search  current discussion  categories  kilns & firing - wood 

wood fire -- olsen kiln

updated tue 17 mar 98

 

Mary Dye on fri 20 feb 98


> ----------------------------Original message----------------------------
> > I want to rebuild my wood-burning kiln with a fast fire wood kiln. Does
anyone
> have any comments about the general plans presented in the Olsen Kiln
Book? I
> would like the kiln to be slightly bigger than the one in the book. Maybe
50-60
> cubic feet. How much wood does a firing take? Does the kiln fire evenly?
etc.
> Thanks for any help.
> Alan
__________________

Alan--
I built a modified Olsen Fast-fire last fall. I found the plans and the
pictures in the book to be good guides, but I also drew up very detailed
plans and had a brick count before I started. My kiln is a bit deeper
(front to back) than the original -- the interior wall that divides the
fireboxes is 2 and 1/2 bricks thick, instead of 1 as in the plans. I also
made it a bit taller -- by two brick courses. One extra course to make the
fireboxes taller, and one extra course above. I didn't make it wider, but
a modest adjustment in this direction (one brick length?) seems reasonable.
The chimney is 11 and 1/2 ft. tall, which is a bit short, but the kiln is
firing fine -- the main flue into the chimney is also taller by 1 brick .
The walls are double-thick (his walls are one brick thick in the book) and
the arch is also 9 inches thick. If I was going to build it again and make
it larger, I'd do it by making it deeper still -- making the interior
firebox wall thicker (hollow, maybe...). I wouldn't make the fireboxes
themselves wider if I was going to stick to using shelves to span their
tops and form the floor of the kiln.

To answer your specific questions --
How much wood? -- about 1/3 cord of wood to cone 10/11 in 8-9 hours. I'm
using "urban scrap" -- pallet pieces, pine 2x4s, leftovers from remodeling
projects, stuff that people throw away when they clean their basements, and
dumpster/trash pile pickings (no painted or treated stuff). One trip to
the rear of Wal-Mart w/ my van and a couple of passes up and down
residential alleys usually nets plenty for one firing.

Fire evenly? -- I've had differences of 1/2 to 1 cone from top to bottom
w/ the top being hotter.

Good luck! I think its a great kiln, and I love the way it fires!

-- Mary in ChicagoLand

The Slack-DeBrock Family on mon 16 mar 98

Hi Alan...I have a fastfire kiln that Fred Olsen helped us build during a
workshop a couple of years ago. Based upon what is in the book and what i
learned through his supervision, there are some details that were hard to
realize had i only had the book to go by. I do have a set of slides that
show the actual building of the kiln and point out some essential detail. I
also offer workshops for people who are thinking of building such a
kiln---we cover glazing and fire effects, do an actual firing to cone 10,
and cover the construction aspects. The workshops run 3 days, and there
will be one in April and one in September. If you'd like more information
I'll send you a flyer.

The kiln we built is about 40 cubic feet, and it fires very nicely. I do
have a cold spot in the back corner, and about 1-2 cone difference between
top and bottom, but each time it's a challenge to even it out, and it is
amazing how responsive the kiln is to every little change. We use about 1/3
cord of wood for a 8-9 hour firing that goes to Cone 11 top, 10 bottom, so
it is very efficient nd conservative on fuel. Let me know if you have any
questions--I'd be glad to offer whatever help I can.

Joan Slack-DeBrock/River Run Pottery
P.O.Box 95
McNaughton, WI 54543
715-277-2773
riverrun@newnorth.net