SBRANFPOTS@aol.com on mon 13 may 96
I've been monitoring the recent discussion on electric raku and here is my
two cents.
I've been doing raku in electric kilns for 20 years. From my own experience
and research here is the bottom line. First of all it is important to keep
the issues and concerns as simple and focused as possible beginning with the
fact that much of what we do and are exposed to as potters is dangerous to
some degree. All we can do is either eliminate the danger by eliminating the
practice, or realize that there is going to be some danger, and do our best
to minimize it. When it comes to raku, I choose to minimize the danger.
In focusing my comments to electric kilns and raku, the fact is that under
the right circumstances you can get electrocuted by coming in contact with a
powered electric element. Case close, bottom line, that is a fact. You cannot
get shocked through the atmosphere of the kiln by simply reaching into the
kiln. There is a weak current in the air but no more so than what you would
pick up by putting your hand in front of an electrical outlet. So forget
about that. The element is an exposed electrical source of between 110 and
240 volts depending on your kiln. There is more current at the beginning and
end of the coil than in the middle. Big deal, in our situation that is
irrelevant. Forget about the path of least resistance and all that stuff, for
the human body is much more resistant that an electric element unless
conditions provide otherwise such as the body being wet or the person is
standing in water.
You are indeed taking a risk in using an electric kiln. You have to decide
how serious that risk is, how likely the danger is, and what you can do about
it. When I do electric raku I do not shut off the kiln. Shame on me. I stack
my pots away from the sides of the kiln. I am sure that the coils are intact
and that they are well seated in their groves and not falling out. I am as
careful as can be not to allow contact with the coils. My kiln is indoors
where it is not exposed to the weather thus there is never a chance of
wetness at or around myself or the kiln. Even with all my concern about
safety, I don't put all of the possible safety precautions into practice.
Here is more you can do: Wear rubber gloves under your kevlar gloves (I
presume you are wearing kevlar gloves), place rubber matting around the kiln
area to insulate yourself. The kiln shell and electricl boxes are grounded.
If you contact a coil AND are in contact with the kiln, you in effect ground
yourself. Zap, shock, likely electrocution. Be sure you are wearing clothes
and wrap the kiln in refractory fiber so you cannot come in contact with the
kiln. Turn the kiln off before you reach in. Uplug the kiln before you reach
in. Say a prayer before you reach in. How many of these precautions are
practical? You decide.
Be smart, be safe, but don't be an alarmist, don't panic. Weigh the risks and
the likelyhood of the dangers manifesting themselves. And please, let's be
practical and give accurate advice from experience or from a bona fide basis
in knowledge. Let's not pass on heresay, or something I once heard from
someone, somepace, I think, perhaps, maybe. Too much "knowledge" can be a
terrible thing!
Go ahead, make my day. I'm out on a limb.
Steve Branfman
WardBurner@aol.com on mon 13 may 96
I'm glad Steve Branfmam stuck his neck out first about Raku firing in an
electric kiln. I've been doing the same on and off since the 'mid 70's. Most
folks don't understand electricity and have an inordinate fear of those happy
little electrons. You NEED to RESPECT electricity, but fear destroys reason.
If you are afraid of electricity and don't know how or don't want to learn
how to wire an electric panel, then my suggestion is stay away from electric
kiln Raku firings.
Think about this:
Arc welding involves grounding a metal object and then bringing an
electrode near enough to the object so that a VERY INTENSE electric arc jumps
between the two causing the metal of both to melt and fuse. You are holding
on to the electrode and possibly the other piece of metal while all this is
going on. If people died all the time from doing this, there would not be any
arc welding. The voltages and amps cursing through all this is quite great.
One takes certain precautions when welding. So should electric kiln users,
but they can be used safely in different fashions.
When I said that Steve stuck his neck out first, I meant it. He will
receive criticism for endangering peoples lives. Our lives are full of
danger. A mechanized society produces gobs of lethal machines, chemicals, and
situations. One should not discount the dangers, but pushing the panic button
is many times uncalled for. I see the "ceramic fiber is death incarnate"
thread starting up again. I'll say this about that: If you make clay or
glazes without a respirator outside of a chemical protection hood, I feel you
run a greater danger to your health than from using refractory ceramic fiber
(RCF). If you sweep your studio, you are endangering your health to a greater
degree than if you use RCF. If you drive down a long gravel driveway with the
windows down, I feel you are endangering yourself more than using RCF. I bet
if they did animal studies like they do for RCF where they expose the little
critters to thousands & thousands of times actual dosages, we wouldn't be
allowed to have gravel driveways. Duct tape a hamster to the rear bumber of a
car, drive up and down the driveway 24 hours a day for months and this poor
little animal WILL develop some kind of serious lung problem. If we really
want to make our lives safer, there is one important thing we all should do;
We take an incredibly dangerous and flammable fuel, pump it into a metal
machine. Then this liquid begins exploding thousands of times a minute. These
explosions propel this metal machine at speeds up to 70 miles per hour.
Sometimes there are other metal machines coming in the opposite direction at
the same speed and they just miss each other by a couple of feet.
Unbelievable!, and it get's worse...THERE ARE PEOPLE IN THESE MACHINES!!!!
Many times these people are unrestrained.(Yikes!) A cursory knowledge of
basic physics would tell us how incredibly dangerous this is. And they're
raising the speed limit around the U.S.A.! If you really want to make your
life safer, there is one thing you could do right now that would vastly
change your odds of living a safe life........quit driving a car. The next
time you weigh the dangers of something, be realistic. Oh, and don't give
Steve a hard time unless you've dulled all you kitchen knives so no one will
get cut. :-)
Marc Ward
Ward Burner Systems
PO Box 333
Dandridge, TN 37725
423.397.2914 voice
423.397.1253 fax
wardburner@aol.com
Peter Powning on wed 15 may 96
Here here Steve Branfman.
I switched from gas fired cone 11 stoneware to firing raku in 4 electric kilns
indoors in a flame proof room 16 years ago and I'm not dead yet. Use common
sense, know how you can get electrocuted, then be sure you don't. I'm assuming
I hace brushed live elements but with rubber gloves inside Kevlar mitts and
rubber soled shoes on I've never gotten a shock. I certainly wouldn't
recommend trying that but I'd guess I'm well enough insulated even if I
mistakenly brush an element.
I'd also like to point out the folly of taking anything you read on this site
as gospel. In the case of safety or health advice use information here as a
starting point and seek out reliable, informed sources for further definitive
answers. I'll make an exception to that advice for Monona's comments.
Peter Powning
Sussex, New Brunswick
Came across an ageing snowdrift in the woods this morning in the midst of deep
spring, even though it hasn't snowed worth mentioning for weeks.
SBRANFPOTS on mon 23 mar 98
After catching some of the recent posts about raku I offer my thoughts.
Regarding raku firing previously high fired ware: My experience doing this has
resulted in some interesting glaze and surface effects. The ware, while not
de-vitrified so to speak (Ron Roy is correct, you cannot unfire a piece!) may
or may not remain water proof. The raku process will shock the piece, can
crackle the glaze, crack the pot, and can cause the ware to subsequently
"sweat" water. Raku glazed surfaces should not come in contact with food
although there is less danger if the food is dry and the pot is used
infrequently. As far as using an electric kiln for raku I do it all the time
and have been for over 20 years. I have found no undue stress on the electrics
of the kilns. The wear and tear happens to the hardware (lid, lid handle,
hinges, bricks) from rough handling and treatment. In order to pull the pots
you need to have an assistant open the lid using tongs. The lid should be
opened only wide enough to get into the kiln with tongs and lift the ware out.
The lid should then be closed immediately and gently to avoid cracking the lid
and the bricks around the top of the kiln. Avoid touching the tongs to the
walls of the kiln so you don't mar or otherwise abuse the bricks. I keep the
elements on during the process to keep the kiln hot enough in between pulling
my pots. Much has been written and commented about the threat of
electrocution. I have never heard of anyone getting injured by coming in
contact with the elements and I myself have done well in excess of 1000
firings in electric kilns. Frankly, it would be difficult to come in contact
with the elements since they are recessed into the walls of the kiln. To be
absolutely safe, you can certainly shut off the kiln in between reaching in.
If the kiln is not outside, then it must be located close to the outside to
avoid filling the room with smoke and flame. There are many ways to set
yourself up and to proceed with the technique in a safe manner. For instance
you can carry the pots to the outside and then place them in your combustible
material. I go into much more detail about firing in electric kilns in my
book Raku: A Practical Approach. I hope this helps!
Steven Branfman
The Potters Shop
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