36inch build in Redlands

[stevo70]

Re: 36inch build in Redlands

Got another course of bricks up yesterday. Having to taper the tops of them now to avoid larger mortar gaps. Don't know if anyone else has done this but I have been burying pieces of wire into my mortar joins to give me an anchor point for when its time to put the blankets and chicken wire on. Chicken wire especially would be hard to pull in without something to tie it to? Might be an unnecessary waste of time but wont hurt anyhow. Inner arch is going to be ok and I will put a slight taper on the bricks in the centre of the arch for the next course. All going good so far. Also made up a nice stainless base for my flue. Gotta love a nice tig weld. Anybody see an issue with placing this base in the mortar gap between 2 layers of bricks to hold it down or is there a better way to secure it? I was thinking maybe small dynabolts but might split the bricks open?

[stevo70]

Re: 36inch build in Redlands

Thanks Steve. It makes me comfortable with my 1750 x 1500 slab. I think I'll adopt your approach of starting at the back - alow 220mm in case -and then see what I have to work with at the front. Given you were 1600 width, it seems your 900 dia plus 2 lots of 210 is well short of the 1600 width? In my case I'm now tempted to stretch to a 1000mm build (Colin?) because width wise I can make it (2x220 plus 1000). I have a height limit so may have to make the dome circle elliptical if I do that

No worries Tom, Good idea to do what you are doing and get a firm idea which way you are going to go. Also I have cut a slight taper on my arch bricks. Less mortar, much neater. Ask my neighbours what a brick saw sounds like he he he

[Brooky Tom]

Re: 36inch build in Redlands

Thanks Steve. It makes me comfortable with my 1750 x 1500 slab. I think I'll adopt your approach of starting at the back - alow 220mm in case -and then see what I have to work with at the front. Given you were 1600 width, it seems your 900 dia plus 2 lots of 210 is well short of the 1600 width? In my case I'm now tempted to stretch to a 1000mm build (Colin?) because width wise I can make it (2x220 plus 1000). I have a height limit so may have to make the dome circle elliptical if I do that

[stevo70]

Re: 36inch build in Redlands

Hi Steve, just a quik question while I follow your build. What were the dimensions of your slab? I see it's a 900mm oven but I just want to compare the overall with what I'll be doing (hopefully soon). Also are you using rectangular brincks in the arch or tapered ones. Thanks Tom

G'day Tom, The top hearth slab measures 1670mm front to back and 1600mm side to side. I set the inside of the back bricks approximately 210mm in from the back of the slab. That gives me 110mm of brick, 75mm of insulation blanket, and approximately 20mm of render which should finish up the dome close to flush with the back of the slab. I needed as much room at the front for my flue to clear my house roof gutter, which is why I set it right at the back but it looks pretty good and it gives me some bench area at the front. Slab is slightly smaller I think than what the FB instructions suggest but for a 900mm oven, I think its ok. I have ended up a bit higher than where I would have liked. My oven floor is at 1170mm or about 46 inches. I think around 42 would have been better. Perhaps leave out the half besser block in the base next time. Next house, next oven... There will be another, I just know it.

[Brooky Tom]

Re: 36inch build in Redlands

Hi Steve, just a quik question while I follow your build. What were the dimensions of your slab? I see it's a 900mm oven but I just want to compare the overall with what I'll be doing (hopefully soon). Also are you using rectangular brincks in the arch or tapered ones. Thanks Tom

[stevo70]

Re: 36inch build in Redlands

Might be giving myself heartys for nothing. IT tool suggests all is going to be ok. Bit of an optical illusion at the moment I think. Next course of bricks will tell me for sure.

[stevo70]

Re: 36inch build in Redlands

Better still, longer dome bricks for the 5 or 6 bricks that pass over the arch. Make them long enough to sit up on the arch. Probably need to be about 2-3" longer than the other arch bricks. What do you think?

[stevo70]

Re: 36inch build in Redlands

Yes, unless I make my inner arch bricks go back inside the oven further, looks like I am going to miss the top of them. Inner arch is too far forward. Could have sworn I got this right. Might try cutting larger bricks that will sit inside the oven for the top of the inner arch as there is no way I will be able to shift what is already there.

[Wayne73]

Re: 36inch build in Redlands

Your right it wont look weird and you will never be able to tell from the outside, but it will make life easier for you if you get the inner arch right.

[stevo70]

Re: 36inch build in Redlands

Good idea, you'll find you've gone to far with the arch bricks already and you can see that the last three coarse's are not going to marry up with the dome correctly.you can use your indispensable tool to give you an idea how far the arch bricks need to come back.

Yes realised that. Will be blanketed and rendered so shouldn't look too bad and if it looks weird, I'll just mortar the piece back on.

[Wayne73]

Re: 36inch build in Redlands

Will chamfer the top of the inner arch bricks but will wait until Im up that high so I can cut them in the correct place.

Good idea, you'll find you've gone to far with the arch bricks already and you can see that the last three coarse's are not going to marry up with the dome correctly.you can use your indispensable tool to give you an idea how far the arch bricks need to come back.

[stevo70]

Re: 36inch build in Redlands

Thought I would post up some pictures of how things are panning out. I'm pretty happy with how its looking so far, Inner arch is going to be very neat I think. Finished the second chain just now. Will chamfer the top of the inner arch bricks but will wait until Im up that high so I can cut them in the correct place.

[stevo70]

Re: 36inch build in Redlands

Ok you've talked me into it. I'll chop em...

[cobblerdave]

Re: 36inch build in Redlands

Gudday
The strength in the arch is we're the bricks touch on the inside face. The mortar wedge is there to keep the outer pieces apart and orientate the bricks so that gravity can keep the thing locked together. The mortar is a glue in some ways but it also function as a shock resistant spacer as the oven heats and cools expands and contracts.
Same with the dome it's the brick to brick contact to the structure that supplies the strength the mortar at the back just helps to keep the brick in the correct position.
Regards dave

[stevo70]

Re: 36inch build in Redlands

G'day Dave, I probably misled you with my picture in #17. I had just mocked that up with any bricks I could find just so you can get the picture of where I intended to place my inner arch and its contact angle with the dome brick. I have now cut the bricks I will be using and they have a reveal in the bottom to suit the door stop, as do the sides of the arch. As I said before they are only 75mm thick and I don't want to leave the arch too thin but I should be able to run a string line across them and take a small slice off. Yes they will sit neater that way I agree. Maybe the arch will regain its strength once the dome bricks are mortared to it?