Brad Sondahl on tue 26 jun 12
I feel particularly foolish overfiring two kilns in 3 weeks. Partly
it was my thinking lightning wouldn't strike twice, when I left a
glaze kiln firing to go to a potter's meeting and returned a little
later than I planned to find the kilnsitter contacts welded on
again... This second kiln was already destined to be replaced (this
week when I do the 6 hour drive to Seattle to get two new kilns), and
had the same symptoms as the first one-- the kiln wouldn't immediately
go on when pushing in the button, but required some hard pokes to get
it to go on and stay on. If your kiln is doing this, I highly
recommend you replace the whole porcelain block with the contacts
before you fry your kiln...
I'm switching to digital controllers, although I'm aware they don't
have a perfect track record either, and I'm afraid they might be
tougher to service myself (6 hour drive to Seattle for service)...
Brad Sondahl
sondahl.com
Steve Mills on wed 27 jun 12
Brad,=3D20
I would still keep the sitters in use; an occasional "Contacts" service wit=
h=3D
an automotive points file is all that's needed, cheaper and quicker than a=
d=3D
rive to Seattle!
I'm not saying don't go digital; I use both. The firing regime is controlle=
d=3D
by the program, and the kiln is hut off by the cone in the sitter. In addi=
t=3D
ion I always program the controller to shut off at a slightly higher temper=
a=3D
ture than the cone as a sort-of fail-safe.=3D20
Steve M
Steve Mills
Bath
UK
www.mudslinger.me.uk
Sent from my iPod
On 27 Jun 2012, at 03:30, Brad Sondahl wrote:
> I feel particularly foolish overfiring two kilns in 3 weeks. Partly
> it was my thinking lightning wouldn't strike twice, when I left a
> glaze kiln firing to go to a potter's meeting and returned a little
> later than I planned to find the kilnsitter contacts welded on
> again... This second kiln was already destined to be replaced (this
> week when I do the 6 hour drive to Seattle to get two new kilns), and
> had the same symptoms as the first one-- the kiln wouldn't immediately
> go on when pushing in the button, but required some hard pokes to get
> it to go on and stay on. If your kiln is doing this, I highly
> recommend you replace the whole porcelain block with the contacts
> before you fry your kiln...
> I'm switching to digital controllers, although I'm aware they don't
> have a perfect track record either, and I'm afraid they might be
> tougher to service myself (6 hour drive to Seattle for service)...
> Brad Sondahl
> sondahl.com
Arnold Howard on wed 27 jun 12
On 6/26/2012 9:30 PM, Brad Sondahl wrote:
This second kiln was already destined to be replaced (this
> week when I do the 6 hour drive to Seattle to get two new kilns), and
> had the same symptoms as the first one-- the kiln wouldn't immediately
> go on when pushing in the button, but required some hard pokes to get
> it to go on and stay on.
Brad, a suggestion: The kiln switches should be turned off when you
press the Kiln Sitter plunger. If pressing the plunger turns on the
power, the electrical arcing will degrade the Kiln Sitter contacts.
Something in the switch box may be interfering with the Kiln Sitter
plunger, or the locking slide may be rusty or dirty.
Sincerely,
Arnold Howard
Paragon Industries, L.P., Mesquite, Texas USA
ahoward@paragonweb.com / www.paragonweb.com
Arnold Howard on wed 27 jun 12
On 6/27/2012 4:11 AM, Steve Mills wrote:
> Brad, I would still keep the sitters in use; an occasional "Contacts"
> service with an automotive points file is all that's needed, cheaper
> and quicker than a drive to Seattle!
The coating on the Kiln Sitter contacts is delicate. Suggestion: Use a
pencil eraser to clean the contacts.
Sincerely,
Arnold Howard
Paragon Industries, L.P., Mesquite, Texas USA
ahoward@paragonweb.com / www.paragonweb.com
Taylor Hendrix on wed 27 jun 12
When I took apart my first kiln sitter, I noticed some arc pitting on the
four contact disks of the porcelain plunger. I used an eraser as Arnold
suggests because I noticed that there was a thin silver coating to the
contacts. Emory paper may even be too rough, but I've used it for tenacious
carbon deposits. Find a usable PEN eraser, the ones with a bit more grit in
them, to clean those contacts.
The cam that holds the plunger in fits right agains the inside of the
faceplate, so if the box was very dirty on the inside, checking that no
debris is binding that cam is a good idea. Also, the small wire spring that
actuates that cam is such a wee delicate thing, it bears examination as
well.
After my first solo kiln, complete with sparking contact block, I no longer
have switches on when depressing the setter's plunger. I don't even have
the breaker on.
Taylor, in Rockport TX
wirerabbit1 on Skype (-0600 UTC)
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On Wed, Jun 27, 2012 at 8:08 AM, Arnold Howard wrot=
e:
> On 6/27/2012 4:11 AM, Steve Mills wrote:
>
>> Brad, I would still keep the sitters in use; an occasional "Contacts"
>> service with an automotive points file is all that's needed, cheaper
>> and quicker than a drive to Seattle!
>>
>
> The coating on the Kiln Sitter contacts is delicate. Suggestion: Use a
> pencil eraser to clean the contacts.
>
>
> Sincerely,
>
> Arnold Howard
> Paragon Industries, L.P., Mesquite, Texas USA
> ahoward@paragonweb.com / www.paragonweb.com
>
Steve Mills on wed 27 jun 12
Which is why the power switch on the wall is the LAST thing I switch on!
I rest my case!
Steve M
Steve Mills
Bath
UK
www.mudslinger.me.uk
Sent from my iPod
On 27 Jun 2012, at 14:07, Arnold Howard wrote:
>
> Brad, a suggestion: The kiln switches should be turned off when you
> press the Kiln Sitter plunger. If pressing the plunger turns on the
> power, the electrical arcing will degrade the Kiln Sitter contacts.
>
> Something in the switch box may be interfering with the Kiln Sitter
> plunger, or the locking slide may be rusty or dirty.
>
> Sincerely,
>
> Arnold Howard
> Paragon Industries, L.P., Mesquite, Texas USA
> ahoward@paragonweb.com / www.paragonweb.com
Steve Mills on wed 27 jun 12
Point taken!
However if they're already degraded, a points file (or 400 grade wet & dry)=
=3D
is the best option.=3D20
Anything else is too coarse.=3D20
Steve M
Steve Mills
Bath
UK
www.mudslinger.me.uk
Sent from my iPod
On 27 Jun 2012, at 14:08, Arnold Howard wrote:
> On 6/27/2012 4:11 AM, Steve Mills wrote:
>> Brad, I would still keep the sitters in use; an occasional "Contacts"
>> service with an automotive points file is all that's needed, cheaper
>> and quicker than a drive to Seattle!
>=3D20
> The coating on the Kiln Sitter contacts is delicate. Suggestion: Use a
> pencil eraser to clean the contacts.
>=3D20
> Sincerely,
>=3D20
> Arnold Howard
> Paragon Industries, L.P., Mesquite, Texas USA
> ahoward@paragonweb.com / www.paragonweb.com
Gerholdclay on thu 28 jun 12
Sounds like you need to file the points. Just did that on my kiln and work=
s=3D
better.
Paul
Sent from my iPad
On Jun 26, 2012, at 10:30 PM, Brad Sondahl wrote:
> I feel particularly foolish overfiring two kilns in 3 weeks. Partly
> it was my thinking lightning wouldn't strike twice, when I left a
> glaze kiln firing to go to a potter's meeting and returned a little
> later than I planned to find the kilnsitter contacts welded on
> again... This second kiln was already destined to be replaced (this
> week when I do the 6 hour drive to Seattle to get two new kilns), and
> had the same symptoms as the first one-- the kiln wouldn't immediately
> go on when pushing in the button, but required some hard pokes to get
> it to go on and stay on. If your kiln is doing this, I highly
> recommend you replace the whole porcelain block with the contacts
> before you fry your kiln...
> I'm switching to digital controllers, although I'm aware they don't
> have a perfect track record either, and I'm afraid they might be
> tougher to service myself (6 hour drive to Seattle for service)...
> Brad Sondahl
> sondahl.com
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