Pizza History in the Hammer Continues

[Ope-dog]

Hey Barry, I wanted to check in and see how you were getting on with the vermiculite layer.. more specifically, if you were going to loose fill your enclosure or do a mix and hard coat? I started my v/p layers yesterday. I will fully admit.. my least favorite part of the entire build thus far. Man, that stuff is obnoxiously onery to work with!!! lol

[MarkJerling]

Forno Friends!

Well - moving on to the insulation of the dome!
The vent assembly is complete and the smile on my face is genuine!!
I'm very happy with it - wow.

Starting the insulation - at 3 layers (3") at this point and ran out (working from one full roll and a bag of scraps from my friend who owns a refractory company.
I have about a 2' x 7' swath to complete the 3 layers all round and he is going to let me steal more scraps! Wooo!

QUESTION: can I be content with 3" of blanket knowing I will be building an enclosure and filling it with vermiculite all around inside? Should it be 4"?
FB plans suggest 1' and 3 (4cu ft) bags of vermiculite or 2 50ft rolls ...?
It seems the accepted thickness of blanket on the forum appears to be 4" ... should I shoot for that with the 4" layer of loose vermiculite that will be on top in the enclosure? Too much?

Not sure what the sweet spot is? Help!
Barry

Looking great Barry!

[GFI]

Hi Barry, by the way, I know you were going to Elvis for Vermiculite...you can also order Perlite from the big orange store. Just over $60 for 4 cu ft delivered to your house. I'm going to do the 50/50 Vermiculite/Perlite mix. The Perlite was delivered today. Bit less than a week delivery.
glenn

[Petter]

The optimum 1:1 ratio mass:insulation is only valid for a fix wall thickness. Like if you shall do a casting and your stand is already built or you just want to minimize the oven footprint.

More insulation is allways better. But sometimes you are restricted.

Since your bricks are fix, one could say that anything under 4.5" insulation is non-optimized. You gain performance all the way up to about 1:4 in thickness ratio, I.e. Point of disminishing return.

Your plan of doing 3 + 4 is very good.

[SableSprings]

You've done a fabulous job Barry & your build will be referred to often. I never thought about a ratio of covering insulation to actual brick thickness. I just have always gone with the standard 2-4" of batting is plenty for heat retention. Once fully cured & with all that insulation, you'll be able to cook/bake for days after a pizza party! Soon you'll finally be enjoying the fruits (well, more likely pizza ) of your labor.

[Baza]

Thank you Friends!

Very appreciative of your input on the next steps. Unfortunately, this is one of those moments when the engineers on the forum eclipse the plonkers like me!
The best I can understand from reading the data is that a 1:1 ratio is best? So, if the brick is 4.5" thick, the insulation should be too?
Yet others feel the blanket insulation is deemed TOO thick in that ratio by some. It is such good info lost on me! ARG.
Petter I am grateful for your sharing - I'll return to it and try to understand more!
CapePizza I think your experience here is helpful to my build.

Given I will be enclosing the structure and filling the enclosure with vermiculite (as many of you use vermicrete to finish, thermally and aesthetically, your domes) I believe 3" of blanket and 4+" of vermiculite all around should do the thermal job. That is my hope in a world where I don't complete understand the physics/science of thermal materials - but am SO appreciative of the door opening by those that chimed in!

Thank you
Barry

[NCMan]

Looking good, great job!!

[CapePizza]

Hello Barry.... FWIW, I put 3 layers of 1 inch blanket, wire lathe, and about 3 inches of perlcrete mix over that. If you haven't seen this FornoBravo YouTube video on applying the insulation, it's well worth a watch. I found it very helpful. https://youtu.be/Lq4lpzK-uFQ. Also, FWIW, I'm finding if I cook pizza one night, getting the oven up to 800+ degrees, the next day it's still around 450-500 and the day after that around 250. It's really very cool the way it retains the heat.
Your oven is looking great!
John

[Petter]

Great work!

insulation thickness:
https://community.fornobravo.com/for...retic-apporach

pick your choice.

[Baza]

Forno Friends!

Well - moving on to the insulation of the dome!
The vent assembly is complete and the smile on my face is genuine!!
I'm very happy with it - wow.

Starting the insulation - at 3 layers (3") at this point and ran out (working from one full roll and a bag of scraps from my friend who owns a refractory company.
I have about a 2' x 7' swath to complete the 3 layers all round and he is going to let me steal more scraps! Wooo!

QUESTION: can I be content with 3" of blanket knowing I will be building an enclosure and filling it with vermiculite all around inside? Should it be 4"?
FB plans suggest 1' and 3 (4cu ft) bags of vermiculite or 2 50ft rolls ...?
It seems the accepted thickness of blanket on the forum appears to be 4" ... should I shoot for that with the 4" layer of loose vermiculite that will be on top in the enclosure? Too much?

Not sure what the sweet spot is? Help!
Barry

[Baza]

Hey Forno Friends!

The LAST BRICK was laid today!!
Completed the Chimney assembly now that the base transition is in place on the vent arch.
Lots of cuts here - but happy with the result.

1. First set of bricks were cut out the depth of the chimney plate much as Utah and Modified9v did. Ground down to be flush when the plate is put on.
2. Plate put in place - happily the mortaring on the base transition ensured the plate is level. I asked about mortar to hold the plate on to this level (or silicone) - general consensus was not to as the silicone - under heat - would likely fail here and there is no space for mortar underneath (also allows for some expansion)
3. Cut full bricks in half length wise: 2 bricks made 4 thin 1/2 bricks. Cut out the space around the flange with enough room for chimney. Mortared down this last layer over the plate - cleaned out the space around the flange.

Test fit the chimney and all worked out! Very happy!

[Baza]

Hello Forno Friends!!

Been a good week! The oven vent assembly has been an adventure and though having to wing some of it (particularly given a poorly made form for the arch) the learning I took from many here in this forum got me through. I wanted simplicity moving up to the chimney and blended some learning from a number of folks here. Fewer bricks was my goal (segmented arch driving that decision)
So - determined to make the base in three layers: FIRST - level base that closes the throat from 10" interior vent to 8" at plate face; SECOND - ground out brick for plate base; THIRD - brick mortared on top of the plate to keep the assembly in place: Utah, Mongtoa, Modified9v, Dino_Pizza and all the lurks I did on many builds helped here.

These pics show the first level base to close the throat to 8" square. Lots of cuts and grinds - but very happy with the result - I hope the smoke travels the route that was painstakingly crafted for it!
Fingers crossed - ha!

[Baza]

Neil.B great to hear from you mate!!! Things are coming along and now that I’m finished watching the Giro stage I’m going out now to finish the chimney plate assembly and test it out, put insulation on dome and see where I land!!

mom hoping next week to possibly start some curing fires - but I’m very one-thing-at-a-time in my method and may do the steel framing before the curing so I can focus on the curing as it appears a delicate, slow and careful process that I don’t want to get distracted from.

so - end of June for sure (he hopes .. for sure - yeah, something like that! )

I hope you’re enjoying yours!!
barry

[Neil.B]

Looking good Baz. How long do you think it will take you before the cooking starts?

[Baza]

david s thank you so much for such a quick and informative reply! I had read your issue warned to others about the folly of the flame up the flue and I suppose, yes, placing it as a base for the plate does put it in that peril of exposure to flame if they ever got up that high.

A brick and mortar sandwich seems to be the call.

Thanks again!
Barry