Bacterium's 2nd build

[Bacterium]

Re: Bacterium's 2nd build

The teardrop can be a concern.....albeit a "hidden" one. I've been cutting a whole layer of bricks and then I mortar, rather that cut/mortar each couple. My strategy works until you get to that point where you get a join meeting up with one on the below layer. So I'm making it occur up.towards the arch....see how it goes next layer.

My arch bricks towards the top(the back) would be about 40mm inside the adjoining rings. Hopefully to stop the teardrop effect and allowing me to trim both arch and layers where thy meet. I'm hoping this will allow me to cut arch top and rings together. I didn't quite have the confidence where Doug built his arch first.

[ATK406]

Re: Bacterium's 2nd build

Hello Damon,
I like your logic on reclaimed firebrick. These ovens don't generally put the refractory properties of the brick to test (they'll probably never see temperatures in excess of 1200F).

On the subject of your dome/arch transition; In my opinion, this is the most challenging part of the build. The dome build itself is pretty straight forward once you get the hang of it (as you've already seen). The intersection with the arch takes some planning. I would be careful about putting this off too long or you might paint yourself into a corner (or brick youself into a teardropped dome as the case may be). A teardrop dome is not a big deal but the lack of symmetry makes closing out the top of the dome a bit more difficult. Just my .02.

Good Luck,
Regards,
AT

[Bacterium]

Re: Bacterium's 2nd build

Manage to get up to the third layer tonight....Basically I am cutting the brick sides. I sorta guessed it shaving about 5-10%degrees per side for 3 bricks, made some adjustments with my saw guide then cut the rest for that layer. Second course I was a bit off but by the third I got my "eye in" and matching nicely..... gee this is addictive

Arch starts to get out of synch with the layers. I'm thinking of doing layers 3-6 all the way around except 2 bricks wide from the arch. Then cut/fill in up against the arch.

...mmm was going to comment on another thread but thought it might hijack. So the big question is Cut side face points inwards (exposed inside dome) or outwards (covered by dome insulation etc.).

Well I'm using second hand fire bricks which were recovered from a house chimney which was pre 1980's (most likely pre 1970's). Outer edge of the recovered bricks are a bit rough as you would expect for age so the outer face is not soft just rough. This obviously won't give a nice tight fit for the dome inside.

They are a proper fire brick (not just a plain pressed red) as I managed to track down details through some of their markings.
Now I used to be of the opinion that you always put the cut side out believing the outer (fired side) would be harder. Well I was having a look at them (see pics of cuts) with an old brickie mate and he said effectively as long as a brick is baked all the way through the integrity should be the same.

So going over the cuts the cut side is quite tough, occasionally you can spot a flaw (more so a crack) so I don't use that but I'm starting to think in the situation where you are using seconds for fire bricks, why not point the cut face into the fire side of your dome?...........

The other part of my reasoning is as these bricks have a dirty (outer side) that you can see was exposed to the fire inside the chimney, where they originally where.... is that something you want exposed inside your dome (food cooking) . Possibly not if it was a domestic oven, definitely not if it came from a commercial use.

This has been discussed in part before but thought I'd post up my experiences/thoughts to add to the discussion.

[Bacterium]

Re: Bacterium's 2nd build

Colin,
Plan so far was to overlap the 2 arches by about half a brick but have the outer arch with an airgap above inner.....not sure about floor but probably an air gap somehow.

[oasiscdm]

Re: Bacterium's 2nd build

Hello Damon,

Just my 0.02...BTW. I also built my floor with 1'x2' Medium Duty Firebrick Tiles (2.5" thick).AND PHOTOS POSTED

Hi ATK406

Love the symmetry of the base.

Damon how are you looking at constructing the thermal break?
I havent decided yet if i will do so.

[Bacterium]

Re: Bacterium's 2nd build

Cheers guys

Colin I am going to try a thermal break this time so will probably put the outer arch above.

ATK I might play around with measurements for a bit, lower dome has some sense. My last oven was about right for top and bottom cooking evenly

david s I noticed people now talk about a sloped top slab. I went the opposite way and it all drains towards the ash slot. I figure that at least its not flat its got somewhere to go. One the blanket goes on I will fill any side gaps with concrete then render with a slope away (towards the outside, on the outside). So if I seal it good enough my water entry should be minimal anyway......hopefully
To get a flat surface for the calsil I levelled with sand underneath first

[david s]

Re: Bacterium's 2nd build

Hi Damon,
Just picked up on this thread. I was wondering if you mounded your supporting slab up in the middle slightly to prevent any water pooling under the insulation? This is easier to do when making a vermicrete slab because you can then get back to flat on the top of it when you place the stuff. A bit more difficult if using cal sil.

[ATK406]

Re: Bacterium's 2nd build

Hello Damon,
I built a 42" Pompeii last summer. My interior dome height is 22.25" and my entry arch is 19.75" wide by 12.5" tall. If I were to build another oven (as you are already doing), I would make my dome height a little lower (i.e. not a true hemispherical dome).

I would target around 20". I don't know if it would make any difference, but when cooking pizza I am compelled to retain a bigger fire than I really want, to to brown the surface of my pies. Maybe it wouldn't make any difference but I wish I could bring that heat/fire closer to my floor. Everybody loves the pizza, I just wish I could get the top browned a little faster.

Just my 0.02...BTW. I also built my floor with 1'x2' Medium Duty Firebrick Tiles (2.5" thick).

[oasiscdm]

Re: Bacterium's 2nd build

Hi Damon

Nice to see you back. Like you tiles, looking good.
Me i have just been getting my brick saw jig right. Will post some picks of the finished product.

Damn, can't start cutting as I'm going away this weekend, got something on the following weekend. then the weekend over easter wont get a chance to really get much done now until after easter. Can see a couple of RDO's coming on.

Are you looking at thermal breaks at all or are going to run tiles out into the vent?

[Bacterium]

Re: Bacterium's 2nd build

I'm still here and just I got cracking again.... (ooopppss no pun intended for those with fresh build cracks)

Earlier last week I got my floor insulation cut and down - 75mm (3in) thick of CalSil

Weather was a bit hot Saturday but it it was out with the brick saw and wrestled the 6 fire brick floor tiles (600mm x 300mm each) through it. Managed to get some level of curve with numerous cuts. The front two will get trimmed up once arch template is ready.
Basically my oven floor is inside, so the first course (on outside) sits directly on the CalSil. I played around with the saw cutting guide thingy and shaved off about 5degrees each side.....laid them up and gaps were minimal....gee this is getting addictive
.......then it all got to much and I just "fell" into the pool.........ahhh


So effectively I cut the first 2 courses and dry laid them - picture is just part way through the first one.

I've got some ply down on the inside (top of floor) and just working out my IT/dome gauge.

Think I will also build my inner arch template with some ply. The idea is to dry lay them (only side cuts, not front/back cuts). Then as I do each course and as I get around to each arch "course" I can then do the front/back cut (of the corresponding arch brick).

I'm working on a 600mm (23in) wide inner arch
my oven floor internal diameter is 1150mm (45in)
or 575mm (22in) radius
so aiming for 63%
that would mean an inner arch height of 362mm (14in)

clear as mud!!!! if not please let me know if I'm not on the money

so once I have all the templates/gauges sorted, I'm hoping to get my high heat mortar out and be cracking!!! on the weekend.....obviously I will leave a few cuts out until the day for any "adjustments".....

[oasiscdm]

Re: Bacterium's 2nd build

Hi damon


Actually just had a shop bought pizza. Yuk!!! dont know why i bothered could have sat here and dreamed about making one in my wfo now all completed, fired and cooking it. Yum feel full already.

I can only dream reality a few months away.

[Bacterium]

Re: Bacterium's 2nd build

Lol so true Dave.

Time for wood fired oven proverb........I'm enjoying a glass of red....
Many people talk about em , mates build cheap ones, whereas friends actually build em.

No worries Colin, Frank from Avero is the go. He had a range of thickness and shape varies between 300mm x 300mm or 600 x 300.

Ahhh wish I had a wfo pizza right now.

[cobblerdave]

Re: Bacterium's 2nd build

Gudday Damon
Sounds like you have been busy. Good thing about a WFO , the pool would go green if left alone, grass would grow up betwwen you pavers,even the kids would go feral if left alone.....but the oven will just sit and wait for you.

regards dave

[oasiscdm]

Re: Bacterium's 2nd build

Hi damon

I am curious where you sourced them [tiles for floor] from, just for future reference and to help others that might want to do a floor with minimal seams.

Especially since i now know where to go for cheaper freight.

[Bacterium]

Re: Bacterium's 2nd build

Colin,
This time around I was going to do it in standard size fire brick but the seconds I have are only really good enough for dome cuts due to busted/rounded corners. So rather than just buying brand new fire bricks why not just buy them bigger. Think I could even fit them in my bricksaw to.do corner cuts