[Clayart] lining a salt or soda kiln

[Village Lady]

I have a half-soft/half-hard brick gas kiln lined with 1/2” of ceramic fiber.  What do you think about using it for salt or soda firing?

Karen

Karen Shuler
Villagelady10 at gmail.com

> On Jun 12, 2023, at 2:36 PM, vincepitelka at gmail.com wrote:.  
> 
> A salt or soda kiln will last longer if made out of hardbrick, but you do not have to make them out of hardbrick if you're not going to be doing production.  At this point, I am sorry I didn't build mine out of softbrick, because I only fire four to six times a year, and a soft brick hotface with a good resistant spray-on liner would last decades and my fuel consumption would be a lot lower.  Years ago Wil Shynkaruk and also Ruggles and Rankin recommended a spray-on zirconia (zirconium oxide) (do not use Zircopax, which is zircon - zirconium silicate) coating for softbrick wood, salt, and soda kilns.  You can buy zirconium oxide on eBay  - ten pounds for about $100, which should be enough to spray a good-sized kiln when combined with 5% ball clay as a binder.  
> 
> My friend Joe Winter (was partners in the big anagama at Great Basin Pottery with the late Paul Herman) built a propane-fired softbrick salt kiln seven or eight years ago, and it has held up pretty well with frequent firings.  He sprayed on a liner, and I don't remember what he used, but I could find out. 
> 
> You don't want to saturate the brick all the way through, because that would greatly diminish the insulating properties.  Nor do you want to build up the coating heavily on the surface, because that would likely peel off from differential expansion/contraction.  I wish someone would do some solid research on this.  It's not anything I want to undertake.  My firing costs are high, but I don't fire very often, and the first few pots out of the kiln pay the fuel costs, so I can't complain.  
> - Vince   
> 
> Vince Pitelka
> Potter, Writer, Teacher
> Chapel Hill, NC
> vpitelka at dtccom.net
> www.vincepitelka.com 
> https://chathamartistsguild.org/ 
>