cobblerdaves build

[cobblerdave]

Re: cobblerdaves build

G'day
Using an iPhone 1 pic per post



Pic of the back of the external door. It has an alumimium rim which fits into the entrance and stops anything that blows around it. The bottom is a piece of hardwood attached at a slight angle. Thus the weight of the hardwood plus a firebrick effectively keeps the door up against the brick without the need for hindges or catches to be drilled into the brickwork.
This is still mk 1 and works well enough and is not to ugly so I havnt changed it.
The black mark on the face of the door in the previous post is flying fox poo. They're a large fruit eating bat, so the poos highly acidic. It will strip the paint off you car if you leave it same with the dome paint. So the domes got the added advantage off being flying fox poo proof.
Regards dave

[cobblerdave]

Re: cobblerdaves build

G'day
The rendered dome was never a problem with water. I did have a crack at the junction of the back of the brick chimney and the render. Wheather kids climbing over the dome or just plain diference in temp I dont know. I chased out the crack, filled it with paintable silastic and it was never a problem from then on.
The chimney and entrance structure is all supported on a single skin wall of brick and I seen the sense in buttressing it. The skin of brick was an extension of this and I like the look. The added advantage is that the house brick are water resistant and I don't have to paint the dome render from time to time as I had been doing.
The single " problem" regarding water has always been the entrance and rain getting on the firebrick entrance floor and wicking it's way back into the oven itself. I extended the entrance at first and finally have an external plug style door. Rain doesn't fall gently strait down around here. It's usually a storm with winds that push 2 inchs of rain in an hour all sideways.

Regards dave

[gastagg]

Re: cobblerdaves build

Dave, why did you decide to put a brick veneer over your stucco finish? Were you having water problems? I'm planning a dome (for visual reasons) and am planning stucco finish on a slab top similar to yours. Any problems with leaving it that way?

[wotavidone]

Re: cobblerdaves build

Thanks Dave,
Looks like the lifespan of Hebel is not an issue.
I still will try to apply your advice, though.
Just took a photo of my hearth bricks, which are of course pressed clay pavers with rounded edges.
They seem to beholding up OK.
The arch bricks are wire cuts, Littlehamptons. I have managed to chip a couple with the peel.

[oasiscdm]

Re: cobblerdaves build

Nice to hear Dave.

Its good I can check the front [underneath] of my floor forward of centre to check for of the oven. I have noticed with my temporary door calsil then hebel free standing, that the back of the calsil gets mighty hot but with 75mm hearth tiles should not be a problem. Guessing the Hebel will last forever.

My next build I will have front and rear access to the oven base to store wood, but would not change a thing from this build.

The Hebel stands up well and I will say is much easier to work with than pouring a concrete slab.

however my temp door although still in tack is starting to show the effect of intense heat, even with calsil in front of it.

Oh and Dave I am getting closer to the TDC decorative arch Finish and some more diamond die grind etching but more complex than the Yin and Yan symbol inside the oven as we have previously discussed.

[cobblerdave]

Re: cobblerdaves build

G'day
Regarding using powerpanel hebel as an alternative to a poured slab the following builds are a good read. Both members are current and I'm sure would certainly answer a question.

http://www.fornobravo.com/forum/f51/...tml#post136921

http://www.fornobravo.com/forum/f51/...tml#post162492

Regards Dave

[cobblerdave]

Re: cobblerdaves build

G'day Mick
http://www.fornobravo.com/forum/f43/...html#post88624
This was my inspiration oven when I first started with a stack of house bricks and some dreams. It used hebel for the base insulation and having a readily borrowed supply of these it was my choice of insulation.
I took a good look at the oven today to see if I could find any evidence that the oven was sinking into that hebel insulation. I'm happy its now 4 years and still alright! Can I say that in another4 years time, that I don't know!





Sorry the oven was last used with a Tuscan grill and the walls are as black as.
But after a good investigation I didn't find any evidence of the dome subsiding as you could expect considering the dome is built outside the hearth floor not on it.
The hearth floor is still straight an level. I used two different size levels to get as much of an idea of how level the floor was and it was good. I did find two bricks that were slightly raised in two different areas. But that was probably my own floor levelling to blame there. I really checked the edges as I usually pushed the fire and coals to either side when cooking pizza. You could expect these areas to be effected most, but nothing.



I did find a lot of chipped edges on the hearth bricks very evident at the entrance. But I'm noting that a lot of dishes and pans and the Tuscan grill gets dragged over it so I'm excepting this a general wear and tear. I also use the entrance as a fireplace as well so a few larger logs do get thrown on there. The oven still operates well and you certainly don't notice them unless you look. So I'm excepting this a general wear and tear. Definitely will no bother to replace any hearth bricks.
Id like to know,Mick if your hearth with the round edge pavers has any chips like these?
So at this stage its still standing up alright, but my position is that your better to add a layer of insulation to protect the hebel from the worst heat, and treat it as secondary insulation.
If you using powerpanel as a stand hearth slab alternative its particularly important as the hebel has a steel mesh imbedded in it. The steel will attract heat expand and lead to cracking of that slab layer.... that would not be good at all!
Regards Dave

[wotavidone]

Re: cobblerdaves build

Dave,
It's been a while since I asked for an update - how's your hebel underfloor insulation going? Still no evidence of breakdown?

The oven I helped my mate build in January has had a serious flogging. Still no decent chimney, I knew that'd never get finished once he started cooking.
(As project managers go, he's a bloody good cook. )
The floor has held up so far.

I'm asking because another mate wants me to help him build an oven in a couple of weeks time, and he's been talking to mate number one - so he wants hebel under the floor too.

Regards,
Mick

P.S. Whaddya reckon if I humour him on the three inches of Hebel he wants to use, then persuade him that a couple inches of perlcrete on top would be good?

[brickie in oz]

Re: cobblerdaves build

Can I suggest checking out a build in the "getting started" section, page 2 called "Budget build 36" ". Pages 12 and 13 you'll find pics of the completed dome sides and roof.

If you click on the #whatevernumber in the right hand corner of a post it will take you directly to that post, Copy paste then no one has to search for it...

Example, this is post #76

[Lancer]

Re: cobblerdaves build

Great advice guys! That is perfect dome cobblerdave, and now I know its a source of strength as well. It amazes me the knowledge you guys have accumulated. Thanks for sharing.

[UtahBeehiver]

Re: cobblerdaves build

Lance,

I was one obsessed with having tight joints throughout the whole brick. I spent countless hours at the wet saw to accomplish. In the end, if I were to build another build, my focus would to have tight brick joints on the interior of the oven "only" and not worry so much about the gaps on the outer portion of the dome (mortar is your friend). Still and advocate of tight inner joints though.

[cobblerdave]

Re: cobblerdaves build

Gudday Lancer
I can see the sea breezes bowing the dust away from your face and the internals of its motor but you might want the check out Bathurst build 100 ish in the Aust section for some niffy mods to a drop saw.
On the subject of mortar, as you build the oven the mortar acts as the glue to hold the pieces in place. Once that last brick goes in the role of the mortar changes. Its now a dome and owes its strength to its shape ( and Gravity) rather than the strength of the mortar. The mortars role is now one of a cushioning between the brick parts and the orientation of the bricks rather than the primary glue. In the home brew mix the Portland cement will be burnt out by the heat and at the same time the lime will be set by the heat and be the final "glue" in the mix. "Glue in the sense that it keeps the sand together in the mortar and the mortar stuck to the brick, rather than being the strength of the dome.
Can I suggest checking out a build in the "getting started" section, page 2 called "Budget build 36" ". Pages 12 and 13 you'll find pics of the completed dome sides and roof. This build has minimal cuts in its construction and larger mortar gapes than your probably used to seeing. Its a dome so, its strong as a fancy cut one is and I'm sure it will be used for many years to come. Particularly note the date from start to pizza you'll be amazed on how quickly it was constructed.
hope something here helps
Regards Dave

[Lancer]

Re: cobblerdaves build

I used a wet saw once for tile, likely a different thing. Have a 10" chop saw and Sho made a test cut a couple weeks back down by the ocean. He said no problem with the dust but normally the breeze is blowing pretty good out there.

Great dome shape, that's so appealing. I've read that only the brick should be exposed to the direct flame and not the mortar. In other words that the bricks should meet on the inside and be raised a bit in the back which is where the refractory mortar goes. Is that what you did cobblerdave? Is it even accurate?

[cobblerdave]

Re: cobblerdaves build

Gudday

Better?
I borrowed a 12 in chop saw with a masonsry blade fitted, but the dust was truly scary. I prefer not to wear a mask, why not enjoy the day! The chop saw was mainly used to cut small slithers for over the oven entrance.
The rest is brick cut in 1/2s with a brick bulster then those 1/2s cut again giving you 1/4s . The face you see is 1/2 a brick on the long side 1/2 as thick.
To the top of the oven this were again cut cut down in 1/8s
Regards dave
Ps check out gulfs build he has cut his brick into " tiles" with a wet saw a lot more consistent thickness.

[Lancer]

Re: cobblerdaves build

Gudday
[ATTACH]35756[/ATTACH]
A bit more progress I'm getting to like the effect more and more. I'm getting to the top of the dome now and the tighter circle has me using alternate 1/2 and 1/4s . Going to have to start cutting some angles on the brick though those gapes are getting bigger. Was a bit worried that the vent plug would not end up in the middle but whichever luck or good management it seem to be true enough. I cannot remember how I actually centred it when I fitted it.
Well back to the tools ..... You can't beat a Brisbane autumn day
Regards dave

cobblerdave, 1/2 and 1/4th what? Brick? Yet they look about the same...