OctoForno

[GianniFocaccia]

Re: OctoForno

Chris,
No, I haven't been to IMS, but it's nice to know they're there. I got my steel from Starow Steel which is about five miles from home.

[Dino_Pizza]

Re: OctoForno

John, glad to hear you got your job. But working just 90 minutes a day is tough. The weather is quite nice so set up some lights and keep going!

You're doing all the things I now wish I've done on my oven. The fire break on the hearth/floor is great and the soapstone floor is way cool. I've seen others do a small air gap with insulation on the inner arch walls where they touch the dome and I'm sure you've been thinking and planning on something too.

You're off to a great start,
-Dino

[GianniFocaccia]

Re: OctoForno

Well, with the new job, I've managed to complete a few weekends of work on the oven in between the rain and the kids sports, enough to report on.

I was not successful getting my soldiers to bond in last fall's 100F heat so I decided to cut the angles off and install the remaining 5" deep brick as a horizontal first course. My second course was 4.75" and the remainder are all at 4.5". The wishful thinking here was that per the Auroville Institute on Vaulted Structures, a slightly deeper pier might positively alter the line of thrust.

The next few courses went in easily and I found I could bevel each brick without a jig. I've been pretty satisfied just beveling each ascending course just using my eye. Then something interesting occurred where I had precut the entire 6th course saturday afternoon and left them to mortar in the morning. I'm not sure if gravity pulled the bricks down in one shot or if they slowly migrated into the position you see in the pic below.

John

[GianniFocaccia]

Re: OctoForno

Here's some more pics of construction of the inner arch, my SketchUp profile, and the dome template I used. I'm really pleased with the way the transition turned out.

[GianniFocaccia]

Re: OctoForno

Some more transition pics

[dmun]

Re: OctoForno

That's an extremely well thought-out and executed transition. Great!

[Paul in Rockwall TX]

Re: OctoForno

John, you and Doug have put on a tutorial of how it's done. If I ever do another (doubtful, unless a friend ropes me in), I'd know what standard to shoot for.

[GianniFocaccia]

Re: OctoForno

Thanks for the kind words, gents. So far, this build has been nothing but a labor of love and a tribute to all those who have built before me and shared (and bared) their handiwork.
John

[ThermoJax]

Re: OctoForno

Wow !!! You and I started at the same time, and I rushed my oven. Your is perfection. Super job. Keep going. I can't wait to see the finished oven. I know you will love it. Congrats.

[SCChris]

Re: OctoForno

The oven is looking good and I love the look of the SStone floor!! The next ring is over the arch and you have all of the skills wired, so things are going to move fast now..

Again, Looking very very good!

Chris

[Mike D]

Re: OctoForno

John,

Are you trying to make us all look bad (ok maybe just me)? That is one nice looking build, I wish I could put it together like that. Keep it going.

Mike D

[GianniFocaccia]

Re: OctoForno

Tom,

Thanks. Yeah, we may have started at the same time but you've been cooking in your oven for months now. Some days I can 'smell the pizza' coming out of my oven but most days all my oven provides is testamony that I am the world's slowest mason ever.

John

[GianniFocaccia]

Re: OctoForno

Thanks Chris and Mike,

I can thank you, Chris, for getting me on the SStone thing. Hopefully, I'm gonna have a lot of data to report back on re: floor vs dome heat-up times, 4" floor thickness and heat retention, and using the SStone as an 'element' to cook casseroles, simmer soups and beans, etc. Although I have (so far) elected not to install thermocouples, I'm hoping the IR thermometer will initially teach me enough about heat management so I can later just cook by the seat of my pants.

Mike, to be honest, I was so apprehensive about taking on this project (I'd never really built anything previously) that prior to starting I analyzed it to death. Thank heaven for SketchUp!
John

[ggoose]

Re: OctoForno

John,

Great looking build
I am curious as to how you cut the tapers in your arch so precisely? Did you use a 14" block saw, or a 10" tile saw and flip the brick a few times? I'm having a bit of trouble cutting those tapers using my 10" saw. Seems I have to approach the cut from about 4 different positions and it is difficult to realign the blade with the cut (proper taper angle) each time. Any hints, 'cause your cuts look just about perfect!

gene

[GianniFocaccia]

Re: OctoForno

Hi Gene,

Thanks, I'm happy with how the arch and transition came out. Here's the process I used:

I used my 10" HF saw with a continuous rim HD Husky tile blade. Once I had settled on the shape of my arch (slightly flattened hemisphere) I drew out the arch on a piece of cardboard and came up with the taper dimensions for 21 bricks. Since my arch is not a true hemisphere (slightly flattened) each of the tapered bricks is slightly different, but not enough to notice. I then made a template out of piece of firebrick (pic 1) and used this throughout the arch.

The photos in my build thread show the slightly triangle shape 'core' that my arch bricks started from and pic 2 shows the outline I used to cut my bricks. The masonry pencils used to draw the outlines came courtesy of Tom (tscarborough), BTW. Once I had the outline drawn I held the brick up (off the saw table) against the saw blade. I made a shallow cut (1/2" deep) following the guide lines all around and repeated this until the blade cut all the way through. Any high spots left on the side of the brick I then leveled with my angle grinder.

The next step was to make concave (radius?) the faces of the brick that point into the oven and down towards the floor. I did this by slowly dragging the face to be contoured perpendicular against the blade. Not 90*, but slightly less (eyeball) so I ended up with a very shallow crater. I did this both vertically and horizontally across the small face that you see from the inside of the oven. The brick in pic 3 shows how I'm doing the same thing by contouring the face as well as the tops and bottoms of the dome bricks.

Yeah, this takes a little more time but I only get to build this thing once.

One other thing. I didn't initially build the entire arch before moving on. Like Karangi Dude I felt it beneficial to match each arch brick to the corresponding course it touches so that they both lined up correctly. Only at the very end did I complete the arch before building the course that laid on top of it. The trick I'd like to share is that I tapered all of the arch bricks and stood them in place using soapstone shims to simulate their proper spacing. I then used an indispensable tool with a pencil to trace the proper interior horizontal dimension before cutting. This is how I got them to line up with each other (post #34 in my build thread) in an arc consistent with the interior dimensions of the rest of the dome. Also, don't be afraid to use the side of the blade to do the super-fine custom-fitting. This is really useful when cutting the parallel bevels that face the interior of the dome.

I'm wondering if any of this makes sense. Since I've done it, it seems rather straightforward, but if you have questions I don't mind answering them. I feel this type of arch is arguably stronger than straight-sided arches and it's aesthetics make it worth the time it takes to build it. It's also been the most fun part of my build by far.


Hope this helps,

John