search  current discussion  categories  kilns & firing - cones & controllers 

welding thermocouples

updated fri 17 oct 08

 

mel jacobson on sun 4 jan 04


we have had some luck with getting those bi/metal
thermocouples together with oxy/acet welding.
we just use a big gob of borax on the tip.
get it hot, let it turn to glass, then it sorta melts together.

this is a home remedy fix.

often, the only way to get them together, without
exotic welding equipment.
others may have other solutions.

it is amazing what our gang at `hay creek` can come up
with when pressed by need.

my first experience with bimetal technology was the old time
automatic choke. it was bimetal/ in spring form...when hot it would
uncoil, cold, it would coil. i remember showing that to kids
in class...we would use the burn-zo-matic torch , had an old
choke from the auto shop...i don't know
how that got started, but it was fun to see. also
had them hold up a piece of kaowool board and i would try
and get their hands hot on the other side. `hey mel,
burn my buddies hand` of course they would be shocked and
surprised. `wow, is that a space shuttle tile?` `yup`.
mel
i remember the day i had to explain `hemi`...the engine.
that went on for a week...all kinds of kids showed up and
got in on that discussion. drawings all over the art room.
drawing, visual language.




From:
Minnetonka, Minnesota, U.S.A.
web site: my.pclink.com/~melpots
or try: http://www.pclink.com/melpots
new/ http://www.rid-a-tick.com

iandol on tue 6 jan 04


Mel makes a good point.
Borax, Sodium Tetra Borate, makes a good flux for most gas welding and =
brazing jobs where the parts are being heated higher than about 800=BAC. =
It's a real scavenger of base metal oxides. Excellent with Type E, J, K, =
N and T thermocouples. Noble metal thermocouples can be welded this way =
if you can make their melting points. But as I said, Carbon from an Oxy =
Acetylene flame can cause embrittlement of some alloys. The Oxy Hydrogen =
flame was used without a flux.
Electric Spot welding would be another choice.
Best regards,
Ivor Lewis. Redhill, South Australia

mel jacobson on thu 16 oct 08


kurt and i have repaired several
thermocouples...emergency repair at the
farm, during a firing.

we use a oxy/ac welder/and we cover the
end that we have cleaned and twisted with
borax...a big gob.
it seems to flux and make a big glass ball
at the end.
works like a charm. the two we have repaired are
still working just great...after salt, wood and gas firing.
no ceramic tubes. we also dip the ends of all metal
pieces in itc.
mel
this is seat of the pants repair/someone else may
do the engineering, science aspects.
from minnetonka:
website http://www.visi.com/~melpots/
clayart site:
http://www.visi.com/~melpots/clayart.html