Anti-Fatigue mats = static electricity?

[Rodney Randal]

I just installed anti-fatigue mats from Harbor Freight in the shop. A neighbor came by and was looking it over, and as he was walking around, he touched some of the tools with cast iron surfaces and he was getting shocked! I then had to try it and sure enough, sometimes a very noticeable shock when touching cast iron surfaces:eek:.

Does this make sense? The hygrometer in the shop showed about 57% humidity (don't know if it is accurate). I am wondering what will happen during the winter when the humidity is much lower!

Is there a way to ground either the tools, myself, or something else that can be done to eliminate this effect?

Has anyone else had this experience?

Thanks,
Rodney

[Kent Fitzgerald]

I have the same mats, and no problems with static. RH in my shop runs 50-60%. What kind of floor do you have? I'm wondeirng if the charge could be coming from the interaction between the mat and the floor (mine are on concrete).

As for a solution, grounding the tools won't help. Grounding yourself would be a drag (literally), and a safety hazard around machinery. You might experient with an anti-static spray, as long as it doesn't contain silicone, but in my experience the effects are temporary.

[Rodney Randal]

I have the same mats, and no problems with static. RH in my shop runs 50-60%. What kind of floor do you have? I'm wondeirng if the charge could be coming from the interaction between the mat and the floor (mine are on concrete).

As for a solution, grounding the tools won't help. Grounding yourself would be a drag (literally), and a safety hazard around machinery. You might experient with an anti-static spray, as long as it doesn't contain silicone, but in my experience the effects are temporary.
Kent,
The mats are on concrete floors, like yours. I was really surprised by this.

My wife suggested maybe an anti-static spray, but.... how long would it last, would it be slick, and yes, what does it contain...

Rodney

[Don Baer]

Take some of your wife's fabric softner and put it in a spray bottle, you can dilute it with water. Spray the matts, repeat as necessary. Believe it or not it works.

[glenn bradley]

Fabric softener with static control would be my first (and cheapest) attempt; then there's this and similar products.

http://www.instawares.com/Aeros-anti-static-spray.END096000.0.7.htm?GCID=C17378x016&KEYWORD=END096000

[Steve Clardy]

Mine are on concrete. Never been zapped:confused: :eek: :D

[Jim Dunn]

My dodge truck zaps me all the time but I've never had it in the shop or for that matter on antifatigue mats. It's old maybe that's what it's needing, the antifatigue mats.

My mats came from woodcraft and are on concrete too. Never had a problem.

[Rodney Randal]

I think that I will try the fabric softener approach... already have some, and maybe it will make the shop smell "just washed fresh" :D.

Thanks,
Rodney

[Mike Kelly]

I got a few mats from Compaq when they shut down some manufacturing operations in Houston. Fortunitely they are conductive anti-static mats so I don't have that problem. Fabric softener works best and is cheapest solution. Conductive mats are expensive when new.

[glenn bradley]

Mike, I'm jealous of your mats. I was thinking I'd order a few extra when we got some for work but . . . cha-ching!

[Cliff Rohrabacher]

Ground the mats.

[Blaine Harrison]

Note that a lot of the fabric softeners are simply a diluted, emulsified silicone. I'd think twice about spraying that around my shop if I plan to do any finishing in there. Fisheye isn't as attractive as birdseye. ;)

Blaine

[Frank Fusco]

Ground the mats.

Rubber conducts electricity? :eek:

[Matt Warfield]

Rubber conducts electricity? :eek:

All of our mats here are grounded due to working with electronics. When someone removes the ground, it's really very apparent.

Since he's generating a static charge on his mats, it's probably not a bare rubber surface. It could have a protective finish on it that is the culprit but I doubt you want to sand it off to find out. :rolleyes:

I'd recommend grounding the mat as well. You can test to see if it works by securing a conductor/wire from the mat to a suitable ground. Tape would work okay for securing the conductor as long as you have decent pressure on the conductor. If this works, then a simple bolt and washer will suffice to permanently attach the grounding strap.

The only reason grounding the mat may not work is if the surface doesn't permit current to flow across its surface - like PVC. It doesn't take much of a current flow to dissipate a static charge.

[Lee Schierer]

New mats will probably hold a charge. What you need to do is get them dirty.:D

Once you get sawdust on them the problem will most likely go away. Sprinkle some sawdust on them and then sweep it up with a broom. My bet is that the charge will be gone or at least greatly diminished.



Or you could make boooties of those dryer sheet fabric softeners and wear those in the shop for a few days. They work well to de-static face shields and safety glasses.

[Bruce Page]

Ground the mats.

An ESD mat is a different creature from your typical shop floor mat. Connecting a ground wire to a typical shop floor mat is pointless. I agree with Lee – grind some sawdust into them and you should be ok.

[Rodney Randal]

Note that a lot of the fabric softeners are simply a diluted, emulsified silicone. I'd think twice about spraying that around my shop if I plan to do any finishing in there. Fisheye isn't as attractive as birdseye. ;)

Blaine
Ohhh how I hope that you're wrong :eek:! I have already sprayed lightly with a diluted mixture of Downy and water. The good news is that it worked for eliminating the static, and it smells GOOD in the shop for a change!


I'd recommend grounding the mat as well. You can test to see if it works by securing a conductor/wire from the mat to a suitable ground. Tape would work okay for securing the conductor as long as you have decent pressure on the conductor. If this works, then a simple bolt and washer will suffice to permanently attach the grounding strap.
Matt I have installed the mats on almost the entire floor except where the machines reside - they are all interlocked. Since they are all interlocked and basically one piece, would 1 ground wire be sufficient? What would be a sufficient ground? Would I just secure the ground wire to my table saw cabinet for example?

I don't know if I would even be able to test the grounding of the mats now that I have sprayed them with the fabric softener and they aren't generating any static...:confused:.

Rodney

[Matt Warfield]

I don't know if I would even be able to test the grounding of the mats now that I have sprayed them with the fabric softener and they aren't generating any static...:confused:.

Rodney

Rodney,

If they're not generating any static now, then I wouldn't worry about it at all. By the time the fab soft wears off, Lee's suggestion will probably have happened automatically...unless you have a really good dust collection system.

[Rodney Randal]

Rodney,

If they're not generating any static now, then I wouldn't worry about it at all. By the time the fab soft wears off, Lee's suggestion will probably have happened automatically...unless you have a really good dust collection system.
My dust collection works fairly well, but there is still some that escapes, and will probably coat most of the mat surfaces sooner or later, but I am still curious about exactly how you would ground the mats.

[Matt Warfield]

That really depends on the surface material of the mat itself. If it's conductive or dissipative, simply bolting a ground strap to the corner will work fine. The other end should go to a ground point. Machinery may or may not be based on my limited electrical background. If it's 120V machine, no problem. If it's 240V, it may not have a ground back to the central ground in the electrical box.

As far as whether you need to ground one or all of your mats that are connected, it really depends on the material involved. If it's PVC based then you may not be able to ground an of the mats. That was the basis for my recommendation to securely tape a ground wire to a mat in order to test its effectiveness. It's no fun putting a hole in a mat to find out it doesn't help. :rolleyes:

[Kent Fitzgerald]

Machinery may or may not be based on my limited electrical background. If it's 120V machine, no problem. If it's 240V, it may not have a ground back to the central ground in the electrical box.

Matt, your'e confusing the neutral and grounding conductors. A 240 V circuit does not have a neutral, but it is required to have a ground. Any tool, 120 V or 240 V, that is not double insulated should be grounded.

[Steve Clardy]

New mats will probably hold a charge. What you need to do is get them dirty.:D

Once you get sawdust on them the problem will most likely go away. Sprinkle some sawdust on them and then sweep it up with a broom. My bet is that the charge will be gone or at least greatly diminished.



Or you could make boooties of those dryer sheet fabric softeners and wear those in the shop for a few days. They work well to de-static face shields and safety glasses.


The booties approach would be:cool: :cool: :cool: :D :D :D

[Dick Strauss]

Fabric softener will probably make the mats a little slick.

A simple wrist strap will solve the problem. Connect one end of a piece of raw copper wire to your machine and connect the other end to your wrist in a loose fashion.

FYI-Elastic wrist straps are routinely used in the electronics industry to prevent ESD. They work the same as a copper wire except they are more expensive and more comfortable.

[David Rose]

Steve, I can just see you wearing those static free booties around the shop! :p :D :eek: If you do that, please post pics. :rolleyes:

David


The booties approach would be:cool: :cool: :cool: :D :D :D

[Rodney Randal]

Fabric softener will probably make the mats a little slick.
The fabric softener did make them slick when they were wet, but now they are fine. There does seem to be a residue that is sticking to our shoes that when we walk inside on the wood floors, causes our shoes to sound like they are a little damp on the bottom:(. Hope this goes away.


A simple wrist strap will solve the problem. Connect one end of a piece of raw copper wire to your machine and connect the other end to your wrist in a loose fashion.

FYI-Elastic wrist straps are routinely used in the electronics industry to prevent ESD. They work the same as a copper wire except they are more expensive and more comfortable.
I wondered if those wrist straps would work, but didn't want any extraneous dangly things hanging around any spinny things, like blades :eek:!

Rodney

[David Rose]

Let's see... "2 inch spinny thing" (over 6" around), 6' wrist strap cord (72"), 300rpm on the spinny thing (5 rounds per second)... I think that you have just over 2 seconds to realize you are "connected" and rip that velcro off your arm or find your arm attached to the spinny thing! Hmmm...

David