My Build 42" oven GT

[gtofani]

Re: My Build 42" oven GT

I finished the 8th chain this evening, I noticed the water from the hose feels warmer than the water sitting in the bucket, winter is coming. I hope to get the dome and chimney done before its too cold. I used sticks on this chain then after placing a keystone in the chain, removed sections of the sticks to wash the inside. I replaced them until the mortar sets. Its a little more work but I like the clean joints on the inside, I am going to do as many more chains as I can this way.

[IMG][/IMG]

[benguilford]

Re: My Build 42" oven GT

Looking very neat there, I see you've been cleaning your brickwork as you go. Sound plan! I failed to do that, and subsequently spent several hours scraping the mortar off with a chisel and scourer. The home-brew mix sets hard as a rock!

BTW, nice lake you have there. I aspire to have a lake just like it, is it stocked with trout?

[gtofani]

Re: My Build 42" oven GT

An inside shot after the 7th chain.[IMG][/IMG]

[gtofani]

Re: My Build 42" oven GT

thanks, Got another chain done tonight, row 7. I had to stick a few and use a combination of regular halves and tapered bricks to make it work.
I am happy with the results. I think I am done with the indispensible tool for placing the brick. Chain 8 will need to have the styrofoam form in place.[IMG][/IMG]

[benguilford]

Re: My Build 42" oven GT

Looking brilliant gtofani! Well done!

[gtofani]

Re: My Build 42" oven GT

I got row six done this afternoon, cool enough for a sweatshirt, not too hot to sweat and sunny, nice weather to work on the oven.
No problems with the rows sliding yet, I am now past the arch with a wedge cut out about half way through the brick over the arch to finish the row. I made the last two pieces like a keystone, they fit nicely with under a 1/4 inch of mortar.
I will try row 7 to see if I have trouble with the brick sliding, It also looks as though I should cut a taper on each brick to avoid the large joint on the outside. I am thrilled so far with the dome.[IMG][/IMG]

[Laku]

Re: My Build 42" oven GT

Also the brick width will get gradually smaller as the circle gets tighter. At least if you want to keep them staggered or don't want to have huge seams beneath the bricks.

ps. I cut all my bricks with angle grinder, not too hard specially if you have tile saw.

[gtofani]

Re: My Build 42" oven GT

I may try to cut the brick on the 7th chain so each is tapered on the sides.
There shouldnt be too many and the wet saw makes quick work of it. Or even every other brick could be tapered. I'll decide after I see how the 6th chain goes. I figure the chains circles get smaller as you get towards the top and that makes the larger outside gaps that have to be to fill with the mortar so tapered brick will help reduce that problem.

[Laku]

Re: My Build 42" oven GT

I used high heat mortar from a Finnish brand and when the gap got too big for it, I used a mix that their in-house fireplace mason instructed to use. Would probably use home brew now if I did it all over again, but that's another story.

My bricks were tapered only between each brick of the chain, as I think it's the only seam that really affects how strong each chain will be as self standing structure (I could be wrong). Also allowed me to use the high heat mortar for the complete seam.

[benguilford]

Re: My Build 42" oven GT

What mortar mix did you use Laku? I used the home-brew mix listed here on the forum, mixed up to a trowellable consistency, but I found I had to wait 3-5 minutes for each brick to set enough to hold once I got to the 7th of 8th chain.

Actually, I think I have found my answer as I look at your photos - it looks like you cut all of your bricks to be tapered on all faces, such that you don't have any large mortar gaps on the outside face. That must have taken you ages!! Looks fantastic BTW. This would make a huge difference when laying the bricks, as the thin section of mortar would 'set up' almost immediately and hold, even on such a steep surface.

For myself and gtofani I don't think that method would work, as we both have/had a significant mortar gap between each adjacent brick in the chain, and between each chain on the outside face of the dome. This means there's just too much wet mortar in each joint, so when you start getting to the steep chains it takes ages for it to set and hold.

Has anybody else found this? I keep seeing people managing to build all the way to the top without using the form, and wondering how on earth they managed to do that! Would my reasoning above explain this?

[gtofani]

Re: My Build 42" oven GT

Thanks for the photos of the form for the top chains.
I just completed row 5, row 6 appears to be the last one where I have to make cuts at the arch.
I am watching the joints more closely, inserting a sliced brick once in a while to stagger the joints,looks much nicer.

[IMG][/IMG]

[Laku]

Re: My Build 42" oven GT

When it starts to get difficult you can use sticks to keep up the first few. Once you got like 3-4 that have dried for something like 3-5 minutes you can start building as usual. As long as the 1st brick you put on that chain is supported from beneath. (see the image below)




I think it got harder for me around 9th or 10th chain.

[benguilford]

Re: My Build 42" oven GT

I have a feeling it'll be different for a 42" oven, but for my 36 inch I started to have difficulty around the 8th chain. I could have kept going with the tool, but I had to wait too long for the mortar to start to set prior to moving to the next brick (and I am an impatient individual). I made a basic polystyrene form and propped it up internally with bricks;

[gtofani]

Re: My Build 42" oven GT

how many chains can I go up before the bricks will start sliding down?
Does anyone advise a form at that point?

[gtofani]

Re: My Build 42" oven GT

ok, thanks I got it now.

[IMG][/IMG]