#1  
Old 11-28-2007, 12:59 AM
Serf
 
Join Date: Nov 2007
Location: Australia
Posts: 1
Question Should I mix anything with my clay wall layer?

I am building a clay oven in my backyard and would appreciate some help. I have built the foundation and sand form and am ready to put the clay layer over the form which will be 6" thick with a cow dung/clay/sand stucco over the outside which will be 1" thick. I have bought Buff Raku clay from a pottery supply which has a high grog (ground fire brick) content. I am not sure weather to mix any sand with this and if so in what ratio. I have heard varying reports as to weather this is necessary or not because of my high grog content clay and that the sand will keep falling into the food as the oven ages. I intend to wet the clay down to a more pliable consistency before use and would prefer not to add sand as this is more work. Will pure groggy clay crack easier than the same clay mixed with sand?
Please help,
Mattyana
Reply With Quote
  #2  
Old 11-28-2007, 07:33 AM
Archena's Avatar
Il Pizzaiolo
 
Join Date: Apr 2007
Location: Alabama
Posts: 1,212
Default Re: Should I mix anything with my clay wall layer?

I'm not sure - I've always thought sand was the filler and that straw was the binding agent when used. I don't see why sand should increase binding.
__________________
"He is no fool who gives what he cannot keep to gain what he cannot lose." - Jim Elliot

"Success isn't permanent and failure isn't fatal." -Mike Ditka
[/CENTER]
Reply With Quote
  #3  
Old 11-28-2007, 03:45 PM
dmun's Avatar
Moderator
 
Join Date: Jul 2005
Location: New Jersey USA
Posts: 4,216
Default Re: Should I mix anything with my clay wall layer?

Grog, at least when I was a potter, was fired clay, ground in a ball mill then sifted to the proper size granule. I don't think it has any specific alumina content like refractory products, unless it's something special. It's intended to add strength to the fired clay body, not provide any temperature resistance.

Manure? In an oven? I know this is traditional, but I hope you are going to cure this with long, hot fires before you put any food in the oven. Won't it, you know, smell?
Reply With Quote
  #4  
Old 11-28-2007, 08:50 PM
Archena's Avatar
Il Pizzaiolo
 
Join Date: Apr 2007
Location: Alabama
Posts: 1,212
Default Re: Should I mix anything with my clay wall layer?

No, manure only smells when fresh - it's urine that won't lose its smell. Dried manure has little or no odor and doesn't regain it when rehydrated.

Don't ask how I know that...
__________________
"He is no fool who gives what he cannot keep to gain what he cannot lose." - Jim Elliot

"Success isn't permanent and failure isn't fatal." -Mike Ditka
[/CENTER]
Reply With Quote
  #5  
Old 11-28-2007, 09:03 PM
Il Pizzaiolo
 
Join Date: Jan 2007
Location: Tampa, FL
Posts: 1,446
Default Re: Should I mix anything with my clay wall layer?

Its amazing what you retain from watching the Discovery Channel
We certainly don't think it is from firsthand experience
Reply With Quote
  #6  
Old 11-28-2007, 09:44 PM
Master Builder
 
Join Date: Oct 2007
Location: Sacramento, CA
Posts: 575
Default Re: Should I mix anything with my clay wall layer?

I don't even WANT to know!

dusty
Reply With Quote
  #7  
Old 11-29-2007, 05:52 AM
asudavew's Avatar
Il Pizzaiolo
 
Join Date: Jul 2007
Location: san angelo, texas
Posts: 1,877
Default Re: Should I mix anything with my clay wall layer?

Quote:
Originally Posted by Archena View Post
No, manure only smells when fresh - it's urine that won't lose its smell. Dried manure has little or no odor and doesn't regain it when rehydrated.

Don't ask how I know that...

So how do you know?

Someone had to ask..
__________________
My thread:

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

My costs:

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

My pics:

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Reply With Quote
  #8  
Old 11-29-2007, 06:11 AM
Serf
 
Join Date: Oct 2007
Location: Bozeman MT
Posts: 18
Default Re: Should I mix anything with my clay wall layer?

A little info

Handy Home Projects: final plaster layer for the mud oven - clay manure mix

Rich

Last edited by rcspott; 11-29-2007 at 06:14 AM.
Reply With Quote
  #9  
Old 11-29-2007, 07:50 AM
Serf
 
Join Date: Sep 2007
Location: Central Valley, CA
Posts: 21
Cool Re: Should I mix anything with my clay wall layer?

asudavew,

My wife knows. Born in Mexico; her family was poor, and everyone worked on the ranch. When she was little, they would burn dried cow pies as fuel for their oven. Each family that worked on the ranch had their specific section where they could gather the dried cow pies. No odor!

Guertio
Reply With Quote
  #10  
Old 11-29-2007, 12:44 PM
Apprentice
 
Join Date: Apr 2007
Location: UK
Posts: 100
Default Re: Should I mix anything with my clay wall layer?

I'm going to use a recipe from John Conrad's book "Contemporary Ceramic Formulas" to make my oven walls. The book contains a whole chapter on refractories, and has a range of recipes to make refractory materials, including firebricks and crucibles.

The recipe I'm using will be 70% firebrick grog, 25% fireclay, 5% ballclay. The firebrick grog is just ground up firebricks, so this stuff is as close as I can get to 'mould your own firebrick'. The alumina content of the grog is high, so it should hold heat just like firebrick. I'll report back here once I've done it - I'm working on a roof for my oven right now so all the clay doesn't wash away in the rain...

As I understand it from Kiko's book, the thermal expansion rates of sand and clay differ, so they can lead to sand separating from the clay when heating and cooling. That's why I'm using grog, rather than sand. Sounds like your clay is well grogged - can you find out what percentage grog it is?

Here's a link to someone who's done similar with a grog, clay and fireclay mix: Backyard Boulangerie I'm copying parts of this design, while trying to add a few improvements too.

Carl
__________________

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

Last edited by Carl; 11-29-2007 at 12:47 PM. Reason: Wrong link!
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Red Clay Brick Oven in the Philippine Islands jayjay Introductions 86 04-10-2013 04:47 PM
Heat-dry mortar made of refactory clay and refactory sand (and nothing else) Frances Pompeii Oven Construction 11 06-25-2011 03:09 PM
Single Wall Black Pipe... aeneas1 Design Styles, Chimneys and Finish 7 11-05-2006 05:52 AM
Clay cooker technique in 36" Tuscan Fudugazi Get Cooking 1 08-28-2006 11:17 AM
Clay Pots and Pizza hilltop Newbie Forum 5 04-19-2006 06:05 AM


All times are GMT -7. The time now is 08:00 AM.

Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0
2006/10 Forno Bravo, LLC