#11  
Old 12-02-2013, 10:27 AM
Serf
 
Join Date: Nov 2013
Location: topsfield, ma
Posts: 14
Default Re: Vermiculite:Cement ratio

What type of vermiculite is recommended ( with cenent) for over dome as insulation ?

I gave the larger granular 'A4'

Ed
Reply With Quote
  #12  
Old 12-02-2013, 03:07 PM
UtahBeehiver's Avatar
Il Pizzaiolo
 
Join Date: May 2012
Location: Utah
Posts: 1,557
Default Re: Vermiculite:Cement ratio

Ed,

A4 I believe is coarse grade used typically for packing. IHMO, it will work fine but you may have to make the cement/verm ratio richer to get good particle adhesion. Best way, try a couple small sample batches, ie 1 cement 5 verm. What are you going to render the insulation with?
__________________
Russell

Experiences are the names I call my mistakes!

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


My Picassa Picture Log
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Reply With Quote
  #13  
Old 12-02-2013, 03:27 PM
Serf
 
Join Date: Nov 2013
Location: topsfield, ma
Posts: 14
Default Re: Vermiculite:Cement ratio

What do u mean by 'render'?

I will use Portland cement with the vermiculite.

Thinking of a ratio of about 5:1 , V:PC or 6-7:1
Reply With Quote
  #14  
Old 12-03-2013, 07:10 AM
UtahBeehiver's Avatar
Il Pizzaiolo
 
Join Date: May 2012
Location: Utah
Posts: 1,557
Default Re: Vermiculite:Cement ratio

Stucco (render) over the vcrete.
__________________
Russell

Experiences are the names I call my mistakes!

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


My Picassa Picture Log
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 12-03-2013, 01:35 PM
cobblerdave's Avatar
Il Pizzaiolo
 
Join Date: Jan 2010
Location: brisbane australia
Posts: 1,995
Default Re: Vermiculite:Cement ratio

Gudday
You can get a good finish on V-Crete anyway by a combination of patting it down and smoothing it over with a steel float. A coat of cement paint and its waterproof. Sometimes we go a bit overkill in our constructions being DIYers.
Regards Dave
__________________
Measure twice
Cut once
Fit in position with largest hammer

My Build

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

My Door

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Reply With Quote
  #16  
Old 12-06-2013, 03:26 AM
david s's Avatar
Il Pizzaiolo
 
Join Date: Mar 2007
Location: Townsville, Nth Queensland,Australia
Posts: 4,518
Default Re: Vermiculite:Cement ratio

The finer grade is a bit easier to work, but requires more water which needs to be removed after it's set. I use a medium grade and have found a 50/50 mix of perlite and vermiculite makes a more workable mix than either alone, can't explain why. Also a little clay added helps make a more workable mix. I use about half a handful per litre of cement.

Last edited by david s; 12-06-2013 at 03:28 AM.
Reply With Quote
  #17  
Old 12-07-2013, 01:04 AM
Apprentice
 
Join Date: May 2013
Location: Ireland
Posts: 152
Default Re: Vermiculite:Cement ratio

For the dome I had to increase the water quite a bit to make the vermicrete workable and stop it just crumbling away.
Reply With Quote
  #18  
Old 12-07-2013, 03:48 AM
cobblerdave's Avatar
Il Pizzaiolo
 
Join Date: Jan 2010
Location: brisbane australia
Posts: 1,995
Exclamation Re: Vermiculite:Cement ratio

Quote:
Originally Posted by david s View Post
The finer grade is a bit easier to work, but requires more water which needs to be removed after it's set. I use a medium grade and have found a 50/50 mix of perlite and vermiculite makes a more workable mix than either alone, can't explain why. Also a little clay added helps make a more workable mix. I use about half a handful per litre of cement.
Gudday
Interesting point about adding clay to the mix, anything to make it easier to work with . A lot like fireclay in the "homebrew" mortar ?
I also understand how adding vermiculite would fill up the spaces in-between the spheres of pearlite.
Regards dave
__________________
Measure twice
Cut once
Fit in position with largest hammer

My Build

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

My Door

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Reply With Quote
  #19  
Old 12-19-2013, 08:01 AM
Apprentice
 
Join Date: May 2011
Location: UK
Posts: 168
Default Re: Vermiculite:Cement ratio

We created an enclosure around the dome, wrapped the dome in a 4" thick layer of fire blanket and filled the enclosure 6" above the dome with vermiculite.

The oven keeps hot until the following afternoon.
Reply With Quote
  #20  
Old 12-19-2013, 12:20 PM
david s's Avatar
Il Pizzaiolo
 
Join Date: Mar 2007
Location: Townsville, Nth Queensland,Australia
Posts: 4,518
Default Re: Vermiculite:Cement ratio

For those working with vermicrete, because it takes so much water there is way more than is required for the hydration process, so I never bother to cover it. The greater problem is trying to remove the water safely. It is easier to allow sun and wind to do much of this if the conditions are right and you can afford the time. See attached experiment.
Attached Files
File Type: zip Vermicrete insulating slab copy.doc.zip (73.2 KB, 26 views)
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
? on ratio of vermiculite to cement toddlungman Pompeii Oven Construction 4 12-06-2013 03:22 AM
Hearth Height and operator ratio science! Xabia Jim Modular Refractory Oven Installation 39 01-12-2011 06:11 AM
Concrete Mix ratio fxpose General Building and Construction 8 02-21-2010 09:36 AM
Recommended insulating concrete ratio? kebwi Tools, Tips and Techniques 1 09-24-2009 09:14 PM
infrared laser thermometers Dutchoven Tools, Tips and Techniques 21 04-23-2008 09:55 AM


All times are GMT -7. The time now is 07:23 AM.

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