Vermicrete over Blanket

[tdibratt]

Hi folks I am at the stage of putting the blanket on the dome. I have been reading the forum and just want to make sure I get this right based on peoples experiences.

I plan on putting some foil paper over the dome which has been parged with about 1 inch of high heat mortar. Then cover the foil with the blanket. Then put about 2 inches of vermicrete over the blanket. Does this approach sound right?

Questions:
1. How do I get the blanket to stay on?
2. Looks like people use chicken wire over the blanket as a lathe. Would cermamic tile lathe do or are the holes too small? Do I need a lather at all?
3. Next the vermicrete is 2 inches OK or should I go more? I saw someone post that they did a mix of 1/2 fireclay, 1 cement and 5 vermiculite to make it stickier. Is that a good mix?
4. Should I not be concerned that the blanket is getting covered by a wet substance? Won't the blanket getting wet cause a problem? Or should I cover it with foil as well before the vermicrete?

Thx

[christo]

Re: Vermicrete over Blanket

I did not parge much of my dome. I was trying to get as fast a heat up as possible and wasn't too worried about baking.

I also did not use foil to cover the dome.

As a result my blanket pretty much stuck to the dome. I'm not sure the foil is necessary.

I ran some galvanized wire across the dome in a crisscross pattern to keep it in place.

any left over pieces of the blanket were used to cover once again the top 2/3rds of the oven.

If you can, I'd go a little thicker on the vermicrete - seems that there is never enough insulation!

Christo

[nissanneill]

Re: Vermicrete over Blanket

Hi tdibratt,
it sounds like you have been reading my build as I went through everything except the foil with my build.
Read:
http://www.fornobravo.com/forum/f21/...-4-a-2045.html

permalink #8 to answer all of your queries. Also hints and tips on getting that difficult cement to work and stick!
As far as the blanket getting wet, the vermiculite cement although a paste consistency will not 'soak' the blanket and will easily dry out especially if you cure your oven properly and carefully.
I would not touch the foil as it will not permit a bond with the oven and constituents but leave a potentially weaker thin shell around it.
I can see it serve absolutely no usefull purpose, only make your life difficult.

Neill

[thebadger]

Re: Vermicrete over Blanket

Tdibratt,

I don't think the foil is necessary. Here's what I did,

• Put the Blanket directly on the dome - you'll be surprise how well it stays on.
• I then used a little wire to keep it place but probably wasn't necessary.
• I did use chicken wire to help keep the shape and hold the perlcrete (like vermicrete)
• I used 2 " of blanket (3" on top) and 3-4" of perlcrete
• Stick to 5 parts of portland an 1 part vermiculite - you'll be fine.
• The blanket will dry out - no worries

Good luck.
Dick

[toddj]

Re: Vermicrete over Blanket

Tdibratt,

Stick to 5 parts of portland an 1 part vermiculite - you'll be fine.

Dont you mean Stick to 1 parts of portland an 5 part vermiculite ??

.