Jon Brinley on sun 6 feb 05
Hello all,
Well I have spent the last two days cleaning,
sorting, stacking, unstacking, restacking a bunch=20
of bricks. My back is killing me so I'll have another=20
George Dickel and Coke please.
In the meantime I have successfully gotten this=20
project off the ground. In fact, I am ready to put
the roof on it. Then build the chimney.
I will get pictures up somewhere before the week=20
is out. Only the outer shell is up at this time. I will
line it with the insulating firebrick after the roof is on.
Don't want to damage any if I can help it.=20
Had another thought on this if any of y'all could help=20
I would appreciate all input.
Thought: Could it be possible to bond the bricks together
before putting them in the kiln. Kinda like a slab. If so, what
would be the best medium to use to do this?? And where do I=20
get it.
I have seen pieces of a kiln with some type of bonding agent=20
holding the bricks together. If this is possible It would make assembly =
so much easier.
Jon in Midland
=20
Paul Herman on mon 7 feb 05
Hi Jon,
You want to make slabs of brick and then build the kiln out of them?
Hmmm, why not just lay up the interior brick? What's this hullabaloo
about bonding them together first? I imagine it might be possible but
WHY? Bonding them as you build is a way that is proven to work.
Have you made any mechanical connection between the inner and outer
walls? It might be a good idea. Y'know, a brick every now and then tying
the walls together?
And I just have to give you this advice: George Dickle is way too good
to put that nasty "coke" in it, try a little water instead!
Hot kilns,
Paul Herman
Great Basin Pottery
Doyle, California US
http://www.greatbasinpottery.com/
----------
>From: Jon Brinley
>To: CLAYART@LSV.CERAMICS.ORG
>Subject: Midland/Minnesota Flattop
>Date: Sun, Feb 6, 2005, 3:40 PM
>
> Hello all,
> Well I have spent the last two days cleaning,
> sorting, stacking, unstacking, restacking a bunch
> of bricks. My back is killing me so I'll have another
> George Dickel and Coke please.
> In the meantime I have successfully gotten this
> project off the ground. In fact, I am ready to put
> the roof on it. Then build the chimney.
> I will get pictures up somewhere before the week
> is out. Only the outer shell is up at this time. I will
> line it with the insulating firebrick after the roof is on.
> Don't want to damage any if I can help it.
>
> Had another thought on this if any of y'all could help
> I would appreciate all input.
> Thought: Could it be possible to bond the bricks together
> before putting them in the kiln. Kinda like a slab. If so, what
> would be the best medium to use to do this?? And where do I
> get it.
> I have seen pieces of a kiln with some type of bonding agent
> holding the bricks together. If this is possible It would make assembly so
> much easier.
>
> Jon in Midland
Lee Love on tue 8 feb 05
I would not tie the walls together nor bond them. It would
make it difficult to replace the softbrick if you had to. I am not
personally familiar with any other design except the one I have used,
that has softbrick on the inside and hard brick on the outside.
Before you go any farther, I suggest that you look at the photos I made
of the building of my kiln (there are over 60 step by step photos):
http://public.fotki.com/togeika/my_kiln/
If you look at the pictures, you will see that I put the
hardbrick outer walls first and then "filled in" on the inside with
softbrick. I put the softbrick in very snuggly. The soft brick are a
liner and do not bare any of the structural load of the kiln.
If you go here you can see the plans for Euan Craig's
desgin. You can build the walls similarly, just using the flat top
placement for burner, etc.:
http://potters.blogspot.com/2004/02/euan-craigs-kiln-design-these-are-also.html
If you have any questions, I am all ears.
--
in Mashiko, Japan http://mashiko.org
http://potters.blogspot.com/ WEB LOG
http://claycraft.blogspot.com/ Photos!
Vince Pitelka on tue 8 feb 05
> I would not tie the walls together nor bond them. It would
> make it difficult to replace the softbrick if you had to. I am not
> personally familiar with any other design except the one I have used,
> that has softbrick on the inside and hard brick on the outside.
With all due respect to your experience, and certainly to your work, the
above is irresponsible advice. Except in the case of very small kilns, it
is ALWAYS much better to tie inside and outside walls together, because it
gives a stable, secure locked wall that will last almost indefinitely. The
normal pattern is to lay stretcher courses running in line with the wall,
with the inner and outer courses offset by one half brick in order to
minimize allignment of seams, and then every fourth or fifth course lay a
header course, where the bricks lay across the wall, so the ends are exposed
inside and outside. That ties the two layers together. For best results,
the header courses should begin and end with a soap, so that they are offset
2 1/2", and thus the seams do not line up with the stretcher courses above
and below. It is really worthwhile to pay attention to this.
I don't get this idea of leaving the two layers disconnected so that it will
be easy to replace the lining. Seems a pretty pessimistic attitude when
building a kiln. As I see it, if you leave the two layers disconnected,
you WILL have to replace the lining soon, because it will shift around and
destroy itself. Having the two layers interconnected stabilizes the kiln
and makes both layers last longer.
I am not sure I understand this idea of softbrick on the inside and
hardbrick on the outside. I guess if you have a lot of hardbrick laying
around it makes sense, but I can't see any other reason for it. Far better
to just build with softbrick. It costs a little more, but at least the
brick shapes all match, making it easier to build a proper locked wall, with
the inside and outside layers firmly tied together.
- Vince
Vince Pitelka
Appalachian Center for Craft, Tennessee Technological University
Smithville TN 37166, 615/597-6801 x111
vpitelka@dtccom.net, wpitelka@tntech.edu
http://iweb.tntech.edu/wpitelka/
http://www.tntech.edu/craftcenter/
Paul Herman on wed 9 feb 05
Lee,
Think about this statement:
"There is no structural movement of the liner bricks."
Don't you suppose they might move a bit when you heat them up to 1300C?
good hot firings,
Paul Herman
Great Basin Pottery
Doyle, California US
http://www.greatbasinpottery.com/
----------
>From: Lee Love
>To: CLAYART@LSV.CERAMICS.ORG
>Subject: Re: Midland/Minnesota Flattop
>Date: Tue, Feb 8, 2005, 9:47 PM
>
> The
> back wall is set in first and then the side walls are locked in by a
> turned in "U", formed by where the hard hook over at the door. I will
> put some photos up.
Lee Love on wed 9 feb 05
Vince Pitelka wrote:
> As I see it, if you leave the two layers disconnected,
> you WILL have to replace the lining soon, because it will shift around
> and
> destroy itself. Having the two layers interconnected stabilizes the kiln
> and makes both layers last longer.
Vince, It sounds like you have no experience with a
lined kiln? One of the reasons not to overlap hard brick with soft
brick is that the two materials expand at different rates and this
difference tends to wear on the soft bricks. They will actually crack
where they overlap hardbrick. This would actually be weaker.
There is no structural movement of the liner bricks. The
back wall is set in first and then the side walls are locked in by a
turned in "U", formed by where the hard hook over at the door. I will
put some photos up.
--
Lee in Mashiko, Japan http://mashiko.org
http://potters.blogspot.com/ WEB LOG
http://claycraft.blogspot.com/ Photos!
Vince Pitelka on wed 9 feb 05
> Vince, It sounds like you have no experience with a
> lined kiln? One of the reasons not to overlap hard brick with soft
> brick is that the two materials expand at different rates and this
> difference tends to wear on the soft bricks. They will actually crack
> where they overlap hardbrick. This would actually be weaker.
Lee -
I still don't get the idea of a "lined kiln" as a studio kiln. I cannot
imagine any reason to do this. You would not do this in a wood, salt, or
soda kiln, because you need more stability in the inside layer, and thus it
should be tied to the outside layer. And in a reduction gas kiln there
would be no reason to do have a separate lining, because as I said, it would
break down more quickly when not attached than it would if the two layers
were tied together.
I'd love to hear from anyone out there who knows about this idea of "lined
kilns," where the inner and outer layers are disconnected. It goes against
everything I have ever heard about studio kilns. And a difference in
expansion between hardbrick and softbrick is hardly an issue, because very
little heat gets through the inner layer. The outer layer is there
primarily to provide rigidity/stability.
> There is no structural movement of the liner bricks.
Huh? Of course there is structural movement of the liner bricks. There is
always some structural movement over time, but that depends on how well
anchored the bricks are. In a proper locked wall, with the inside and
outside layers tied together, there would in fact be very little structural
movement.
I'll be interested in seeing the photos, but I still haven't heard any
compelling explanation of why the "lined kiln" makes any sense at all. I'm
always open to a new idea (or an old idea that's new to me), but this one
still doesn't make any sense to me.
- Vince
Vince Pitelka
Appalachian Center for Craft, Tennessee Technological University
Smithville TN 37166, 615/597-6801 x111
vpitelka@dtccom.net, wpitelka@tntech.edu
http://iweb.tntech.edu/wpitelka/
http://www.tntech.edu/craftcenter/
Lee Love on thu 10 feb 05
Vince Pitelka wrote:
> I still don't get the idea of a "lined kiln" as a studio kiln.
I understand. There are many ideas I don't get either. ;-) I
normally don't understand flattop kilns, but I see Jon is trying to
do it with what he has.
But Jon wasn't asking for "opinions" about what he is doing
with his salvaged materials. He just wanted to know how to put a
softbrick liner inside his red hardbrick kiln. I think this is great,
trying to make something with what you got. It relates to something
I want to do: build an Oya stone kiln lined with soft brick (they use
Oya stone for walls and the foundations of traditional buildings around
here. It is a volcanic sandstone.) Wouldn't need a metal frame with
an exterior like this and the kiln would cool very slowly.
I shared photos with Jon showing how I lined my kiln. Euan
just finished 100 firings with a kiln of this design.
Can't wait to see what Jon comes up with.
--
Lee in Mashiko, Japan http://mashiko.org
http://potters.blogspot.com/ WEB LOG
http://claycraft.blogspot.com/ Photos!
dannon rhudy on thu 10 feb 05
Vince said:
>
> I'd love to hear from anyone out there who knows about this idea of "lined
> kilns," where the inner and outer layers are disconnected. .......
Vince, the only observation I've had of "lined" kilns
is with large commercial "train" kilns, where the
wares move through the kiln on a car, starting cold and
ending cool enough to unload the car. These, of course,
are utterly different from studio kilns. They are deliberately
made so that they can be relined every few years.
As you said, keeping the inner and outer layers of a
brick studio kiln disconnected is counterproductive in
my experience (which is not nearly so vast as your own,
I might add). If the two walls are meant to work together,
they ought to be tied together with header courses. Doesn't matter if the
inner is soft and the outer hard.
regards
Dannon Rhudy
Lee Love on fri 11 feb 05
Paul Herman wrote:
>Lee,
>
>Think about this statement:
>
>"There is no structural movement of the liner bricks."
>
>Don't you suppose they might move a bit when you heat them up to 1300C?
>
>
Yes they move. That is why you wouldn't want to interlock them
with the hard brick. They would wear against each other.
Besides, that would defeat the purpose of using the softbrick as a
liner. You would have a fireface liner of both types of bricks.
By "structural" I mean that the hard brick bares all the
weight. You can take the soft brick liner out and the arch will still
stay up. Heck, you could firer it with the soft brick taken out if
you wanted to.
Several folks have made the same design out of all hard
brick. Takes twice as long to fire. Most of these kilns that I am
aware of are outside and the hard brick weathers better. This
combination insulates well enough but doesn't cool quickly. Euan
built his first one out of used low fire soft brick. The firebox of
course, is all hard brick. He has fired it a 100 times (about once a
month for almost 10 years.) With the low duty bricks, he sands
the surface down after 50 firings. He never coated the soft brick.
I think when he moved it to his new place, he had to buy new bricks for
the arch.
Here, high duty insulating brick cost almost $5.00 a piece
. I got most of my hard brick for 80 cents a piece.
--
Lee in Mashiko, Japan http://mashiko.org
http://potters.blogspot.com/ WEB LOG
http://claycraft.blogspot.com/ Photos!
Lee Love on fri 11 feb 05
dannon rhudy wrote:
>I might add). If the two walls are meant to work together,
>they ought to be tied together with header courses. Doesn't matter if the
>inner is soft and the outer hard.
>
>
>
Yeah, "If the two walls are meant to work together." But that
isn't the case in this design..
. It doesn't matter only if you are not trying to make a
complete, unbroken liner. DOH! ;^)
If you interlock them, then you have some hardbrick on
the fireface and some insulating brick on the outside. It defeats the
purpose of a liner.
I am guessing you have never tried this either, because
you would find that the bricks are slightly different sizes (I think
Vince mentioned this as a reason to use all insulating brick in his
first post on the subject.) . Also, on the first firing, the two
kinds of brick shrink at a slightly different rate. If the bricks are
used/old, as in Jon's case, the shrinkage has probably already
happened. You could use mortar to make things fit, but that would
make it harder to take the kiln apart and rebuild or move it.. I
didn't use mortar on the insulation bricks in the liner or arch.
Like you mentioned, the old commercial tunnel kilns are
made this way, with an insulation brick liner. All the commercial
gas and oil kilns here in Japan (the ones that most potters use) are
similar, in that they have a structural steel shell that is lined with
softbrick. I am guessing this might have been what gave Euan the
idea. That, along with starting out with salvaged materials like Jon
is doing.
--
Lee in Mashiko, Japan http://mashiko.org
http://potters.blogspot.com/ WEB LOG
http://claycraft.blogspot.com/ Photos!
Jon Brinley on sun 13 feb 05
Hello All,
Didn't get the chance to post pictures this week, sorry.
I will get them up soon. I have taken a lot of pictures.
The post about silica in kiln wash hit close to home.=20
I am using creek sand for the floor of my kiln. We have=20
a large sand bar in the creek, that upon closer inspection
is quartz sand. I think this will save me even more in=20
the long run, money wise that is. Not having to buy=20
hard brick for the floor.
The usage of sand on kiln floors has been around along=20
time. Potters in the south especially have used this.
The best part is if you have to replace it, its still free.=20
Chimney will need modifying after a firing or two. Not sure how=20
tall it needs to be. Now its only six feet top to bottom.
I am at the stage now I need to set the burners. I need to devise
some contraption to hold them up.
I will call the gas company tomorrow to discuss the issue of=20
setting a tank.
If the salt mine doesn't get me, I will be finished by weeks end.
Jon in Midland
I really don't work in a salt mine, it's just what I call it
Paul Herman on mon 14 feb 05
Hi Jon in Midland,
This below caught my eye.
> I am using creek sand for the floor of my kiln.
I'm wondering if the close inspection of the creek sand included firing
some to the anticipated working temperature. It's highly recommended (by
me) that you test fire it.
I recall the first woodkiln I ever got to fire in, in Port Angeles,
Washington. They originally had an earthen floor, no brick. The first
couple of firings everything was dandy. Then one time they got it good
and hot and it turned into an impessive "lava flow". Al, the kiln
owner, had a big slab of it leaning on the outside of the kiln, and it
was just like brownish red, bubbly basalt, except there were posts and
some shards sticking out of it. It looked like the Lava Beds up atx Tule
Lake. Quite a mess, they rebuilt the floor out of brick.
So I implore you, please test the sand before firing a load of ware on
top of it.
Looking forward to the pics,
Paul Herman
Great Basin Pottery
Doyle, California US
http://www.greatbasinpottery.com/
----------
>From: Jon Brinley
> I am using creek sand for the floor of my kiln. We have
> a large sand bar in the creek, that upon closer inspection
> is quartz sand. I think this will save me even more in
> the long run, money wise that is. Not having to buy
> hard brick for the floor.
> Jon in Midland
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