Go Back   Forno Bravo Forum: The Wood-Fired Oven Community > Pizza Oven Design and Installation > Pompeii Oven Construction

Like Tree4Likes

Reply
 
LinkBack Thread Tools Display Modes
  #11  
Old 02-15-2013, 11:48 PM
Laborer
 
Join Date: Oct 2012
Location: Loomis, CA
Posts: 66
Default Re: Share your crack stories

Thanks for the input. The foundation, slab and heart are solid with no cracks. No expansion joints or cracks in the floor. So i am ruling out the expansion joint in the foundation theory The crack appeared in rows 1-3. I have fired twice and the gap has not grown. The rest of the dome appears very solid with not evidence of any cracks. I am baffled by this crack since my dome is be floating on the brick floor. Maybe the mortar outside shell adhered to the base and prevented the dome from expanding and floating as temperatures changed. Just trying to learn and understand the WFO build process.
Reply With Quote
  #12  
Old 02-17-2013, 04:24 AM
Master Builder
 
Join Date: Jan 2013
Location: Japan
Posts: 610
Default Re: Share your crack stories

It does not make any sense.
Your dome is built on top of the floor--
If you initially put anything down, even a sheet of newspaper that would prevent the brick dome from sticking to the hearth firebrick; and the hearth firebrick not mortared down in anyway--except for a possible sand and fireclay slurry...

Everything should be able to move freely with expansion.

Further, you have several layers of ceramic blanket insulating the dome--so no direct contact to your outer render.. Here nothing to restrict movement...

Possibly ceramic fiber is not what it is cracked up to be! Maybe it allows masonry to heat up in excess too quickly? Where perlite vermiculite moderate the heat up? But that discussion does not help your situation!

The real guys in the know who could answer these questions need to help here.
Right now simple reasoning from another newbie isn't producing any acceptable answers.. Except..possible normal expansion and drying, cracks that do not show up until extended usage and not to worry about! But just a guess.. mine isn't even fired once and I'm doing everything against better advice!

Keep asking--the pros will surely step in to assist!
Reply With Quote
  #13  
Old 02-17-2013, 04:51 AM
david s's Avatar
Il Pizzaiolo
 
Join Date: Mar 2007
Location: Townsville, Nth Queensland,Australia
Posts: 4,885
Default Re: Share your crack stories

Almost all ovens and kilns have some cracks. Wood fired ovens are heated way too fast for the refractory to cope with the expansion that takes place. Around 300 C per hour. The industry standard for kilns is 100 C per hour. Firing with wood is way harder to control than oil, gas or electricity. The crown of the dome and the centre of the floor are heating up way faster than the outer perimeter. I think that is why the cracking starts down there. Also it is the weakest part of the dome.if you want to be kind to your refractory then take it slow, but nobody really wants to do that. We tend to try to get it to temp as fast as possible,a hence we have some cracks.
Reply With Quote
  #14  
Old 02-17-2013, 07:27 AM
stonecutter's Avatar
Il Pizzaiolo
 
Join Date: Jun 2007
Location: South Carolina,USA
Posts: 1,930
Default Re: Share your crack stories

Quote:
Originally Posted by brickie in oz View Post
I used to work in a bricklaying gang where one guy used to always have his crack showing as he bent forwards, every time you turned around you got an eye full, he thought it was hilarious until I started flicking mortar at his crack.

He never did cover it up though.
I nicknamed him Crackers.
This reminded me of a guy I worked around a while back. Same problem and no matter how hard you tried not to see...you did.

We called him spackle. More of a sheetrocker term but you get the idea.
brickie in oz likes this.
__________________

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


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


When we build, let us think that we build for ever.
John Ruskin

Last edited by stonecutter; 02-17-2013 at 01:43 PM.
Reply With Quote
  #15  
Old 02-17-2013, 08:41 AM
Laborer
 
Join Date: Oct 2012
Location: Loomis, CA
Posts: 66
Default Re: Share your crack stories

Mikku-

I think you may have identified the source of my mysterious crack. I attached the first row with a thin layer of mortar. I also mortared the joints and back using a heavy coat of Mortar.

Brian
Reply With Quote
  #16  
Old 02-17-2013, 03:16 PM
Master Builder
 
Join Date: Jan 2013
Location: Japan
Posts: 610
Default Re: Share your crack stories

I don't know if that is the cause, probably more likely the firing thing--your floor bricks are still movable right? Probably a combination of everything! The pros would know, just have to get their attention!

Now you need to work on the fix... As brickie and stonecutter suggest, maybe you need to work 20 or 30 years perfecting the technique of flicking mortar with a great deal of accuracy. Then you can do your repairs successfully by filling the cracks when they unexpectantly appear--without even having to get inside the oven! But try to keep your eyes peeled for the occasional "full moon". That is the most difficult to get out of your mind!

All joking aside, keep asking the pros... or maybe better yet, search the archives--you never know what is there until you look deeper. That way, you keep the "wolf" at bay! So it can answer more important questions???
Reply With Quote
  #17  
Old 02-17-2013, 03:34 PM
Master Builder
 
Join Date: Jan 2013
Location: Japan
Posts: 610
Default Re: Share your crack stories

Quote:
Originally Posted by stonecutter View Post
This reminded me of a guy I worked around a while back. Same problem and no matter how hard you tried not to see...you did.

We called him spackle. More of a sheetrocker term but you get the idea.
Wouldn't "moon beam", "high beam", "low beam", "running lights", or "harry" be better? At least it would be more descriptive of "phases of the moon?"

Yuck! Don't get me going, have touble sleeping as it is!
Reply With Quote
  #18  
Old 02-17-2013, 03:57 PM
stonecutter's Avatar
Il Pizzaiolo
 
Join Date: Jun 2007
Location: South Carolina,USA
Posts: 1,930
Default Re: Share your crack stories

Quote:
Originally Posted by mikku View Post
Wouldn't "moon beam", "high beam", "low beam", "running lights", or "harry" be better? At least it would be more descriptive of "phases of the moon?"
No.


He never showed his whole posterior, which nullified any term given to full exposure, and as for the extent of hair covering said posterior, I never cared to look longer than a millisecond.

The nickname was not only a name....it was a suggestion. Like this, "You need some spackle, Spackle."

In his case, the name was perfect. And it never ceased to produce belly laughs from everyone...except him of coarse. You would think he would buy longer tailed shirts...oh well.
__________________

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


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


When we build, let us think that we build for ever.
John Ruskin

Last edited by stonecutter; 02-17-2013 at 05:39 PM. Reason: typo
Reply With Quote
  #19  
Old 02-17-2013, 05:33 PM
Master Builder
 
Join Date: Jan 2013
Location: Japan
Posts: 610
Default Re: Share your crack stories

or a size bigger pants, suspenders or a belt!
Reply With Quote
  #20  
Old 02-17-2013, 11:17 PM
Laborer
 
Join Date: Oct 2012
Location: Loomis, CA
Posts: 66
Default Re: Share your crack stories

I think I will just fire it and bake another pizza. If I have a complete dome failure it will probably be speculator. I will post a picture of my dilemma shortly.
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
crack in the dome myg80oven Modular Refractory Oven Installation 3 04-20-2014 12:09 AM
obligatory crack photo dougrappe Pompeii Oven Construction 7 07-01-2009 07:16 AM
Exterior crack JAG Design Styles, Chimneys and Finish 3 02-23-2009 11:23 PM
crack in top of over ross Pompeii Oven Construction 3 08-20-2008 12:31 PM
Oven crack ginoamato Newbie Forum 2 08-15-2008 08:04 PM


All times are GMT -7. The time now is 10:23 PM.

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