mel jacobson on thu 28 sep 06
remember, the elements need to be polished.
use emery paper...wires and elements.
and, they must be tight.
the crimping tool used at the factory is
long handled and has a great deal of torque.
you cannot get that with a pliers.
i would solder them. then brush them with itc100.
i really don't know why more connections in kilns are
not soldered...? it seems the natural thing to do...when
the connection breaks, it is gone anyway...crimp or not.
it has to be cut out, one way or the other...
some may have thoughts on this/or help.
it seems a great many elements die at the connection, not
in the kiln.
but, the bolt/screw connectors you can buy
work fine. but, hold the connector in a visegrip
pliers and torque them tight. (don't hold them in your fingers
and use a small screw driver.)
mel
from: mel/minnetonka.mn.usa
website: http://www.visi.com/~melpots/
Clayart page link: http://www.visi.com/~melpots/clayart.html
Arnold Howard on thu 28 sep 06
From: "mel jacobson"
> but, the bolt/screw connectors you can buy
> work fine. but, hold the connector in a visegrip
> pliers and torque them tight. (don't hold them in your
> fingers
> and use a small screw driver.)
Visegrip pliers are a great idea for holding an element
connector while you tighten it. We use Visegrips at the
factory. That is also one of the most useful tools I've ever
owned.
Sincerely,
Arnold Howard
Paragon Industries, L.P., Mesquite, Texas USA
ahoward@paragonweb.com / www.paragonweb.com
Janine Roubik on thu 28 sep 06
Hello,
I always thought solder would be very bad for the kiln element connection because solder melts at such a low temperature. The feeder wires and connectors and pigtails are holding a heck of a lot of electricity and are getting way hotter than regular lead solder could handle.
That was what I thought, but as always, could be wrong
When something is wrong with my kiln, it is usually the connection. But now I think I have a bad switch so that should be a fun learning experience...
Janine
mel jacobson wrote:
remember, the elements need to be polished.
use emery paper...wires and elements.
and, they must be tight.
the crimping tool used at the factory is
long handled and has a great deal of torque.
you cannot get that with a pliers.
i would solder them. then brush them with itc100.
i really don't know why more connections in kilns are
not soldered...? it seems the natural thing to do...when
the connection breaks, it is gone anyway...crimp or not.
it has to be cut out, one way or the other...
some may have thoughts on this/or help.
it seems a great many elements die at the connection, not
in the kiln.
but, the bolt/screw connectors you can buy
work fine. but, hold the connector in a visegrip
pliers and torque them tight. (don't hold them in your fingers
and use a small screw driver.)
mel
from: mel/minnetonka.mn.usa
website: http://www.visi.com/~melpots/
Clayart page link: http://www.visi.com/~melpots/clayart.html
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William & Susan Schran User on thu 28 sep 06
On 9/28/06 1:22 PM, "mel jacobson" wrote:
> i would solder them. then brush them with itc100.
> i really don't know why more connections in kilns are
> not soldered...? it seems the natural thing to do...when
> the connection breaks, it is gone anyway...crimp or not.
> it has to be cut out, one way or the other...
> some may have thoughts on this/or help.
> it seems a great many elements die at the connection, not
> in the kiln.
I've seen lots of different connection methods, crimps, split bolt, barrel
connector and more, but the simplest connection that seems to work well is
used by L&L. Element pig tail wrapped around a stainless steel bolt along
with lead wires attached by ring terminal, couple of washers and the nut.
Have worked with L&L kilns since the 1970's and have never had a element
connection burn/short out. Occasionally have had to replace lead wires and
the ring terminal connectors, but very rarely.
As Mel wrote, all connections tight, tight, tight!
-- William "Bill" Schran
Fredericksburg, Virginia
wschran@cox.net
wschran@nvcc.edu
Fred Parker on fri 29 sep 06
Hi Mel:
Most soldering alloys melt well below the normal operating temperature of
kiln elements. Mechanical crimping yields the best long-term electrical
connection under these circumstances.
Fred Parker
On Thu, 28 Sep 2006 12:22:18 -0500, mel jacobson wrote:
>remember, the elements need to be polished.
>use emery paper...wires and elements.
>and, they must be tight.
>
>the crimping tool used at the factory is
>long handled and has a great deal of torque.
>you cannot get that with a pliers.
>
>
>i would solder them. then brush them with itc100.
>i really don't know why more connections in kilns are
>not soldered...?
John Hesselberth on mon 2 oct 06
On Sep 29, 2006, at 9:19 PM, Fred Parker wrote:
> Mechanical crimping yields the best long-term electrical
> connection under these circumstances.
Hi Fred,
I have a very different opinion. I will never again own a kiln with
crimped connectors. I have had too many of them burn out after a few
firings even when done with a decent crimping tool. There is often
too little room to get really good grip and leverage on the tool in
the close confines of a kiln control box. In addition you need the
strength of a gorilla even if you can get a good grip and have a long
handled crimping tool.
Threaded post and nut connectors (like L&L uses) or split bolt
connectors are what I like best.
Regards,
John
Vince Pitelka on tue 3 oct 06
John Hesselberth wrote:
> I have a very different opinion. I will never again own a kiln with
> crimped connectors. I have had too many of them burn out after a few
> firings even when done with a decent crimping tool. There is often
> too little room to get really good grip and leverage on the tool in
> the close confines of a kiln control box. In addition you need the
> strength of a gorilla even if you can get a good grip and have a long
> handled crimping tool.
John -
That's precisely the problem, and the reason why crimped element connections
are such a poor choice in kilns. Over the years I have fixed just about
every kind of electric kiln there is, and the ones that have a terminal
board like the L&L are by far the most trouble-free and the easiest to
maintain. Everyone has the needed tools in their toolbox to get the job
done properly. We have a full-time mechanical tech on our physical plant
staff and he's an expert electrician. He's got the big crimpers for when we
need them for specialized electrical connections on various machinery, but
very few potters have those crimpers, and the small automotive crimpers are
entirely inadequate for the kind of crimp sleeves that would be used for
connecting the power pigtails to the elements.
Split-bolt connectors work well, but then you have this heavy thing floating
free supported only by the stiffness of the element wire. I've seen them
sag and short out. The only really secure setup is the terminal board with
studs, nuts, and washers.
Incidentally, for superior stud-nut connections, it is best to have a washer
on each side of each wire - that means one below and above the looped
element wire, and then another one above the power pigtail ring terminal
before installing the nut. That really allows you to cinch down firmly on
all the wires and get a superior long-term connection. Most home
improvement centers have a section featuring specialized hardware, and you
can usually get 10-32 (standard size for those terminal boards) stainless
steel nuts and #10 stainless steel washers. The studs are brass, and will
corrode over time, but far less if the nuts and washers are stainless steel.
- Vince
Vince Pitelka
Appalachian Center for Craft, Tennessee Technological University
Smithville TN 37166, 615/597-6801 x111
vpitelka@dtccom.net, wpitelka@tntech.edu
http://iweb.tntech.edu/wpitelka/
http://www.tntech.edu/craftcenter/
Cynthia Bracker Sturm on sun 8 oct 06
I am posting this to clayart on behalf of my husband/Bracker's kiln
tech, David Sturm:
Hello all.
I read the posts from Vince and John and thought that I would chime in
on this. I have been repairing kilns now for nearly 12 years
professionally for Bracker's Good Earth Clays, and have also "fixed
just about every kind of electric kiln there is" during my tenure. I
have two separate points regarding crimp connectors.
First, I have never had an issue with crimp connectors burning out
after a couple of firings. I work on approximately 150 kilns a year
(nearly half of them use the crimp style connection) and have only seen
the connector itself burn out in a couple of cases:
1: The porcelain-insulator was not "put back" correctly, causing the
connector to get too close to the kiln's metal heat-shield - resulting
in a case-ground short.
2: The element was not pulled snug through the porcelain connector,
resulting in a element tail with too much "play". Over a short period
of time, the connection itself moved further and further into the
kiln's control box. The connector eventually found itself too close to
the kiln sitter's power connection screws, and it shorted out there.
3 - Incorrect wire was used inside the kiln when it had been repaired
(not by me). Either the wire was not rated to 220 F (108 C), or too
small of a gauge wire was used. (I have seen both). In the latter
case, the copper wire melted, and in the former case, the plastic
insulation on the wire burned. Both cases "melted" the connector.
4 - The crimp was inadequate when the connector was installed. To see
if your crimp is too loose, gently tug the connector after crimping it.
If it wiggles or comes off, it is too loose. Commonly, people are so
frustrated with the crimping process that they forget to do this. As
always A loose electrical connection is a BAD electrical connection.
5 - MOST COMMONLY. Instead of purchasing crimp connectors that were
designed for the voltage, wattage, and heat of the duty environment,
they just ran to the hardware store and got a bag of "the cheap ones".
These connectors WILL ALWAYS FAIL because they are NOT DESIGNED FOR THE
JOB. I find this quite common amongst customers who refuse to buy
elements from the kiln's manufacturer. Skutt, for example, provides
the appropriate connectors with every new element. Although I am
always a proponent of purchasing repair parts from the manufacturer of
the kiln, as long as the connectors being used are designed for the
heat and load it doesn't matter where you get them from.
Secondly, the above notwithstanding, I do agree that they can be a
real chore to crimp correctly.
The crimp too that I currently use is made for use by electricians
during residential wiring projects. I purchased it at Home Depot for
about $12.00. It is similar to the automotive-style crimper, but is
not manufactured cheaply. I have never had a problem with it.
My ultimate suggestion, if you just can't get the crimp right, don't
kill yourself over it. Convert to Paragon's barrel-style connector.
They are easy to use, easy to find, and not expensive. Make sure that
you change your porcelain insulators to the "mushroom style", or the
barrel will ground to the case.
David Sturm
tech@brackers.com
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