[Clayart] Clayart Digest, Vol 83, Issue 18

[Village Lady]

Such good points in these comments. I’ll add this:  

Kathi, you were wise to seek the advice of a different electrician and to emphasize that not all electricians are knowledgeable about kilns.  They all should (but many don’t) understand that some high-heat-duty appliances are not drawing maximum amperage the entire time they are operating and also - crucially important - that most kilns will draw enough amperage for a far longer time than a clothes dryer or cooking oven to directly affect the ability of the supply wiring (the feed to the outlet for the kiln) to dissipate heat which electrons generate while they are flowing.  The more flow (i.e. the higher the amperage) over a longer time, the more heat the wire itself has to get rid of or it will probably fail and cause a short and a fire. That heat is in addition to the heat the kiln’s elements are generating.  If an undersized feed wire is used, placed in an enclosed wall cavity, surrounded by closed cell foam of a non firerated formulation, and the kiln is placed close to the outlet and without adequate air movement … well, that is a prescription for disaster and, sadly, one experienced too often by folks who think the most important task in using a kiln is learning how to fire good pots.  Nope, the most important is learning how to keep people and property safe, then come the pots.  

As for twisting together broken elements and other fixes, if one knows as much and is as careful to monitor the kiln as Mel, then such a practice can be safe and effective.  That is a big “if”, though, in these times when so many people like to “set it and forget it” and then are unpleasantly surprised when something they did not know caused damage.  I know you folks already know this but it bears repeating:  kilns are technical equipment and require a technical level of knowledge to use them safely and effectively.   

Karen
(I’m old skool - a potter and kiln builder since the 70s)

> On Oct 15, 2022, at 8:03 AM, clayart-request at lists.clayartworld.com wrote:
> 
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> Today's Topics:
> 
>   1. Re: Kiln question (William Schran)
>   2. Re: Kiln question (kathi at lesueurclaywork.com)
>   3. old kilns a story (mel jacobson)
>   4. Re: old kilns a story (David Lyons)
> 
> 
> ----------------------------------------------------------------------
> 
> Message: 1
> Date: Fri, 14 Oct 2022 12:56:13 +0000
> From: "William Schran" <wschran at twc.com>
> To: "'Clayart international pottery discussion forum'"
>    <clayart at lists.clayartworld.com>
> Subject: Re: [Clayart] Kiln question
> Message-ID: <e4bbe2612c35ebd147d5f3181cbcac366d4c46a5 at webmail>
> Content-Type: text/plain; charset="utf-8"
> 
> As David wrote in his response, 220/240V are essentially the same
> voltage coming to residences. Only issue with used kilns from
> institutions is they may be 208V and 3 phase connection. No worries
> your home is 220/240V single phase.
> It will be important that you have the correct wiring and circuit
> breaker for your kiln. A quick look at this kiln's electric
> specifications states a 48 amp draw so this requires a 60 amp breaker
> and #6gauge copper wire for line to the 6-50P outlet. If you can
> install near the circuit breaker you can keep supply line under 40
> feet long that is needed otherwise you'll need #4 gauge wire. Make
> sure kiln location can be provided with cross draft ventilation.
> 
> William Schranwschran at twc.com703-505-1617
> 
>    -----------------------------------------From: "Ginger Dunlap-Dietz" 
> To: "Clayart international pottery discussion forum"
> Cc: 
> Sent: Thursday October 13 2022 7:08:08PM
> Subject: [Clayart] Kiln question
> 
> I've been offered for free in good condition an older Cress Firemate
> (FX27P) with 220 volts but the voltage in my new studio is 240. I'm
> wondering if it makes sense to take it and change the elements rather
> than
> buy a new kiln with a controller and sections.
> 
> I fire to Cone 6.
> 
> Thanks,
> 
> Ginger D-D
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> 
> Message: 2
> Date: Fri, 14 Oct 2022 14:36:08 -0400
> From: "kathi at lesueurclaywork.com" <kathi at lesueurclaywork.com>
> To: William Schran <wschran at twc.com>, Clayart international pottery
>    discussion forum <clayart at lists.clayartworld.com>
> Subject: Re: [Clayart] Kiln question
> Message-ID: <D310A41C-4579-4F07-8856-502533A72A54 at lesueurclaywork.com>
> Content-Type: text/plain; charset=utf-8
> 
> I would suggest if you have a local clay supplier to ask if they can recommend an electrician. Not all electricians understand kilns. I had one insist that when my computer controlled  kiln was on it was drawing 45 amps. I explained that the computer did the same thing as the switches on the kiln next to it. He told me I didn?t  know what I was talking about and BOTH drew 45 amps when on regardless of how the switch was set. He also checked the wire connections. ?Tightened them?. The next electrician tightened them more.
> 
> Kathi LeSueur
> 
> Sent from my iPad
> 
>> On Oct 14, 2022, at 2:18 PM, William Schran <wschran at twc.com> wrote:
>> 
>> ?As David wrote in his response, 220/240V are essentially the same
>> voltage coming to residences. Only issue with used kilns from
>> institutions is they may be 208V and 3 phase connection. No worries
>> your home is 220/240V single phase.
>> It will be important that you have the correct wiring and circuit
>> breaker for your kiln. A quick look at this kiln's electric
>> specifications states a 48 amp draw so this requires a 60 amp breaker
>> and #6gauge copper wire for line to the 6-50P outlet. If you can
>> install near the circuit breaker you can keep supply line under 40
>> feet long that is needed otherwise you'll need #4 gauge wire. Make
>> sure kiln location can be provided with cross draft ventilation.
>> 
>> William Schranwschran at twc.com703-505-1617
>> 
>>   -----------------------------------------From: "Ginger Dunlap-Dietz" 
>> To: "Clayart international pottery discussion forum"
>> Cc: 
>> Sent: Thursday October 13 2022 7:08:08PM
>> Subject: [Clayart] Kiln question
>> 
>> I've been offered for free in good condition an older Cress Firemate
>> (FX27P) with 220 volts but the voltage in my new studio is 240. I'm
>> wondering if it makes sense to take it and change the elements rather
>> than
>> buy a new kiln with a controller and sections.
>> 
>> I fire to Cone 6.
>> 
>> Thanks,
>> 
>> Ginger D-D
>> -------------- next part --------------
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>> URL: <https://lists.clayartworld.com/pipermail/clayart/attachments/20221014/21b7824a/attachment.htm>
> 
> 
> 
> ------------------------------
> 
> Message: 3
> Date: Sat, 15 Oct 2022 00:48:56 +0200
> From: mel jacobson <melpots at mail.com>
> To: clay art <clayart at lists.clayartworld.com>
> Subject: [Clayart] old kilns a story
> Message-ID:
>    <trinity-060cff6f-97c1-4d44-a8a0-5ada0f7bf4c4-1665787736522 at 3c-app-mailcom-lxa01>
>    
> Content-Type: text/plain; charset=UTF-8
> 
> there are many old kilns out there that can be used
> for years to come. knowing basic specs like "phase" etc
> are critical, and knowing the amperage. it all has to match.
> distance as Bill has mentioned is critical. if you can, keep the
> kiln near the breaker box.
> 
> I do not patch in electrical systems for folks.  far to dangerous.
> I do it for me, but not others.
> 
> we got an old electric kiln a few years back for the farm. 40 amp, worked
> fine with a dryer cord and plug. just a few feet from our garage breaker box.
> it is a "blue diamond", from florida some place. runs with springs to auto
> fire the kiln.  the springs are too tight and the kiln gets far too hot, too fast.
> I start the kiln, then turn it off, start again, then again. when it hits 500 I
> just let it go. we only bisque fire in it.
> 
> I did not change coils, just cleaned it, polished all the connections and let her
> rip. the entire project of install and firing cost us nothing. about 20 years ago
> I bought of box of about 50 kiln coils.  all new. left over from a college program.
> 50 bucks donated to their clay fund.  in a pinch, any one of those coils could be
> added to this kiln. it will get hot, I just don't worry about the specs.  one coil.
> I bend coils using a bernzomatic gas torch. turn red, bend. a small set of pliers
> and away we go. polish all connections, make a tight connection.  works great.
> 
> I even tie coils together when they break in the kiln.  all one has to do is heat
> the break to red hot, grab the ends and pull them out. sand paper each end, or as I do,
> use a tiny power grinder.  make them clean and bright...grab both ends, heat to red
> and twist the two wires together. and then push them into the groove. (yes, use pliers, not
> your fingers.)
> 
> I did the twist together coils with an old L&L kiln I got at the dump. After the twist
> fix, I got 38 firings to bisque temp in that kiln. The control box finally rotted out
> and was falling off.  I sent a picture to Steve Lewicky the owner of L&L and demanded
> a new kiln as mine was falling apart. he sure laughed.  that kiln was build by his
> dad in 1968.
> 
> the big issue is, if you only bisque fire in an electric kiln, take your time and do it
> right...it will last for years without new coils.  cone 9 in an electric kiln will be
> a quick murder of the kiln. WHY DO WE LOVE RON AND JOHN.?  CONE 6, AMAZING POTS AND
> GLAZES. think of the kilns they have saved.
> 
> just remember what carol marions has taught us. down fire. it works for you too. cone 6,
> turn off kiln, then back on for two hours, let it cool, turn it back on at 1700 for
> for more hours. see what happens. of course she is a world class expert in silica
> and melt, but you can take her system and make it work for you. down firing is not
> expensive, one switch on, hold temp. or program it like bill schran does for crystal
> glazes. it works.  carol shows you the way...follow her, it is why she does it for
> clayart....shared knowledge.  she wants you to grow and learn. then it becomes your own voice.
> 
> I will give you any recipe I have...but you cannot have my pots without using my clay and
> my firing timing. that is the hard part.  anyone can copy a recipe...but, can you make
> great pots.???? clay body may be the most important part of making "clay" objects fired
> in a kiln.
> mel
> 
> 
> website: www.melpots.com
> www.melpots.com/CLAYART.HTML
> 
> 
> 
> ------------------------------
> 
> Message: 4
> Date: Fri, 14 Oct 2022 18:31:34 -0500
> From: David Lyons <lyonsd at plbb.us>
> To: Clayart international pottery discussion forum
>    <clayart at lists.clayartworld.com>
> Subject: Re: [Clayart] old kilns a story
> Message-ID: <53481875-5B4F-489D-9947-C1AC92070628 at plbb.us>
> Content-Type: text/plain; charset=utf-8
> 
> I have a Duncan kiln that I am turning off and on like Mel describes. Otherwise it fires way too fast.  Is this the same situation in Mel?s kiln with springs and is there an adjustment to slow the firing down?
> Dave Lyons
> 
> Sent from my iPhone
> 
>> On Oct 14, 2022, at 5:54 PM, mel jacobson <melpots at mail.com> wrote:
>> 
>> ?there are many old kilns out there that can be used
>> for years to come. knowing basic specs like "phase" etc
>> are critical, and knowing the amperage. it all has to match.
>> distance as Bill has mentioned is critical. if you can, keep the
>> kiln near the breaker box.
>> 
>> I do not patch in electrical systems for folks.  far to dangerous.
>> I do it for me, but not others.
>> 
>> we got an old electric kiln a few years back for the farm. 40 amp, worked
>> fine with a dryer cord and plug. just a few feet from our garage breaker box.
>> it is a "blue diamond", from florida some place. runs with springs to auto
>> fire the kiln.  the springs are too tight and the kiln gets far too hot, too fast.
>> I start the kiln, then turn it off, start again, then again. when it hits 500 I
>> just let it go. we only bisque fire in it.
>> 
>> I did not change coils, just cleaned it, polished all the connections and let her
>> rip. the entire project of install and firing cost us nothing. about 20 years ago
>> I bought of box of about 50 kiln coils.  all new. left over from a college program.
>> 50 bucks donated to their clay fund.  in a pinch, any one of those coils could be
>> added to this kiln. it will get hot, I just don't worry about the specs.  one coil.
>> I bend coils using a bernzomatic gas torch. turn red, bend. a small set of pliers
>> and away we go. polish all connections, make a tight connection.  works great.
>> 
>> I even tie coils together when they break in the kiln.  all one has to do is heat
>> the break to red hot, grab the ends and pull them out. sand paper each end, or as I do,
>> use a tiny power grinder.  make them clean and bright...grab both ends, heat to red
>> and twist the two wires together. and then push them into the groove. (yes, use pliers, not
>> your fingers.)
>> 
>> I did the twist together coils with an old L&L kiln I got at the dump. After the twist
>> fix, I got 38 firings to bisque temp in that kiln. The control box finally rotted out
>> and was falling off.  I sent a picture to Steve Lewicky the owner of L&L and demanded
>> a new kiln as mine was falling apart. he sure laughed.  that kiln was build by his
>> dad in 1968.
>> 
>> the big issue is, if you only bisque fire in an electric kiln, take your time and do it
>> right...it will last for years without new coils.  cone 9 in an electric kiln will be
>> a quick murder of the kiln. WHY DO WE LOVE RON AND JOHN.?  CONE 6, AMAZING POTS AND
>> GLAZES. think of the kilns they have saved.
>> 
>> just remember what carol marions has taught us. down fire. it works for you too. cone 6,
>> turn off kiln, then back on for two hours, let it cool, turn it back on at 1700 for
>> for more hours. see what happens. of course she is a world class expert in silica
>> and melt, but you can take her system and make it work for you. down firing is not
>> expensive, one switch on, hold temp. or program it like bill schran does for crystal
>> glazes. it works.  carol shows you the way...follow her, it is why she does it for
>> clayart....shared knowledge.  she wants you to grow and learn. then it becomes your own voice.
>> 
>> I will give you any recipe I have...but you cannot have my pots without using my clay and
>> my firing timing. that is the hard part.  anyone can copy a recipe...but, can you make
>> great pots.???? clay body may be the most important part of making "clay" objects fired
>> in a kiln.
>> mel
>> 
>> 
>> website: www.melpots.com
>> www.melpots.com/CLAYART.HTML
>> 
> 
> 
> 
> End of Clayart Digest, Vol 83, Issue 18
> ***************************************