pipe and countersunk the holes just enough to have that exposed tip. Take a fitting and scrap piece of pipe to determine this depth. I wrapped the wire around the pipe in maybe 6-8" intervals as I worked down the straight pipe using blue tape every now and then to keep it tight til I made the next connection. Each section that connected to a fitting or another pipe was drilled, countersunk, and screwed with a terminal. 

It may have been overkill but the fittings had the two connectors drilled and wired as did both sides of the blast gates. In the case of the flex hose I peeled back the cut end that attached to the PVC pipe or blast gate and used a butt connector crimped to the hose wire and bare copper wire. I went all the way back to the PVC connection on the CV1800 and then ran it down the wall to a near wall outlet and tied into the ground on the outlet. Yes, I am comfortable with electrical wiring as I did a great deal of both line voltage and control wiring in my past HVAC life. In old houses with copper/steel water lines you could easily attach a ground clamp and ground at that point. 

After several hours of wiring I ran the planner, the worst offender, and tested the system. Not a hair raised on my arm much less a spark to shock me. I have one run off line going to the band saw that needs tying in that I'll get to this evening and the system will be complete. To test the wiring you can rig you continuity meter to test the full wiring from start to finish to be sure there are no breaks in the wiring. 

Note on the main line there is a transition that was installed to clear the door that opened inward. That door has been replaced with an active double door that opens outwards so the transition is no longer needed. I may redo that at some point if it proves to be helpful. The minimum straight line to the cyclone is there now that ensures low turbulence thus it separates the saw dust as expected.


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## Chuck N (Feb 21, 2021)

Thanks for the details! I'm just getting started setting up my system and also chose the pvc/drain piping. Wasn't even sure if grounding was essential with the plastic/ static cause I've read from some it isn't crucial to ground plastic systems. Not taking any chances! Great idea grounding in outlet. Thanks, Chuck N


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## RainMan 2.0 (May 6, 2014)

Thanks for the info. I have the exact same system and have had a chance to install it yet . I was wondering about grounding also, as I was going to use the same pipe as you .
I thought the wire was supposed be on the inside of the pipe for some reason ,but sounds like you have it figured out


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## woodworker47 (Dec 19, 2008)

I have the same set up. Mine is plastic 4” pipe with ground wire. When I first installed, I did also run a wire on both outside and inside. After getting clogs, I finally removed the wire from the inside. Have not had clogs since.


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## MYB506 (Dec 5, 2012)

My first dust collection system was a 1 hp unit and I ran 4" plastic pipe and ran bare copper wire inside the pipe. I drilled a hole at each end of the pipe and pulled the wire tight. I never had any clogging. It also had a hard time keeping up with the planner shavings. I replaced that a few years ago with 6" HVAC pipe when I got a 2HP blower and this made a big difference.


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## Blinky (Jan 25, 2015)

sreilly said:


> This is something that has bothered me for quite some time. I bought and installed a great system, the Clear Vue Cyclone CV1800, which does a great job collecting and separating the saw dust from my shop. I didn't want to spend the $$$$ for the metal duct although I know it is a better product but not sure worth that much more so I used the 6" PVC pipe and fittings making sure to use the wyes and long radius ells or 2 - 45 degree ells with a short straight piece between them.
> 
> I limited the flex hose to as short as possible and when used as tight as possible (stretched out) same as you would with flex duct in a home HVAC system. This has worked well but I always noticed that the arm hair would raise up anytime I got near a running tool while the DC was on. Lately the wire coil in the flex would sometimes reach out and zap me. The end cut on the flex was pealing back on the hose covering the end...
> 
> ...





sreilly said:


> This is something that has bothered me for quite some time. I bought and installed a great system, the Clear Vue Cyclone CV1800, which does a great job collecting and separating the saw dust from my shop. I didn't want to spend the $$$$ for the metal duct although I know it is a better product but not sure worth that much more so I used the 6" PVC pipe and fittings making sure to use the wyes and long radius ells or 2 - 45 degree ells with a short straight piece between them.
> 
> I limited the flex hose to as short as possible and when used as tight as possible (stretched out) same as you would with flex duct in a home HVAC system. This has worked well but I always noticed that the arm hair would raise up anytime I got near a running tool while the DC was on. Lately the wire coil in the flex would sometimes reach out and zap me. The end cut on the flex was pealing back on the hose covering the end...
> 
> ...


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## Blinky (Jan 25, 2015)

MYB506 said:


> My first dust collection system was a 1 hp unit and I ran 4" plastic pipe and ran bare copper wire inside the pipe. I drilled a hole at each end of the pipe and pulled the wire tight. I never had any clogging. It also had a hard time keeping up with the planner shavings. I replaced that a few years ago with 6" HVAC pipe when I got a 2HP blower and this made a big difference.


From a retired electrician, it sounds to me like you did a perfect job of bonding to eliminate the static electricity build up. At present I'm using a shop vac with a couple of long hoses, but plan to install 3" pvc in the near future and will follow your plan. I'm thinking of using pvc conduit 90 degree elbows as they have a lot longer radius. The size matches (I checked) but pvc conduit is way more expensive than waste and vent pipe (?).


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## senebraskaee (Apr 29, 2012)

Just an 
FYI. PVC electrical conduit is more expensive as it contains carbon black, thus the gray color. I have found it does not hold or generate static like plumbing PVC. I have several funny stories of using plumbing pipe to extend the hose on an insulation blower hose and the HUGE sparks this generates when blowing cellulose insulation. I found this does not occur when using electrical conduit.


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## sreilly (May 22, 2018)

RainMan 2.0 said:


> Thanks for the info. I have the exact same system and have had a chance to install it yet . I was wondering about grounding also, as I was going to use the same pipe as you .
> I thought the wire was supposed be on the inside of the pipe for some reason ,but sounds like you have it figured out


I've heard of it being done that way but I would not impede the airflow in any means by putting anything inside the pipe. Air turbulence is a tricky thing which is why you want to use long radius ells, wyes and such. You also want a minimum of 5' of straight pipe leading into the unit to ensure in the incoming air is stable. So far so good.


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## sreilly (May 22, 2018)

Blinky said:


> From a retired electrician, it sounds to me like you did a perfect job of bonding to eliminate the static electricity build up. At present I'm using a shop vac with a couple of long hoses, but plan to install 3" pvc in the near future and will follow your plan. I'm thinking of using pvc conduit 90 degree elbows as they have a lot longer radius. The size matches (I checked) but pvc conduit is way more expensive than waste and vent pipe (?).


There are many versions of vent pipe. The standard HVAC metal pipe is maybe 28/30 gauge and usually uses a crimped end to insert into either a fitting or pipe. Most all of my duct on my home HVAC system is made in the shop with the standard use of round pipe on the takeoffs. The trunk line is made rectangular with sheet metal and sealed at the connections and where the edges are met. That being said I used the heavier gauged pipe and sealed all my fittings before insulating the ducts, something seldom, sealing the pipe with a sealant that is, done but I was a HVAC tech building my house using zone controls and a dual fuel system. Most customers wouldn't pay the extra costs in both labor and materials. 

But onto the answer, the metal duct made for DC systems is quit different in that it is a twist or snap fit, heavy gauge, and far better made (airtight) system. Just 2 companies that I know of before I looked at PVC. Nordfab and CarolinaAir are far different products then what you'll find at Lowe's and your local HVAC supplier. Compare costs and you'll see why the PVC is found in so many systems. Use the thinner and less quality HVAC pipe and compromise your system before even turning it on. You might well experience collapsed duct, high volume leaks, and other issues. What will cost more is doing it wrong and then having to redo it. There are some good books on installing these DC systems and it may well be worth the look before deciding on your path.


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## sreilly (May 22, 2018)

Well I managed to really get that post messed up. Somehow I got that metal piping was cheaper then PVC........old man genes kicking in I guess. As far as electrical PVC being more expensive I wasn't aware.and it being less prone to static. SDR 35 is what I used on this system. Be sure to look into the type of pipe and availability of fittings you'll need. I'm not aware of weys for electrical PVC pipe but they may exist. I alos haven't seen electrical PVC is larger sizes then 4", at least at the box stores like Lowe's or Home Depot, but again I haven't looked at electrical supply houses.


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## sreilly (May 22, 2018)

Stand correceted yet again, found up to 16" but after 4" it gets like liquid gold and seems the expensive metal pipe might be a better option yet between the two. Didn't even look for the fittings......


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## MYB506 (Dec 5, 2012)

sreilly said:


> There are many versions of vent pipe. The standard HVAC metal pipe is maybe 28/30 gauge and usually uses a crimped end to insert into either a fitting or pipe. Most all of my duct on my home HVAC system is made in the shop with the standard use of round pipe on the takeoffs. The trunk line is made rectangular with sheet metal and sealed at the connections and where the edges are met. That being said I used the heavier gauged pipe and sealed all my fittings before insulating the ducts, something seldom, sealing the pipe with a sealant that is, done but I was a HVAC tech building my house using zone controls and a dual fuel system. Most customers wouldn't pay the extra costs in both labor and materials.
> 
> But onto the answer, the metal duct made for DC systems is quit different in that it is a twist or snap fit, heavy gauge, and far better made (airtight) system. Just 2 companies that I know of before I looked at PVC. Nordfab and CarolinaAir are far different products then what you'll find at Lowe's and your local HVAC supplier. Compare costs and you'll see why the PVC is found in so many systems. Use the thinner and less quality HVAC pipe and compromise your system before even turning it on. You might well experience collapsed duct, high volume leaks, and other issues. What will cost more is doing it wrong and then having to redo it. There are some good books on installing these DC systems and it may well be worth the look before deciding on your path.


When I installed my HVAC duct I sealed all the joints with aluminum foil tape including all the seams and joints on the adjustable elbows so I know I have zero leaks on my system.


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## Blinky (Jan 25, 2015)

sreilly said:


> Well I managed to really get that post messed up. Somehow I got that metal piping was cheaper then PVC........old man genes kicking in I guess. As far as electrical PVC being more expensive I wasn't aware.and it being less prone to static. SDR 35 is what I used on this system. Be sure to look into the type of pipe and availability of fittings you'll need. I'm not aware of weys for electrical PVC pipe but they may exist. I alos haven't seen electrical PVC is larger sizes then 4", at least at the box stores like Lowe's or Home Depot, but again I haven't looked at electrical supply houses.


I was going to say conduit is made in larger sizes than 4" but I see you already discovered that. The largest I've ever had to work with was 6" and I didn't really work with it, I just ordered it for a job. Someone else had to do the work, thank goodness. As for fittings, I never saw electrical wyes either. For a dust collection system, I'd use the plumbing fittings. If you keep with schedule 40, one can mix conduit with drain and vent PVC. The color wouldn't match but that's what paint is for if you're into a cosmetic finish  .


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## jesica1122 (Feb 22, 2021)

I also have the same setup.


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## 1fizgig (Feb 11, 2018)

RainMan 2.0 said:


> Thanks for the info. I have the exact same system and have had a chance to install it yet . I was wondering about grounding also, as I was going to use the same pipe as you .
> I thought the wire was supposed be on the inside of the pipe for some reason ,but sounds like you have it figured out


Is it in storage with your insulation Rick?
😈


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## RainMan 2.0 (May 6, 2014)

1fizgig said:


> Is it in storage with your insulation Rick?
> 😈


lol , pretty much .I was going to insulate and drywall at the DC location so I could install it , then hopefully carry on with the rest .
But as usual I drank too much beer ,and it got cold out


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## old55 (Aug 11, 2013)

Welcome to the forum @jesica1122


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## nadobob (Nov 30, 2012)

sreilly said:


> pipe.


F/b


Blinky said:


> I was going to say conduit is made in larger sizes than 4" but I see you already discovered that. The largest I've ever had to work with was 6" and I didn't really work with it, I just ordered it for a job. Someone else had to do the work, thank goodness. As for fittings, I never saw electrical wyes either. For a dust collection system, I'd use the plumbing fittings. If you keep with schedule 40, one can mix conduit with drain and vent PVC. The color wouldn't match but that's what paint is for if you're into a cosmetic finish  .


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## nadobob (Nov 30, 2012)

nadobob said:


> F/b


. I used HDPE drain pipe. It’s cheaper than all, sorta spiral wound for wall stiffness and fittings are mostly the same as plumbing. 4” is the largest at the big box stores. Plumbing/Landscape wholesale houses have larger sizes. The nice thing about the fittings is that the pipe can be inserted to full depth dry. I didn’t glue my system, only locked the fittings in with short washer head screws (didn’t ground my system, no problems, but I guess you could run a continuous ground wire from fitting to fitting). I can’t hear any sucking sound at fittings but I think that wouldn’t be any big deal—-cheap air filtration! I have a 2 or 3hp Grizzly turbine a friend gave me that will suck the fuzz off a tennis ball. Had the HVAC tin knockers make me a cyclone and exhausted to the outside (unfiltered, clean) that I made a muffler that dropped the dB -10. My 220 remote starter worked fine but one of the fobs died and it was a PITA to find the fob when using different blast gates. Remade the remote with 24vac contractor, 24vac transformer a bunch of 3&4 way switches at each blast gate. Great set-up, much more likely to use DC at each tool use. That’s my system, Bob


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## old55 (Aug 11, 2013)

Welcome to the forum @nadobob


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