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It is common in woodworking (A hobby of mine) to make a dust collection system (Basically a tube hooked up to a vacuum to carry away dust created from automatic woodworking tools) out of PVC.

We'll assume that we're using a PVC dust collection system (I'm aware that we could sidestep the issue by insisting that we use a conductor)

Dust Collection

Apparently, due to the physics-chemistry of rubbing PVC, this develops a large static charge.

Solutions to this problem include running a bare copper wire around the outside, inside, or some combination of both. (Similar to https://www.youtube.com/watch?v=XtkHzmXe4ZA)

My question is: What solution is optimal, and are certain solution invalid or wishful thinking?

PVC is an insulator, meaning (In the traditional charge model) that charge cannot move through regions of the PVC and is not guaranteed to be distributed equally.

Is grounding on the outside of the PVC useless since this isn't where the charge builds? Is screwing into the inside of the tube not helpful since charge can't move to the grounded screw?

What is the optimal way to ground a PVC dust collection system?

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What is the optimal way to ground a PVC dust collection system?

You CANNOT ground a PVC pipe. Charge WILL accumulate on both the interior and exterior surface.

You can reduce the accumulation of charge by:

  1. Running a wire inside the pipe to reduce internal charge buildup.
  2. Running a wire outside the pipe to reduce external charge buildup.
  3. Increase the humidify of air in the pipe.
  4. Introduce ionized air to the pipes (this is used heavily in the manufacture of plastic pipe where charges can be dangerous)
  5. Introduce some conductive coating to the pipe (Y-Shield makes a conductive and RF shileding paint, but it's expensive)

Ideally, DON'T use PVC pipe for extractors unless it's manufacvtured to be anti-static ...but since you already seem have used a non-antistatic pipe you need to control the static buildup.

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  • \$\begingroup\$ I actually have neither a dust collector nor a PVC system yet. I'm in the design phase for the system and am exploring options. That picture is from DDG. Would you care to involve more of a physical context though. It appears that you've just asserted what happens rather than give an explanation for why it happens. \$\endgroup\$ – Sarah Szabo Mar 29 at 2:06
  • \$\begingroup\$ In this case why it happens is fast moving air over a highly insulated surface. Read any details on why static accumulates on varies surface. You didn't ask why in your question. \$\endgroup\$ – Jack Creasey Mar 29 at 2:55

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