#1  
Old 05-07-2008, 05:06 AM
Laborer
 
Join Date: Jul 2007
Location: Nottingham
Posts: 66
Default Vermicrete - adding Sodium Silicate

Just a quick note on an 'experiment' I tried at the weekend.

I took a standard mix of 2L OPC, 3L Water and 10L of vermiculite and added about 250ml of 75% Sodium silicate solutoin. I used the advised way of mixing the OPC and water first, then added the sodium silicate and finally the vermiculite.

Within 3 hours the mix had firmed up dramatically, and within 24hrs it had become very firm. This is in contrast to the last lot I made which took 5 days to go off properly, and still didn't completly set up as I would like it.

Sodium Silicate is used in refractory mixes, and its certainly something I would recommend if anyone has an easy source - obviously, I'd be interested to see how anyone else gets on !

Cheers

Peter
Reply With Quote
  #2  
Old 05-07-2008, 11:30 AM
Apprentice
 
Join Date: Apr 2007
Location: UK
Posts: 100
Default Re: Vermicrete - adding Sodium Silicate

I used water glass (sodium silicate) in my oven - I used it to make a mouldable insulation mix, because the sodium silicate will withstand much higher temperatures than portland cement, and it sets much quicker than a pure portland mix.

A couple of my posts on sodium silicate:

http://www.fornobravo.com/forum/3/an...html#post27142 (Another UK oven started)

http://www.fornobravo.com/forum/8/fi...html#post30664 (Is fireclay necessary?)

A good link to using it for refractory mixes is here:

Perlite/silicate composites

There's a bit more detail on my blog too, on how I used the insulation mix to coat the inside of my chimney to round off some rough edges. I'll be using the same mix to make the door.

Carl
__________________

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Reply With Quote
  #3  
Old 05-07-2008, 11:32 AM
Apprentice
 
Join Date: Apr 2007
Location: UK
Posts: 100
Default Re: Vermicrete - adding Sodium Silicate

Should have added - I bought my sodium silicate from clayman supplies - link here: Miscellaneous Medias & Materials

Carl
__________________

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Reply With Quote
  #4  
Old 06-01-2008, 04:35 AM
david s's Avatar
Il Pizzaiolo
 
Join Date: Mar 2007
Location: Townsville, Nth Queensland,Australia
Posts: 4,720
Default Re: Vermicrete - adding Sodium Silicate

Carl,
Thanks for the sodium silicate info. I use it for slip casting. That is a thick mixture of clay and water that is solid enogh to pick up in a handful. When you add a small quantity (30 ml or so) of sodium silicate to a bucket full of this slip, once you start to mix it the whole bucket becomes quite liquid like pouring cream, without having to add more water, which is what you want to get rid of into the plaster mould. Magic stuff.
Reply With Quote
  #5  
Old 01-22-2009, 02:21 AM
Serf
 
Join Date: Jan 2009
Location: india
Posts: 1
Default Re: Vermicrete - adding Sodium Silicate

i am intrested in making small moulded articles of vermiculite, can you plz suggest me method to make such article with sodium silicate as binder. after making taking mould out , do we require to heat up the moulded article.
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



All times are GMT -7. The time now is 12:43 AM.

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