[Mark C.]

One thing I have noticed is a most folks load kilns with pre-conceivedconcepts.

What I have learned over many years at this is that as long as you leaveroom for kiln to draw and draft properly you can stuff it with great results-

Now I’m a functional studio potter in the business to makefire and sell as much as I can so efficiency is a must-this is not a schoolsituation

I put pots under lower shelves some as well as on forwardbricks-I long ago switched to advancer shelves –which for me paid forthemselves in less than two years with the extra two feet of stacking spacesaved per load-two feet-35 loads per year big kiln really adds up

I put as many pots as I can fit in each load . The kilnalways works fine and all pots get loaded where they need to go either in thecool zone near the flue or the hottest area dead center-I glaze enough of all glazesto fill each area. Folks say I stuff a kiln and I do with great results-so nexttime try stuffing that gas kiln-just leave the areas that need to drawempty-but the load area needs to be stuffed no matter what you heard from others or learned in school-tryit-it works
Now one kiln this is not good to do is the salt kiln-as the salt fumes need to get around-I have attached a salt load photo

Mark

[TypicalGirl]

GREAT info!
I have fired my new downdraft 3 times with mixed results, and I expect its in part because I am not loading it fully enough. Saving for more shelves to remedy that. Your pics are really helpful!

[neilestrick]

Nice loads! I agree completely. The fuller the better. Gas kilns love a full load, long as the draft isn't blocked. I always loaded on the bag wall and in front of the bottom shelf, too. Great pots come from those areas. Do you have a flue channel under your bottom shelf?

[Mark C.]

neilestrick, on 12 January 2012 - 08:07 PM, said:

Nice loads! I agree completely. The fuller the better. Gas kilns love a full load, long as the draft isn't blocked. I always loaded on the bag wall and in front of the bottom shelf, too. Great pots come from those areas. Do you have a flue channel under your bottom shelf?

Yes There is flue channel under shelves-This is my 3rd car kiln I have made


I also have a small gas updraft which has its own issues as its an updraft-nuff said on it-I fire it about 12-15 loads a year
usually special temp/glaze loads-say coleman glazes cone 9 or Otto/Vivica glazes also less than cone 10 and less reduction.

I started with silicon carbide shelves in the 70's went to 1 inch english dry hi alumina then to advancers about 10-12 years ago
Have about 55-60 of them for loading all kilns at same time which happens here more than I like.

[Red Rocks]

Mark

Have you ever tested the Chinese knock-offs of the Advancer shelves? I have talked to several people who have and as usual they had mixed results.

Thanks

[neilestrick]

Red Rocks, on 01 August 2012 - 10:25 AM, said:

Mark

Have you ever tested the Chinese knock-offs of the Advancer shelves? I have talked to several people who have and as usual they had mixed results.

Thanks

In general those shelves work great. I ran several 14x28's in my gas kiln, and now use them in my electric. A friend has been using a couple in his anagama with good results. There were some cases of these shelves cracking a few years ago when they first came onto the market, and Bailey is recommending that they not be used in electric kilns. Axner on the other hand, is selling round shelves specifically for electrics. No one seems to be having any issues in gas kilns.

[JBaymore]

The real Advancers just need to be kept dry.....as most woodfirers have found out the hard way.

best,

......................john

[Red Rocks]

Thanks John and Neil for the response on the Advancers - can you recommend a specific brand and supplier(s)? I would prefere western states as I am in AZ.

[Mark C.]

I would deal with Smith -sharp at Fire Brick supply-I bought over 40 of my advancers there-I think they are the main supplier for these shelves in the USA
They used to have some price breaks at different levels.
Ask for Donna she knows her stuff on these.

http://www.ssfbs.com/
Mark

[Red Rocks]

I just visited a studio of another potter here in Sedona and he has been using the Advancer knock-offs from China for about 3 years in a cone 10 reduction gas kiln and has had no problems... nice to hear and see.

[yedrow]

My experience with the Chinese knockoffs is pretty bad. That being said, there may be several kinds, I don't know. I do know that Advancers are excellent and worth the money. We got some Chinese shelves about five years ago. The internal stresses in the shelves were so bad that they had to cut two gaps in both sides and one in each end to relieve them. And, during the time firing they warped severely. Also, two of them broke under low stress during the first month we had them. For the first three years we fired to ^10+ once a week for 8 months and five times a month for the rest of the year in a 90 cu.ft. Geil kiln. In three years the Chinese shelves were like pringle chips. During that time our Advancers were clean and strait. We've had the same Advancers (less modest breakage) for about nine years, under a heavy production load.

[Marcia Selsor]

Mark,
I like the advancers too but what shelves are you using in the Salt kiln? The don't look like silicon carbide and definitely not advancers.

Just curious. I have some odd shapes of silicon carbide shelves I have been hauling around for years hoping to set up a soda kiln somewhere. Ah, I reread the high alumina info.

I think stacking kilns tightly in most cases gives the best results, most control, and is efficient.
Great example. Thanks for posting the photos.

Marcia

[Red Rocks]

Yedrow

That is unfortunate to hear - must mean there are different manufacturers because the potter I visited is a serious potter, firing on average twice a week for over 3 years. He bought his directly from China, through a group that went there to buy them. Sure means I need to dig deeper before buying any.

Thanks for the response.

[yedrow]

Red Rocks, on 07 August 2012 - 07:26 PM, said:

Yedrow

That is unfortunate to hear - must mean there are different manufacturers because the potter I visited is a serious potter, firing on average twice a week for over 3 years. He bought his directly from China, through a group that went there to buy them. Sure means I need to dig deeper before buying any.

Thanks for the response.

I don't mean to bang on the nitride bonded shelves but when you lean over to adjust a pot on the far side of the kiln and a brand new nitride bonded shelf breaks under the partial pressure of your body it makes an impression, lol. I'll see if we have any fragments lying around and get a pic. We got ours through Geil and Paul really was pushing them. These days though I'm guessing a lot of the kinks have been worked out. As I was told, the NB shelves are press molded while the Advancers are slip cast. I do know that it can be a real bear getting an order of advancers. My experience is from years ago. There is probably more current info out there that would be better.

[Mark C.]

I wish we had a ceramic retailer on this forum to explain things sometimes.
I will take a stab at shelves.
Most of my experience is at cone 10-11
The ones used mostly in electrics are mullite based which has great strength at low temps
these also come in just about all sizes and thicknesses and will warp at cone 10 over time even in 1 inch thickeness
Mullite is just one of the shelves ingredients these are made from and are very much like cordilite shelves
which now come with a hollow core version that work well at cone 10 and have a hollow honey comb structure.
The original high fire shelves I knew back in the day are silicon carbide and came in various sizes and thicknesses the thicker the better for less warpage at high temp.
Then came along dry pressed high alumina English shelves-these also came in various thicknesses and sizes and warp less than silicone carbide did.
They are heavier and a 12x24 1 inch weighs 33#I know this factoid as i own 45 of them and used to load them every week.
Then came the nitride bonded miracle shelves-the best one are made by saint goblain ( http://www.ceramicma...gobain.com/)and are known as Advancers-their are
a few lesser like bonded shelves.
Then came the china knock offs which are not as good as the rest. ( I have tested 3 of them and can say that)

Marcia
My salt shelves are the dry pressed English high alumina as I have a lot of them not used anymore in reduction.
Mark

[neilestrick]

The thin Chinese shelves and Advancers are not a direct comparison. The Chinese shelves are thin, but not quite as thin as Advancers. That is where the similarities end. They are as strong as any other silicon carbide shelf, but not as strong as Advancers. However they are 1/3 the price of Advancers, and generally cheaper than the standard 3/4 inch thick SilCar shelves. Shelves imported by one company might be made in several different factories in China, all with different levels of quality. So if you happen to get a good batch, and I think they have gotten much better over the last couple of years from what I have heard, then the Chinese shelves are a great value.

I have heard nothing but good reports about the CoreLite (honeycomb) shelves. Lill Street in Chicago has been using them in their gas kilns and have had no warping problems at all. I'm going to invest in a few 14x28's for my big electric some time this year. The down side of them is that they are very thick. The price is good, though.