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oxy-probe life expectancy?

updated sat 19 aug 00

 

Garret D. Bonnema on wed 16 aug 00


I am having to have our oxy-probe practically rebuilt after three years of
use, which will be close to 2/3 the cost of a new one. I am wondering if
anyone on the list has experience with how long these probes last before
they need serious $$ repairs. Mel, in a recent posting, mentioned that he
sends his back for repair about every two years.

We have used ours for less than three years. In that time I have fired about
47 glaze loads and maybe 30 bisque loads. The probe was placed so as not to
get hit, and was left in place, not moved for the whole time.

Is our experience within the norm.
Thanks,
Garret Bonnema
Bethel, Maine

WHC228@AOL.COM on wed 16 aug 00


Garrett
Usually repairing an oxyprobe isn't a big deal. I just get some thermocouple
wire and replace the part that has gone bad. I have gotten wire from both
Cleveland Electric Labs in Cleveland and Kieth kiln company in California.
The wire is sold by the ounce and is priced as the metal market changes daily.
Platinum/rhodium usually lasts a long time if it isn't in a hostile
atmosphere. It doesn't like High zinc atmospheres.
Bailey sells a protection tube that seems to help some.
I not gotten any new wire for mine because I bought enough to make several
repairs the last time that I got some. I mention that because I can't
remember if it uses S type wire or R type wire.
If the problem is on the inside of the couple I just replace it with a new
one.
Do not throw away the wire. It can be sent in and you will bet credit for the
metal. The metal is what makes it so expensive.
Good luck.
Bill Campbell

Jonathan Kaplan on wed 16 aug 00


I purchased our AIC probe from Nils in the early 1980's. After an
"accident" soon thereafter, the probe was rebuilt and has been functioning
very well since then. I do need to replace the thermocouple wire now as the
temperature numbers are eratic. It sits safely in the roof of our kiln in a
protective tube with about 3/4" of the probe protruding into the chamber.

We have 250 firings on this kiln with this probe, and if my senior moment
memory serves me correctly, 350 or so on my previous kiln. So I think thats
pretty damn good!

Jonathan

Jonathan Kaplan
Ceramic Design Group LTd/Production Services
PO Box 775112
Steamboat Springs, CO 80477
(970) 879-9139 voice and fax
http://www.sni.net/ceramicdesign

UPS: 1280 13th St. Unit13
Steamboat Springs, CO 80487

Hank Murrow on fri 18 aug 00


>Garret Bonnema wrote:
>I am having to have our oxy-probe practically rebuilt after three years of
>use, which will be close to 2/3 the cost of a new one. I am wondering if
>anyone on the list has experience with how long these probes last before
>they need serious $$ repairs. Mel, in a recent posting, mentioned that he
>sends his back for repair about every two years.
>We have used ours for less than three years. In that time I have fired about
>47 glaze loads and maybe 30 bisque loads. The probe was placed so as not to
>get hit, and was left in place, not moved for the whole time.
>
>Is our experience within the norm.

I have supplied The AIC OxyProbes and now the Axner units on my Doorless
Fiber Kilns and have had only two failures due to the early units having no
protective tube installed. The reduction atmosphere seems to harden the
platinum ground wire which returns alongside the thermocouple tube. Once
Nils suggested the installation of a 1/2" protection tube, the troubles
disappeared. The instrument longest in service has 1240 fires on it. I
always recommend yearly maintenance(removing the wire connections and
cleaning with very fine emery, and inspection of the probe end for damage.
BTW, Nils has been extremely cooperative and responsive with regard to repairs.
Hank in Eugene