Shock from pyroceramic platen! Ouch!

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Nov 28, 1999
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I got one of those pyroceramic glass platens for my Bader BIII, and it made a huge difference in the quality of my flat grinds. Now, I dont have an excuse for a blade not being flat. Or do I? At first, I thought something had gone haywire with the wiring on my Bader, because I kept getting shocked. Evidently, these platens generate static electricity. No longer can I rest my finger on the side of my platen as a guide, because it shocks the sh#t out of me! I talked to another well known knifemaker who I knew had bought one of these pyroceramic platens, and he said that while his grinding did improve using it, he has since taken the platen off due to his getting shocked all the time. Anybody else having this problem? I will continue using mine, but will definitely be careful.
 
Yes, it will bite you pretty good at times, here's what I did to solve the problem. I took a small diameter wire (14) and ran it from the grinder to a piece of 12"- 1/2" rebar I drove into the ground. Then I took another piece of wire about 4 feet long and put a small gator clip on each end. When the static electricity gets bad I just clip one end of the short wire to the ground wire already hooked to the grinder and put the other end into my sock or under my waist band, anywhere it will be in constant contact with the skin, no more shocks.

Hope this helps

Bill
 
I have had the same problem. It will arc about an inch. What has happened is, you have insulated the platen from ground, so when the belts generate static, it builds up in the body, the only way to discharge to ground, is when a body part gets near metal on the grinder.
I was thinking of running a bead of JB weld up the side of the platen, the metal, and glass ones. It would contact the back of the belt when dry, and hopefully bleed off the static electricity, as it is full of metal particles. I don't like running ground wires to myself.:confused:
 
Where do you guys get the pyroceramic platents?
I had a similar experience with ceramic beads. I was vacuuming them out of my blast cabinet and it was lighting me up big time.
 
Yep, same thing for me. I haven't done it but have been thinking about getting one of the ground clips used by computer service techs. It has a wrist band and an aligator clip to attach to any handy ground. Do you think this would be sufficient to bleed off the static?

Michael, Steve Pryor has the platens. Here's a thread you might use to contact him. He's a great guy to deal with.

Steve Pryor

Dave
 
Originally posted by ddavelarsen
It has a wrist band and an aligator clip to attach to any handy ground. Do you think this would be sufficient to bleed off the static?
Dave

Yes, all you're doing is making yourself the same potential as the machine, which I'm SURE (and you make DAMN SURE) you have grounded electrically through the motor/power circuit. You can put one end of the grounding strap to the motor chassis, the grinder frame, etc.....as long as they are connected to each other and the other to your body, out of the way.

There is a bunch of voltage present during ESD (eletro-static discharge), up to 60,000+ volts :eek: but almost no current flow, kind of like one of those stun gun things.
 
Originally posted by B . Buxton
Yes, it will bite you pretty good at times, here's what I did to solve the problem. I took a small diameter wire (14) and ran it from the grinder to a piece of 12"- 1/2" rebar I drove into the ground. Then I took another piece of wire about 4 feet long and put a small gator clip on each end. When the static electricity gets bad I just clip one end of the short wire to the ground wire already hooked to the grinder and put the other end into my sock or under my waist band, anywhere it will be in constant contact with the skin, no more shocks.

Use one of those computer anti-static wrist straps, attach the clip to your grinder.

You should not have more than one earth ground in your house. It hooks to your main electrical service entry. Adding earth grounds to a home or shop electrical system affects computers and such, and is potentionally life threatening in certain circumstances.

AL P.
 
Personally I could see no difference glass or no. I do however seem to have more of a static problem in the winter, with the wood furnace only a couple ft. from my grinder.:eek:
Like some of the others I find that a ground wire to me helps, and on occasion just wet down the concrete floor. This adds enough humidity to keep it down for awhile.
Another thing I do is to occasionally hit the platen frame with the heel of my hand to discharge before it gets built up to skin scarring levels.
 
While I was working this morning I had quite a light show. The sparks were jumping POP,POP,POP,POP,POP,POP - pretty darn quickly. They are a pretty deep blue or purple color. But -- Ouch! Ouch! Ouch! Ouch! Ouch! Ouch!

:D

Dave
 
don't know if this'll work or not: take a small piece of aluminum foil and tape to an unused edge of the glass and wrap it around to the platen. Maybe even glue it on with JB Weld. This'll provide the necessary circuit, assuming your machine is properly grounded. I have two platens mounted with this stuff, using Zap-A-Gap, and haven't had a spark, yet. I was also wondering, I grind with alot of dips in the slack tub, and wonder if maybe the water doesn't provide the ground necessary.
 
I guess I better state something here, my grinder is a 2 pulley coote. The motor is mounted to the work bench and sets back away from the grinder it self. The only contact with the motor is through a rubber drive belt, so when I drove the ground rod, the only purpose was to ground the grinder(platen), there is no electrical circuit or motors, etc. hooked to this ground rod. All I can say is it works for me and has for about 1 1/2 yrs. If you have any doubts or worries about this type of grounding, then don't do it this way, I don't want to be the cause of anyone getting hurt or injured. :footinmou

Bill
 
Hey Dan, I have thought about your problem and decided the only way to cure it is to box that machine up and send it to me! Problem solved!:)
 
There is an easy way out on that static electricity problem. The drier the climate the more static electricity. We get some dandy light shows here were we live in the summer months at times. I found you can set up one of those fine cold water misters that are found in drug stores and that will help some, but the easy way out of this problem is simply to spray the moving belt with a little of that anti static spray that is sold for clothes. It works great and right now, and sometimes even if you takewe the belt off for awhile and then go back to use it again it will still be static free. It is cheap to use and to haqndy not to use it. Yes I have been using one of those neo ceran plates for about seven years now, and they are great. Do remember that they too will eventually develop wear spots. Frank
 
Hey Craig, I will come up and bother you soon, but I aint bringing the Bader! :)
 
"...does not conduct electricity"

-taken from the upper left corner of the back of the card to which the tubes are attached when sold.

Happened to buy some yesterday, and still have the card, which I uncharacteristically read and also uncharacteristically partially recalled.

The set-up under discussion resembles a (fortunately relatively inefficient) Van de Graff generator, depending upon what materials are employed for the sanding belt, platten, rollers, and degree of isolation from ground and nearby conductors. No big hollow metal collection ball, that's replaced by the operator :)


http://www.amasci.com/emotor/belt.html

If there are also arcs jumping onto the belt from something grounded (and probably with a sharp corner), you've got something like the "combs" discussed in the link, and the problem will likely be much worse.

Anyone who can construct their own belt sander should be able to make a killer Van de Graff generator if they wanted to.
 
Firkin, thanks for the info. I guess I will try Fitzos solution next. If that doesn't work, I'll go with the wrist ground strap.:confused: :D
 
Hey, Mike...

A different type of static:

I was thinking.... maybe with a ground strap and that metal plate in your neck you could maybe be one of those people who could pick up the local FM station?? Voices in the head could take on a whole new meaning??;) :D

I know, I know... with the fake hips, maybe I could insert a wire close to them and get the same effect....hehe.
 
I didn't know the voices came from FM radio, they acted like they knew me, and told me what to do.;) :D
 
I wonder if my voices know your voices? Perhaps they could do lunch?
:D
 
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