A shocking experience

[grego]

Not sure if this goes here but I will give it a try.
Has anyone with a bead blaster or sand blaster in a cabinet ever been shocked while using the blaster?
I was using mine last night and it was cold and dry and I kept feeling this sharp pricking feeling on my fingers that were holding onto the metal I was cleaning. I first thought it was the sand going thru the gloves and hitting my fingers but then I noticed a sharp clicking sound like when you zap someone from carpet shock. I turned off my light and continued and kept getting zapped so I unplugged the whole hood from the outlet and got zapped again when I started to blast again.
I was worried that I had a loose connection or a grounding problem but since I unplugged it from the socket I should have eliminated that, right?
So is it me or does it happen to other people or do I need to look into my electrical system in the shop?
It is a 20'x24' shop with a 100 amp panel, everything gfic and has a surge protector off the main lines. Copper ground rod installed above and beyond the standard building codes for California.

 

[cderalow]

using silica sand?

what you're experiencing is static discharge from the particle motion through air.

i forget why this causes a charged environment, but given a dry time of the year (winter) it's a likely cause.

try grounding the blast cabinet.

 

[MBfreak]

Blaster

What you are experiencing is probably an unintended application of a

Van Der Graaf generator.

The discharges you get are certainly not dangerous. If you are finicky you can apply a grounding wire between the object that you blast and the frame of the blaster.

Van Der Graaf generators have few practical applications today, outside a HV lab.
40 years ago they were quite popular for electrostatic painting plants, they were sold as an integrated SF6 insulated box that could produce 50 kV and enough current for a medium sized electrostaic paint booth. Have not seen one since late 70´s.

Best regards

Ola

 

[Charles (in GA)]

I've had the same issue with my TPtools cabinet. Grounding the cabinet to earth DOES NOT help. Possibly a static strap from your bare arm to the cabinet might help, but I haven't tried it yet. Really hurts when the spark jumps from the glove hold down ring to your arm or worse when you get your nose too close to the cabinet.

Charles

 

[homeputter]

I used to get shocked when vacuuming my patio of fine dust using my craftsman shop vacuum. I had to hold on to the wrought iron fence while vacuuming and then no shocks.
My new Festool vacuum has a grounded flexible vacuum hose and it does not shock.

Of course it is very dry in Phoenix - many times <6 % humidity.

 

[grego]

I guess I might go to Fry's and get one of those grounding straps that the computer builders use at their work table then strap it to my body somewhere to ground me out!!
I am glad it is not only me, I thought I was imagining things. The voices and the floating monkeys are real I tell you, me getting shocked really had me thinking.

 

[CrashTestDummy]

Has anyone tried grounding the part you're sand blasting to the cabinet? That's gotta be annoying.

Gene Beaird,
Pearland, Texas

 

[Buzzy]

Yes I have had this issue. It would make sense if that if the cabinet was grounded that it may help this static discharge. It does hurt. I would run a wire to a ground rod or cold water pipe and see if this fixes the issue.

 

[mrb]

i was shop vacing fine dust from MDF and was getting 2-3" long lightning bolts from me to metal (man that hurt) i then improvised a ground strap with some wire wrapped around my hand to a 1M resistor to ground and the problem was solved.

 

[Zeke]

I pulled a fiberglass boat hull out of a mold standing right at the gunnel about **** height. Got zapped real good right through my pants. Always wore a ground to the mold after that.