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

Like Tree5Likes

Reply
 
LinkBack Thread Tools Display Modes
  #11  
Old 07-28-2012, 09:33 PM
Peasant
 
Join Date: May 2012
Location: Rockford, IL
Posts: 29
Default Re: Shaping vermiculite concrete dome

How soon does the mixture start to cure? How much should I try to compact the mixture with my hands? So far I have seen very little signs of curing, I am used to concrete no longer being workable after less than an hour.
Reply With Quote
  #12  
Old 07-28-2012, 11:50 PM
david s's Avatar
Il Pizzaiolo
 
Join Date: Mar 2007
Location: Townsville, Nth Queensland,Australia
Posts: 4,515
Default Re: Shaping vermiculite concrete dome

It should be firm in 24 hrs. You'll be able to easily crumble it away, but all you need is a surface that is sufficiently strong enough to render/stucco on to. Dry it out well before doing this though.
Reply With Quote
  #13  
Old 08-26-2012, 12:13 PM
Laborer
 
Join Date: Aug 2011
Location: Vienna, Virginia
Posts: 59
Default Re: Shaping vermiculite concrete dome

I came across this thread while looking for information on using vermiculite concrete as a basecoat for stucco on my dome, and thought I would pass on this chart that I found on the Schundler Vermiculite Concrete site. It may be useful for those wondering (as I did) about different mixes and relative strength.
Attached Files
File Type: pdf Vermiculite Concrete.pdf (30.7 KB, 249 views)
videts38 likes this.
Reply With Quote
  #14  
Old 08-26-2012, 05:13 PM
lwood's Avatar
Master Builder
 
Join Date: Jul 2009
Location: philippines
Posts: 642
Default Re: Shaping vermiculite concrete dome

The most important value is missing, the "R" value. Hundreds of ovens have been successfully built on top of the 7 or 8:1 mix, as long as it is properly supported. The dome certainly is not structural. The vermicrete will crumble to the touch 24 hrs after. So be careful when you remove your forms. I gave it 3 or 4 days before messing with it. It firms up nicely and proceed. It's structural properties are not a concern here, insulation is the issue....the more the better.
__________________
Our Facebook Page:
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Reply With Quote
  #15  
Old 08-27-2012, 11:32 AM
Neil2's Avatar
Il Pizzaiolo
 
Join Date: Oct 2006
Location: Vancouver Island
Posts: 1,374
Default Re: Shaping vermiculite concrete dome

Here is the screed I used for shaping the vermicrete layer (12:1 mix):
Attached Thumbnails
Shaping vermiculite concrete dome-oven-insulation.jpg  
Gulf, videts38 and sdsrn like this.
Reply With Quote
  #16  
Old 08-27-2012, 06:27 PM
Gulf's Avatar
Il Pizzaiolo
 
Join Date: Sep 2011
Location: Mississippi
Posts: 1,398
Default Re: Shaping vermiculite concrete dome

Quote:
Originally Posted by Neil2 View Post
Here is the screed I used for shaping the vermicrete layer (12:1 mix):
Neil2,
That's it!! I've been wondering where I got the idea for my template . I scoured builds for a couple of years before taking the plunge. I know that I read yours start to finish, as I did many others, only making mental notes.
Thanks Neil.
__________________

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



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



To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Reply With Quote
  #17  
Old 10-29-2012, 06:24 AM
Serf
 
Join Date: Oct 2012
Location: Texas
Posts: 8
Default Re: Shaping vermiculite concrete dome

Here's the rank beginner's question ... the install instructions on my modular kit say to wrap the insulation banket, cover in wire and then the finish coat ... NOTHING about a layer of vermiculite concrete???
Reply With Quote
  #18  
Old 10-29-2012, 01:35 PM
david s's Avatar
Il Pizzaiolo
 
Join Date: Mar 2007
Location: Townsville, Nth Queensland,Australia
Posts: 4,515
Default Re: Shaping vermiculite concrete dome

You don't have to do a vermicrete layer over the blanket, but it evens out all the lumps and bumps where the blanket overlaps and folds. Your outer rendered shell would otherwise be overly thick to get back to a nice hemispherical form. Your common sense tells you the mix is too crumbly and it won't set, but wait 24 hrs and it will. Not really strong, but good enough to render up against. Adding more cement just reduces the insulation value.
Reply With Quote
  #19  
Old 10-29-2012, 03:15 PM
Serf
 
Join Date: Oct 2012
Location: Texas
Posts: 8
Default Re: Shaping vermiculite concrete dome

THANK YOU David ...makes perfect sense. I am determined to get this right, thinking theres not going to be much of a 'do-over' space
Reply With Quote
  #20  
Old 11-06-2012, 03:43 AM
Serf
 
Join Date: Feb 2011
Location: Apollo Bay, Australia
Posts: 3
Default Re: Shaping vermiculite concrete dome

Thank for the heads up David! This step was confusing me and I haven't even received my Casa yet.....
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
Can I use insulating vermiculite concrete instead of mortar clading waynebergman Pompeii Oven Construction 4 12-30-2009 06:20 PM
is it possible to make the dome entirely of a concrete vermiculite mix? muckrunner Tools, Tips and Techniques 3 08-26-2009 11:13 PM
TIP: Mixing Vermiculite Concrete cvdukes Tools, Tips and Techniques 12 04-25-2009 10:29 AM
Vermiculite Concrete hearth insulation jrparks Pompeii Oven Construction 4 01-09-2009 03:35 PM
Curing Concrete and Masonry Xabia Jim Tools, Tips and Techniques 21 03-31-2008 02:15 PM


All times are GMT -7. The time now is 12:55 AM.

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