[Clayart] Geil kilns

[ka...@lesueurclaywork.com]

A friend bought a Geil kiln from a potter who was retiring. It’s a fiber kiln with six Venturi burners. Three on each side. This kiln has been a nightmare for her. It fires unevenly in both temperature and reduction. She says the only control she has is from the damper. She can’t adjust the air coming in at the Venturi burners.

Anyone have this kiln. If so, how do you create an even firing and reduction. Right now she considers this a very expensive lawn ornament.

Kathi LeSueur

Sent from my iPad

[William Schran]

Had a Geil kiln, but insulating fire brick, while teaching at
community college. Had 4 venturi burners either side coming up from
bottom.
Discussions with others in the past led me to adjust the primary air
on the burners open to the width of a popsicle stick and leave them at
this setting all the time.
When I was taught to fired gas kilns back in the 1970's it was all
flames and black smoke thinking that was good reduction - it was just
wasted gas and black soot! After my time at Haycreek with Mel I
learned fire rather fast, less gas pressure and reduce by adjusting
damper. Also had discussion with folks at Geil Kilns at a NCECA
conference and they also said to cut back gas pressure,
The damper in these kilns (at least mine did) had etched lines on it:
1, 2, 3.... I made additional marks with pencil in between the etched
line at 1/4, 1/2, 3/4. I think I had mine set at 2 1/2 from start to
when I started reduction, pushed in damper to 2 and watched for back
pressure at bottom spy hole that indicated reduction. Did that for an
hour or so, them pulled damper out to 2 1/4 for rest of firing. There
was absolutely no smoke created and looking in spy holes it didn't
seem very cloudy indie the kiln.
I know we got good reduction because I got grant and bought an oxy
probe that showed reading of heavy reduction and got good even
temperature throughout the kiln.
Bottom shelves were laid right on kiln floor and posts for next set of
shelves had the 2nd set of shelves above the exit flue - Geil told me
this was important.
Bill

William Schran...@twc.com703-505-1617

-----------------------------------------From:
"ka...@lesueurclaywork.com"
To: cla...@lists.clayartworld.com
Cc:
Sent: Tuesday July 26 2022 7:36:36AM
Subject: [Clayart] Geil kilns

Kathi LeSueur

Sent from my iPad

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.clayartworld.com/pipermail/clayart/attachments/20220726/a30a9b6b/attachment.htm>

[Donn Buchfinck]

What version of the geil does she have, Size, year produced?
The new geils fire like a dream.

If she has the old cast iron burners on the geil, spin the flaps open to
1", you then leave them alone.
Is she firing with natural gas or propane? Does she have the correct
orifices in the burners for the proper gas type?

Also tell her to not go over 3" gas pressure when firing.

Donn Buchfinck
donn.bu...@gmail.com

-------------- next part --------------
An HTML attachment was scrubbed...

URL: <https://lists.clayartworld.com/pipermail/clayart/attachments/20220726/0187ffee/attachment.htm>

[Robert Santerre]

Hi Kathi. I had a Geil 40 cu ft fiber shuttle kiln, 8 Venturi burners. I did have problems with even firings initially. The problems seemed to be 3-fold - the shuttle door leaked quite a bit at the top, the top shelved pots were not well reduced, the very bottom shelves were also not well reduced. You could see where reduction was poor by looking at the color of the fiber (pink where reduction was poor). I added 2 clamps at the top of the shuttle door to fix that issue. I blocked off (with 2600K bricks) the 2 burners at the back of the kiln to prevent flames from those 2 burners just shuttling heat right into the downdraft vent. The remaining 6 burners were more than enough to fire the kiln nicely. Finally, I made some bag walls (using 2600K bricks) about 12" to 18" high for the remaining 6 burners to drive the flames up to the top of the kiln. I also added an oxy probe (placed just inside the downdraft vent) so I could accurately measure the atmospheric O2 (as an average for the kiln as a whole). When I went into reduction (at around 1600F) I used the damper to adjust the O2 to 0.500. I marked (scribed) the damper and had to make VERY fine adjustments to get a stable 0.500 - 0.550 through-out the firing to 2300F (cone 10). Finally, I would fire down (over appx. 2 hrs) to 1900F (in oxidation) and then close the kiln up. There were still a few cool (non-reduced) spots in the kiln (mostly on the bottom shelf). I knew exactly where they were and used them for any pieces that I wanted to oxidize. Hope this helps your friend. I'll admit it was a bit frustrating initially to get to know this kiln, but once I got it figured out, I fired that kiln with confidence for +300 firings. Made a LOT of good pots - it was NOT a lawn ornament! Bob Santerre, retired Arrowsic Island Pottery.

////////////////////////////////////////////////////////////////////////////////////////////////////////////

[ka...@lesueurclaywork.com]

Thanks, I’ll pass this along.

Sent from my iPad

> On Jul 26, 2022, at 10:00 PM, Steve Dalton <ccpot...@yahoo.com> wrote:
>
> Hi Kathy,
>
> I have the softbrick Geil kiln and mine fires amazingly well. I only have half a cone difference top to bottom.
>
> Did your friend get the kiln’s manual from the retiring potter? There is a lot of information regarding set up and firing.
>
> I bought my Geil through and online auction. A local high school bought it and never used it. I actually had to do the initial setting fire.
>
> I had to change the pilot ring and burner tips from Natural Gas to Propane. In doing that, I had to reset the burner tips into the ports. And, make sure the butterfly valves are set correctly. If I remember correctly, the burner tips go in to the ports 1/2” and the valves are set to 1/8” open. Lastly, I maxed out the pressure regulator to 12 psi at Wide Open.
>
> The best recommendations that I have and did when I got mine. Call or email Geil kilns. Another good source, is Quinn at Clay Art Center in Tacoma, WA. Quinn has the fiber Geil as well.
>
> I hope this helps,
> Steve Dalton
> Clear Creek Pottery
> Lake Stevens, WA
> Sent from my iPhone
>
>> On Jul 26, 2022, at 4:36 AM, ka...@lesueurclaywork.com wrote:
>>
>> A friend bought a Geil kiln from a potter who was retiring. It’s a fiber kiln with six Venturi burners. Three on each side. This kiln has been a nightmare for her. It fires unevenly in both temperature and reduction. She says the only control she has is from the damper. She can’t adjust the air coming in at the Venturi burners.