Some questions about the isolation

[maurilein]

Hello,

i am from Germany and i have some questions about the isolation.

1. Vermiculite, which they are selling here in germany, is a stuff for: botanical, firecracker e.t.c.
Are there differrent types of vermiculite, or is it the same vermiculite you are using?

2. Vermiculite Cement mixture:
Is it nescessary to use a special fireproof cement for the vermiculite-cement mixture, or can i take the usual cement like i used for the baseplate

3. Between vermiculite/cement mixture and firebricks
Can i use sand, between vermiculite/cement mixture and the baseplate-firebricks.
If yes, what kind of sand ? And how many inches high must it be?


hope you understand me :-)

kind regards

[Frances]

Re: Some questions about the isolation

Hi maurilein, welcome to the forum!

Whereabouts in Germany are you?

1. The Vermiculite for botanical use will be fine for your oven.

2. You can use regular cement... but make sure you use cement, and NOT concrete or mortar, which are premixed products with sand/gravel mixed in.

3. You're supposed to use fireclay and sand... but I used just sand and some dust I got from cutting the firebricks. Any clean sand will do. You just need to put a thin layer of sand on, maybe 1 cm, to even out the Vermicultite layer and so that you can tap the bricks into a level position.

hope you understand me :-)

No problem ... but if you have any translational issues during your build, I'd be glad to help out. I've been through the whole finding-the-equivalent-German/Swiss-product thing here, and its not always easy.

[maurilein]

Re: Some questions about the isolation

Hoi Frances,

thank you for your answer.

I live near the swiss boarder.
We are neighbours

Allschwil --> Bad S?ckingen ... 37 minutesd by car.


channi dir mol all?te ?

[maurilein]

Re: Some questions about the isolation

which grain size from vermiculite i have to use?

0 - 5 mm
5 - 10 mm
2 - 3 mm


???

[Frances]

Re: Some questions about the isolation

I think most people use the 2-3 mm. Due to some misunderstandu?ng I actually ended up with the 5-10 mm... but that also works perfectly well.

[Frances]

Re: Some questions about the isolation

Hey Maurilein, I must be really slow, but could you use any leftover materials?

I've still got these and a couple of firebricks:
http://www.fornobravo.com/forum/f40/...iles-3134.html

You'd be more than welcome to them, just let me know.

[maurilein]

Re: Some questions about the isolation

Hy Frances,

i will call you soon...

- My dome will be 105 cm inside.
- The isolation under my firebrick will be a 8 cm vermiculite/cement mixture.
- When the dome is done i will make a wall around it. Inside i fill out also with Vermiculite.


What do you think, how many Liters of Vermiclite i will need +-
Are 2 x 100 Liter Packs enough ?

[dmun]

Re: Some questions about the isolation

- The isolation under my firebrick will be a 8 cm vermiculite/cement mixture

102mm (4") of vermiculite cement is recommended. If you are space limited, go with the refractory insulation boards like cal-sil or mineral fiber board.

[maurilein]

Re: Some questions about the isolation

Hi,

there is no space limit. The cement-boardplate is not finished, i will do it on this saturday. If 4" for the vermiculite-cement are recommended, i can do it.