42" in Hungary by Slovak guy ;)

[alex.g]

Re: 42" in Hungary by Slovak guy

Mine entrance is 'only' slightly over 10inches height, do you think it is ok, please?

[ggoose]

Re: 42" in Hungary by Slovak guy

Should be just fine; mine is 11-ish...just can't cook any fat turkeys!

[alex.g]

Re: 42" in Hungary by Slovak guy

Great.
Please how many sq feet or sq meters of ceramic insulation is needed for one layer?
I would cover 1" and 1"

[alex.g]

Re: 42" in Hungary by Slovak guy

Update

[Steellearning]

Re: 42" in Hungary by Slovak guy

Great.
Please how many sq feet or sq meters of ceramic insulation is needed for one layer?
I would cover 1" and 1"

I'm going out on a limb here since i haven't insulated my oven yet, but I purchaced 3 x 7,3 meters for 3 layers, the rolls are 2,5 x 61 cm, and I'll most likely have to much. So my guess would be get one roll of 7,3 meters.

[alex.g]

Re: 42" in Hungary by Slovak guy

hm.. dont think, coz
https://www.fornobravo.com/PDF/FB_blanket.pdf

"Each Forno Bravo oven comes with 50 sq. ft. of FB Blanket, enough to cover the oven with at least a 1" thick layer.

Mechanical
Size: 25’x24”x1”
Volume: 50 sq. ft.
Weight: 37.0 lbs.
Covers a 42” wood oven dome with one layer."

50 sq f is 4.64 sq m.

Locally it is
Cerablanket 1260?C 25x610x7320 mm OH 130 kg/m3 (one package 4,47 m2) Price:14,55 EUR/m2

so in best you need 2 packages to cover it once

[Steellearning]

Re: 42" in Hungary by Slovak guy

hm.. dont think, coz
https://www.fornobravo.com/PDF/FB_blanket.pdf

"Each Forno Bravo oven comes with 50 sq. ft. of FB Blanket, enough to cover the oven with at least a 1" thick layer.

Mechanical
Size: 25?x24?x1?
Volume: 50 sq. ft.
Weight: 37.0 lbs.
Covers a 42? wood oven dome with one layer."

50 sq f is 4.64 sq m.

Locally it is
Cerablanket 1260?C 25x610x7320 mm OH 130 kg/m3 (one package 4,47 m2) Price:14,55 EUR/m2

so in best you need 2 packages to cover it once

Looks like I'll need some more...

[alex.g]

Re: 42" in Hungary by Slovak guy

raw calculation of the surface area without entrance is - 8.5 m2

[alex.g]

Re: 42" in Hungary by Slovak guy

it is already
Google formulae

Switch to m2 and you will see

Other problem is, ceramik blanket here is not a cheap thing, 5 rolls (~4.5 m2 each) of 25mm thickness (1 inch) would cost 300EUR

[gorazdr]

Re: 42" in Hungary by Slovak guy

You can use this Wired Mat WM 640 GG | Knauf Insulation Technical Solutions it works well and I am shure you can get it in Hungary. Price 18? roll.

[Steellearning]

Re: 42" in Hungary by Slovak guy

it is already
Google formulae

Switch to m2 and you will see

Other problem is, ceramik blanket here is not a cheap thing, 5 rolls (~4.5 m2 each) of 25mm thickness (1 inch) would cost 300EUR

It costs even more here in Norway... hate to buy more if I don't have to.
This is how I've been thinking and I must be doing something wrong with my math

My 42 inch oven has a outside radius 58,5 cm. For the sake of keeping it simple
say r=59 cm. If I put that in the sphere calculator I get 4.37 m2.
Because its only half a sphere shouldn't we divide that number by 2 and get 2.19 m2.
I used this calculator
Sphere Calculator

[alex.g]

Re: 42" in Hungary by Slovak guy

did you use it? How thick?

[alex.g]

Re: 42" in Hungary by Slovak guy

you are right only >2 m2

Rock wool.. anyone tried it? Really cheaper and Lambda seems like on par

[Steellearning]

Re: 42" in Hungary by Slovak guy

you are right only >2 m2

Rock wool.. anyone tried it? Really cheaper and Lambda seems like on par

According to reps from Rockwool here in Norway, Rockwool contains a binder that disintegrates after repeated high temp heatings. Ceramic blankets do not use binders they are woven together. But I'm really not sure if its a problem with these ovens.

[alex.g]

Re: 42" in Hungary by Slovak guy

Nobasil WM 660 GG here in Slovakia from Knauf is marked up to 660C
From what i read dome top can reach 1000F (537C)

trying to call there and find out of 660C is ok for onetime heat or it can reach 600 everytime with no damadge

Maybe then it is wise to cover 1 inch ceramic and then that rockwool?