Larry Kruzan on mon 26 oct 09
her ramblings
5 years - no kiln wash. Rotate each firing. I keep track of which side was
up with a very simple method - After I open the kiln and before I move one
pot, I use a sharpie to make a big X on the top of every shelf. When I
restack I look for the X, and put it down.
One time I was playing with some clay tests and had some minor plucking wit=
h
a clay that was over-fluxed for the temp I was using - not much and the cla=
y
was never used except for this one test.
Larry Kruzan
Lost Creek Pottery
www.lostcreekpottery.com
-----Original Message-----
From: Clayart [mailto:Clayart@LSV.CERAMICS.ORG] On Behalf Of jonathan byler
Sent: Monday, October 26, 2009 5:06 PM
To: Clayart@LSV.CERAMICS.ORG
Subject: larkin nitride bonded silicon carbide shelves + kiln wash + other
ramblings
We just got in a load of 18x18 nitride bonded silicon carbide shelves
from larkin. We are going to be using them for regular old ^10
reduction firings. I did an initial firing today to burn out whatever
stuff may off gas as was recommended, and I was going to try putting a
dot or three of glaze on the edge of one of the shelves to see how
much it eats into the shelf, but I completely forgot.
I was wondering if people have been using kiln wash on these, or just
leaving them bare... we usually use a rough mix of two scoops alumina
hydrate to 1 scoop of epk and 1 scoop of silica... not exactly
scientific, but it has worked well on our high alumina shelves over
the years. I am concerned about using kiln wash because there are
slits cut into the shelves for stress relief, and I am thinking that
kiln wash will get into the slits and possibly fall on the ware below.
any thoughts?
thanks,
jon
p.s. the shelves seem o.k. at first glance, one or two were slightly
thicker than others, and a few were warped maybe 1/16 - 1/8 inch
across 18" of width. but for about $66 each delivered, I can live
with that... for the advancers people wanted 4-5 times that plus
delivery (bailey wants like 10-20% of the advertised shelf cost just
to pack them) and then I would have to baby them a lot more. Babying
them is not such an option in a university environment. Hopefully
these work out well.
William & Susan Schran User on mon 26 oct 09
her ramblings
On 10/26/09 6:06 PM, "jonathan byler" wrote:
> I was wondering if people have been using kiln wash on these, or just
> leaving them bare... we usually use a rough mix of two scoops alumina
> hydrate to 1 scoop of epk and 1 scoop of silica... not exactly
> scientific, but it has worked well on our high alumina shelves over
> the years. I am concerned about using kiln wash because there are
> slits cut into the shelves for stress relief, and I am thinking that
> kiln wash will get into the slits and possibly fall on the ware below.
All the testing I have done of the nitride bonded shelves has been without
kiln wash. Have had several glaze accidents on them, but all came off using
angle grinder.
If you do decide to go with kiln wash, use the alumina and epk, don't add
the silica.
> p.s. the shelves seem o.k. at first glance, one or two were slightly
> thicker than others, and a few were warped maybe 1/16 - 1/8 inch
> across 18" of width. but for about $66 each delivered, I can live
> with that... for the advancers people wanted 4-5 times that plus
> delivery (bailey wants like 10-20% of the advertised shelf cost just
> to pack them) and then I would have to baby them a lot more. Babying
> them is not such an option in a university environment. Hopefully
> these work out well.
We have twenty 12x24" Advancer shelves at my community college ceramics
program. Maybe since I told the students each shelf is $160 they have
treated them with some respect.
Bill
--
William "Bill" Schran
wschran@cox.net
wschran@nvcc.edu
http://www.creativecreekartisans.com
jonathan byler on mon 26 oct 09
her ramblings
Hi Bill,
you must be better at putting on the stern face than we are...
unfortunately cost doesn't seem to matter to some folks, especially
when it isn't "their" money.
despite being extra cautious about what I put in the kiln, someone (or
three or four someones) always manages to get in something triple
dipped and extra runny without me noticing. When you are grinding the
glaze runs off the shelves, do they tend to stay superficial and on
the surface? or do they ever eat their way into the shelf like
happens a lot with the high alumina shelves (especially with iron-rich
glazes)?
also why would you leave the silica out of the kiln wash when applying
to the nitride bonded shelves?
thanks,
jon
On Oct 26, 2009, at 7:04 PM, William & Susan Schran User wrote:
> On 10/26/09 6:06 PM, "jonathan byler" wrote:
>
>> I was wondering if people have been using kiln wash on these, or just
>> leaving them bare... we usually use a rough mix of two scoops alumina
>> hydrate to 1 scoop of epk and 1 scoop of silica... not exactly
>> scientific, but it has worked well on our high alumina shelves over
>> the years. I am concerned about using kiln wash because there are
>> slits cut into the shelves for stress relief, and I am thinking that
>> kiln wash will get into the slits and possibly fall on the ware
>> below.
> All the testing I have done of the nitride bonded shelves has been
> without
> kiln wash. Have had several glaze accidents on them, but all came
> off using
> angle grinder.
> If you do decide to go with kiln wash, use the alumina and epk,
> don't add
> the silica.
>
>> p.s. the shelves seem o.k. at first glance, one or two were
>> slightly
>> thicker than others, and a few were warped maybe 1/16 - 1/8 inch
>> across 18" of width. but for about $66 each delivered, I can live
>> with that... for the advancers people wanted 4-5 times that plus
>> delivery (bailey wants like 10-20% of the advertised shelf cost just
>> to pack them) and then I would have to baby them a lot more. Babying
>> them is not such an option in a university environment. Hopefully
>> these work out well.
> We have twenty 12x24" Advancer shelves at my community college
> ceramics
> program. Maybe since I told the students each shelf is $160 they have
> treated them with some respect.
>
> Bill
>
> --
> William "Bill" Schran
> wschran@cox.net
> wschran@nvcc.edu
> http://www.creativecreekartisans.com
>
>
>
William & Susan Schran User on mon 26 oct 09
her ramblings
On 10/26/09 8:18 PM, "jonathan byler" wrote:
> despite being extra cautious about what I put in the kiln, someone (or
> three or four someones) always manages to get in something triple
> dipped and extra runny without me noticing. When you are grinding the
> glaze runs off the shelves, do they tend to stay superficial and on
> the surface? or do they ever eat their way into the shelf like
> happens a lot with the high alumina shelves (especially with iron-rich
> glazes)?
>
> also why would you leave the silica out of the kiln wash when applying
> to the nitride bonded shelves?
The glaze appears to remain on the surface.
These shelves do have a much higher absorption rate than Advancer shelves,
and a bit of glaze seems to "stain" the surface, but the surface after
grinding does not cause other pots to stick in that area.
I have cleaned one shelf multiple times.
The shelves without wash seem to want to "pluck" porcelain and adding silic=
a
can cause issues with porcelain clays. It's also more dangerous when
grinding wash containing silica.
Bill
jonathan byler on tue 27 oct 09
her ramblings
paul
we are only three hours from them, shipping was a little over $100.
we also got a price break for buying more than 20 I think? 20 or more
and they knocked at least $5 off the price. unit price was $65 each.
we are going to try them out for a while and see. if they don't work
out, I will try the corelites, but I really want something that
doesn't get screwed up from glaze runs.
> Jon,
> that price sounds very strange to me - $66 delivered for 18X18 nitride
> bonded. The last time i called larkin they quoted me $78 PLUS
> shipping for
> 18X24 oxide bonded which are cheaper. Even though they are slightly
> bigger
> it sounds like the ones you got were disproportionately cheaper. How
> did you
> get that deal?
>
> paul
> ---------- Forwarded message ----------
> From: jonathan byler
> Date: Mon, Oct 26, 2009 at 6:06 PM
> Subject: larkin nitride bonded silicon carbide shelves + kiln wash +
> other
> ramblings
> To: Clayart@lsv.ceramics.org
>
>
> We just got in a load of 18x18 nitride bonded silicon carbide shelves
> from larkin. We are going to be using them for regular old ^10
> reduction firings. I did an initial firing today to burn out whatever
> stuff may off gas as was recommended, and I was going to try putting a
> dot or three of glaze on the edge of one of the shelves to see how
> much it eats into the shelf, but I completely forgot.
>
> I was wondering if people have been using kiln wash on these, or just
> leaving them bare... we usually use a rough mix of two scoops alumina
> hydrate to 1 scoop of epk and 1 scoop of silica... not exactly
> scientific, but it has worked well on our high alumina shelves over
> the years. I am concerned about using kiln wash because there are
> slits cut into the shelves for stress relief, and I am thinking that
> kiln wash will get into the slits and possibly fall on the ware below.
>
> any thoughts?
>
>
> thanks,
> jon
>
>
> p.s. the shelves seem o.k. at first glance, one or two were slightly
> thicker than others, and a few were warped maybe 1/16 - 1/8 inch
> across 18" of width. but for about $66 each delivered, I can live
> with that... for the advancers people wanted 4-5 times that plus
> delivery (bailey wants like 10-20% of the advertised shelf cost just
> to pack them) and then I would have to baby them a lot more. Babying
> them is not such an option in a university environment. Hopefully
> these work out well.
Ingeborg Foco on tue 27 oct 09
her ramblings
> Bill,
>
I agree that glaze drips stain the shelves. I work with a lot of runny and
fussy glazes and I use a putty knife to scrape the drips off. I'm careful=
l
and wear safety goggles since there are often very sharp pieces that fly
off. After scraping, I flip the shelves. The next firing those stains
somehow fire off (don't know how to explain it well) leaving a very light
bubbly film almost like fluff that is easily removed with the putty knife
and the shelf is clean for the next flip.
Personally, I don't care about the stained appearance. I do really like
not using wash and as I said, using fussy glazes makes it much easier with
these shelves. On the down side, they are warped and were when I got them
new. I have had several of them crack and I have to examine them after eac=
h
firing to look for cracks and potential problems. Not a good thing.
I mark the shelves with RIO on one side and that tells me which side to use
for this particular firing. Kiln log says "mark down" or "mark up."
I still want Advancers and one of these days I shall get them.
Ingeborg
> The glaze appears to remain on the surface.
> These shelves do have a much higher absorption rate than Advancer shelves=
,
> and a bit of glaze seems to "stain" the surface, but the surface after
> grinding does not cause other pots to stick in that area.
> I have cleaned one shelf multiple times.
>
> The shelves without wash seem to want to "pluck" porcelain and adding
> silica
> can cause issues with porcelain clays. It's also more dangerous when
> grinding wash containing silica.
>
> Bill
>
--
Sincerely,
Ingeborg
http://www.thepottersworkshop.com
William & Susan Schran User on tue 27 oct 09
her ramblings
On 10/27/09 5:05 PM, "Ingeborg Foco" wrote:
> I still want Advancers and one of these days I shall get them.
Well, start buying one at a time...
Think of it like investing, just investing in yourself.
Bill
--
William "Bill" Schran
wschran@cox.net
wschran@nvcc.edu
http://www.creativecreekartisans.com
William & Susan Schran User on wed 28 oct 09
her ramblings
On 10/27/09 10:17 PM, "jonathan byler" wrote:
> we are only three hours from them, shipping was a little over $100.
> we also got a price break for buying more than 20 I think? 20 or more
> and they knocked at least $5 off the price. unit price was $65 each.
> we are going to try them out for a while and see. if they don't work
> out, I will try the corelites, but I really want something that
> doesn't get screwed up from glaze runs.
If the glaze runs issue is your main concern, stick with the nitride bonded
shelves. The Corelites will be like any other cordierite/high-alumina shelf=
,
needing kiln wash and removal of any glaze that gets into the shelf by
grinding.
Bill
--
William "Bill" Schran
wschran@cox.net
wschran@nvcc.edu
http://www.creativecreekartisans.com
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