william schran on sun 17 apr 05
Fa wrote:>Tried firing my Olympic Torchbearer kiln today and came up against
the problem I usually come up against: it gets to about cone 7 and
either stalls or the temperature drops....The flame I get out of the
burners is at best a ten or so centimeters of blue and then all
yellow......Anybody have any suggestions?<
Fa - Very interesting that you should write this and I read it the
afternoon that I fired my "altered" Olympic gas kiln - it's a model
2327, fired with LP.
When I first got my kiln - and thank goodness I bought used at half
price - got it all hooked up and installed in a small metal shed -
all I could get was a yellow flame - no blue flame at all. The
lighter bar, which I think is now a tube, would simply leave massive
amounts of soot on the bottom of the kiln. Then the damn thing would
keep shutting down - I suspected the thermocouple, but the original
owner only fired the kiln a 1/2 dozen times.
I finally had enough. I ordered three MR-750 venturi burners from
Marc Ward. I think Axner and others also sell this burner, but I
wanted the conversation with Marc also. If you order from him, be
ready for some strong opinions about this kiln. Anyway, I had to cut
away the diagonal bracing on the kiln stand to fit the new burners. I
also removed the lighter tube and hooked the thermocouple and mini
burner to the first burner in line.
After fussing with the kiln continuing to shut itself off, I got the
heavy duty thermocouple from Marc Ward. I installed the new
thermocouple yesterday and fired up the kiln today. Started at 9am,
got to cone 6 on top at 1pm! Smooth sailing all the way. Now I gotta
see about holding this bad boy back a bit. I did lots of fiddling
with pressure and closing down the flue (2 IFB's on top) and was able
to get top and bottom temperatures fairly even. I think I can get the
eveness due to using 4" posts under the first shelves to get some
combustion space at the bottom. I didn't use a piece of shelf a
couple of inches under the flue this time, but I think I'll go back
to that next firing.
I think if you change out the burners you'll be very pleased with the results.
Bill, in Fredericksburg, VA, where the weather was sunny, low 70's
and I got a glaze firing, bisque firing, windshield repair, installed
3 outside lights, packed up pots for crystalline exchange, went
grocery shopping for the week and worked in the yard all done today.
Now I go back to teaching tomorrow so I can rest ;-)