Strong electro-static jolt from shop vac

[scott vroom]

I was vacuuming my shop floor (concrete slab) today with my Rigid shop vac with the stock plastic hose and a wide plastic attachment. My head touched the aluminum housing on a service lamp and I received a very strong and loud jolt of electricity...it freaked me out. I've got minor discomfort where the arc contacted my scalp. I've never encountered such a strong jolt from static buildup. It didn't help that I was wearing rubber Crocs (my std shop footwear) so none of the static buildup was grounding.

This is the same vac that I use for ROS dust extraction, which also is an issue with static shock although not nearly as sever as what I experienced today with the large hose and large suction tool attachment.

So now I'm paranoid to even turn on the vac without wearing some type of grounding leash (copper tape wrapped around my shoes and a connecting wire stuffed into my sock?).

Is/are there shop vacs that are designed to discharge static buildup some place other than onto the user?

[Kevin McCluney]

First off, I'm no expert in static electricity, but I've had similar experiences and here's how I dealt (successfully) with them. I had the same sort of static build-up & discharge from using a Shop Vac when the humidity was low. I solved it by attaching a small metal chain from the vac's wheeled base that dragged on the concrete floor. However, that vac had a metal container which the chain contacted, so I don't know how well this would work on an all-plastic model. I've also solved a similar issue (i.e., me getting charged) when using a belt sander in cold, dry conditions by tucking a small metal chain just inside my shoe so it could drag on the floor which prevented my building up a static charge. I use a large galvanized metal trashcan as a first stage chip separator in my dust collection set-up. It sits on a wooden base with rubber wheels, so I use the same dragging chain method to keep it discharged.

[scott vroom]

First off, I'm no expert in static electricity, but I've had similar experiences and here's how I dealt (successfully) with them. I had the same sort of static build-up & discharge from using a Shop Vac when the humidity was low. I solved it by attaching a small metal chain from the vac's wheeled base that dragged on the concrete floor. However, that vac had a metal container which the chain contacted, so I don't know how well this would work on an all-plastic model. I've also solved a similar issue (i.e., me getting charged) when using a belt sander in cold, dry conditions by tucking a small metal chain just inside my shoe so it could drag on the floor which prevented my building up a static charge. I use a large galvanized metal trashcan as a first stage chip separator in my dust collection set-up. It sits on a wooden base with rubber wheels, so I use the same dragging chain method to keep it discharged.

Thanks Kevin for the suggestions. I was thinking of ways to discharge with a leash but wasn't sure if the concrete floor would provide a sufficient ground. When I occasionally use my 4" DC hose to clean up a pile of chips on the floor, I slip on thick rubber gloves which works. I guess I could use the same gloves when vacuuming the floor with the Rigid. I've got a small red spot on my scalp from the arc...it was shocking (hardie-har-har) :)

[Lee Schierer]

Sucking sawdust through plastic hoses will generate a large static charge. Try the chain trick dragging from the hose. It should help even on concrete.

[Alan Lilly]

I just learn to expect it and choose which part of my body takes the shock. Fingertips have more nerve endings than the back of your hand.

[Jim Matthews]

I wonder if a hat would be a sufficient insulator?

Easier to keep a cap attached to the hose (as a visual reminder)
than to drag a grounding chain around.

[Bill Ryall]

I got tired of this with my stainless steel Rigid. I ran a bare stranded copper wire through the hose to and attached it to the metal drum, and another from the drum to a grounded metal outlet box.

[Justin Ludwig]

Here's a link to make yourself expert enough in understanding why you're getting zapped.

http://ed.ted.com/lessons/the-science-of-static-electricity-anuradha-bhagwat

They make vac hoses that won't build a charge. I personally don't mind a static shock. Grab some old speaker wire and strip it. Wrap it around the hose and ground it somewhere. Bazinga.

[scott vroom]

Here's a link to make yourself expert enough in understanding why you're getting zapped.

http://ed.ted.com/lessons/the-science-of-static-electricity-anuradha-bhagwat

They make vac hoses that won't build a charge. I personally don't mind a static shock. Grab some old speaker wire and strip it. Wrap it around the hose and ground it somewhere. Bazinga.

The vid points out that rubber, plastic and glass are insulators so I'm wondering why the static charge is able to pass through my plastic shop vac tube attachment into my body?

[scott vroom]

I got tired of this with my stainless steel Rigid. I ran a bare stranded copper wire through the hose to and attached it to the metal drum, and another from the drum to a grounded metal outlet box.

Bill great idea and I'd considered it, but my shop vac is mobile and follows me around the floor when I do a shop cleaning. A long wire leash in that application is unfortunately impractical.

[scott vroom]

I wonder if a hat would be a sufficient insulator?

Easier to keep a cap attached to the hose (as a visual reminder)
than to drag a grounding chain around.

Jim, it's not just the head...as a matter of fact that was the first time I zapped my head while vacuuming. More typical is a hand, bare arm or bare leg comming in contact with a conductor.

[scott vroom]

I just learn to expect it and choose which part of my body takes the shock. Fingertips have more nerve endings than the back of your hand.

My table saw acts as a sanding table. On warm days I wear nylon shorts in the shop. I can guarantee you that there's a far more sensitive area of the body than fingers (when I bump against the metal table edgewhile sanding, if you get my drift :eek:)

[scott vroom]

I'm thinking the best solution might be to wear rubber gloves when vacuuming around the shop floor. I have several pairs of fairly thick gloves that I use for chemical handling. Should provide enough insulation. Anyone else try this?

[scott vroom]

Where's Myk? I'm wondering if he has an opinion on whether static electricity could cause my shop vac to explode in flames.:D

[Bill White]

Well, the old Mississippi anti static trick is...(drum roll please)....Clothes dryer sheets. Yep. Same ones ya put in the clothes dryer to prevent static. Suck a couple through the hose and into the vac. Simple, inexpensive, and it works.
Thank you for the applause.
Bill

[Rod Sheridan]

[QUOTE=scott vroom;


Is/are there shop vacs that are designed to discharge static buildup some place other than onto the user?[/QUOTE]

Hi Scott, of course there are.

My Festool vac has a conductive hose and a ground terminal in the vacuum that the hose connects to. No static build up.

This is the same as the Nilfisk vacs we use at work.

I would expect that any vac designed for dust extraction would have that feature...........Regards, Rod.

[russell dietrich]

Has anyone tried anti-static spray (designed for use on plastics)?

[Bill Ryall]

Bill great idea and I'd considered it, but my shop vac is mobile and follows me around the floor when I do a shop cleaning. A long wire leash in that application is unfortunately impractical.

Tape it to the power cord. Use an alligator clip on the end to clip to the metal box, or change out the plug for a 3 prong plug and run the drain wire to the ground prong on the plug.

[Lee Schierer]

The vid points out that rubber, plastic and glass are insulators so I'm wondering why the static charge is able to pass through my plastic shop vac tube attachment into my body?

Static electricity is not the same as electrical current. Static electricity is a charge on the surface of an object. The object does not have to be metal nor a conductor to hold a static charge. If the charge gets high enough and is close enough to an object with less charge, a discharge can occur through the air. Run a plastic comb through dry hair and it will pick up pieces of tissue paper though neither item is a conductive material. Rub a rubber balloon on your hair and it will develop a charge and you can stick the balloon on the ceiling where it will stay until the charge dissipates. Sucking sawdust through a plastic hose is similar to the rubbing of the balloon on your hair and since you are holding the hose, your body also develops a surface charge right along with the hose but unfortunately you get to be the point of discharge when you touch a less charged object. You can safely discharge by grabbing a grounded object with your hand, not just a finger.

[scott vroom]

Thanks everyone for the education and suggested solutions. Today I donned my rubber gloves and vacuumed my shop without a single discharge. Should have thought of it earlier.

[Keith Westfall]

One can well protect themselves I suppose, but what about around the CNC or electronic tool controls? Can he static harm "them"??