42" In South GA

[UtahBeehiver]

See it this helps.

[edonovan]

I think the more I read I am complicating it more in my head or something......I read over several builds, looked over UtahBeehiver tips on the arch and tying in the dome (and reading that this is the most difficult part for builders to visualize.), go back outside look...stare...hold up bricks...cut scrap bricks...and something still isn't working correctly for me. I am hoping that my arch placement isn't too far in the dome. First picture is a side shot and you may be just able to make out a pencil mark inside the arch form...that is my ID...If I place a tape underneath my arch dome that mark is right at about 2" from my heat break/ front of arch (23" from center). The next picture is what I have been coming up with, although obviously if I were to hold up my brick in my IT it would not sit correctly on my arch TDC, also I keep questioning if that is where the dome brick is supposed to intersect the arch or is it lower on the arch brick. I have tried marking the OD on the top of the brick, the problem comes in when I try to mark ID...the ID mark is still on top of the TDC (when working with a full brick) and that just throws me all off. So walking away from it today, I cut some more bricks in half for more dome bricks when the time comes...if this arch doesn't beat me.

[MarkJerling]

Don't overthink it. The way you have it in your second photo looks fine!

[mongota]

I agree with Mark, I think your second photo looks just fine.

If Russell's photo, which is terrific, didn't help? This may not, as it's pretty much the same thing...but this link sort of shows the arch brick in place on the arch. It may help the visualization a bit. My layout to achieve the cut lines on the arch bricks is just slightly different than Russell's for one of the cut references. I simply used where the bottom edge of the brick met the inside face of the arch template as the third reference point on the bottom of my arch brick instead of using the ID of the dome on the bottom edge of the brick.

Set your brick in place upon the template. Draw a line along the side face of the arch brick that follows the line from the orange to yellow dots. That would be along the red line in my photo. Then draw another line on the side of the brick that follows the inside diameter of your dome. I used the inside dome diameter (the yellow dot) as one referecne point but then used where the brick sits on the arch template (blue dot) as the other reference point fo that second cut. Simply my choice.

Here's the link to the pic, there's a bit more text on my post explaining the dots and cut lines. https://community.fornobravo.com/for...414#post392414

[JRPizza]

If the arch is located properly, meaning it will intersect the dome without going out of round, there are a few inches of forward/aft location you can play around with. Forward more and you will have more arch protruding from the dome and less to cut off the TDC brick. Aft more and the opposite happens. My arch is not all the way forward but I have a pretty good amount sticking out. The pics below shows how much I cut off, which is similar to what Russell showed. Your's looks in the ball park to me. In my second pic you can better see where I have drawn an arc representing the ID. The angle you cut on the upper surface should be steep enough so you have room for some mortar.

[edonovan]

If no one has told you guys lately....YOU ARE AWESOME!! Thank you UtahBeehiver, MarkJerling, JRPizza, mongota !! It was definitely good for me to walk away from it last week, and come at it with a new set of eyes. Between knowing that this is the most difficult part for builders to visualize and mark telling me to not over think it, really helped me think this easier than I am making it. Well, reading through Mongo's "string method" was easier to visualize without having to try hold a brick in my IT and mark bricks and everything...it just starting clicking!! Have company this weekend and the big FL/GA game...so probably not too much happening this weekend...but I do feel SOOO much better about moving forward and progressing along less stressed!! Thank you again everyone!!

[edonovan]

Again...Awesome!! Thanks again everyone!! Minimal frustrations with this, maybe some cuts that provide some challenges when matching up with dome bricks... but nothing I can't live with... Great feeling to have this hurdle done!

[Giovanni Rossi]

edonovan, I've enjoyed following your build. It must feel great to have completed this critical step. I want to echo everything you've written about the primary contributors’ value to this forum. I also want to highlight one tip for those of us still in the planning stage that I haven’t seen before and I’m sure I would overlook in an attempt to make accurate cuts.

From JRPizza: “The angle you cut on the upper surface should be steep enough so you have room for some mortar.” I’m sure this detail is second nature to those well versed in this type of construction, but not for me.

All the best as you finish your dome. Giovanni

[mongota]

edonovan

Again...Awesome!! Thanks again everyone!! Minimal frustrations with this, maybe some cuts that provide some challenges when matching up with dome bricks... but nothing I can't live with... Great feeling to have this hurdle done!

I remember fou sort of "semi-great moments in building history" when I built my dome.
1) Getting the first course of brick set. "It has a shape!!"
2) Figuring out and finishing the arch. "In the end, much ado about nothing". I thought so much about HOW to do it in my head. But once I held the bricks up where they were supposed to go and saw the geometry they were supposed to take, it was all so very straightforward.
3) Covering the arch. "Dang. Now that looks like something." So much done, and although the dome plug seems to be within reach, at the same time the plug seems so very very far away.
4) Plugging the dome. "DUN". Time for a beer. Now on to the tunnel!

When you cover the arch, I found it easiest to have the brick-to-be-cut in the IT, held next to its intended position. Scribe an inside and outside cut line on the brick, connect the lines, and cut. Put the brick in the IT and test fit. Repeat as needed. They don't need to be amazing cuts. Mortar will fill the gap. But you don't want so much mortar that the brick slumps, nor do you want so little that you have brick touching brick and you can't tap the brick fully in to its intended position.

To prevent arch droop, it might help to use a half- or third-brick (depending on how high you are in the build) and cut that to fit against the arch. Then work away from the arch, infilling between that cut arch brick and the other bricks already in that course. I've noticed droop in builds where guys try to use a brick an inch or two longer than those half- or third-bricks already in the course. They try to reach the arch with one long brick versus a half- or third-brick plus a small infill. Or droop can occur when you use small infill pieces. If infilling, watch the height of the IT above the oven floor. Keep it consistent so the small infill pieces don't get set low. Low = droop.

Sorry to ramble!
Good work, the plug is close. But no too close! lol

[Baza]

You are moving along amazing!!! WELL DONE!!!
I completely sympathize with you on the perseverating (analysis paralysis!) but you did the right thing and reached out in this forum to some amazing people!!
I know I couldn't have done anything without their sage advice!

The droop is a real thing - and I was lucky to avoid it using the lens Mongo shared - and remember - the cuts you make to meet the arch will NEVER be seen (except in this forum where there is an abundance of both forgiveness and understanding! ). So, if you have to tie in some 1/2 or 1/3 bricks and they are incongruous to the rest of that course - don't worry - only you will know!

Keep the pics coming!!
Barry

[edonovan]

Whoa...well holidays are here and work has been....moving....kind of slowly...but moving none-the-less. Thank you everyone again for all the words of encouragement, tips and tricks. Feeling SO much better about getting past that hurdle. A couple questions...
1) I have been planning on a 20" high dome (42" diameter oven) and was wondering when I start creeping my IT back? Is is once I clear the arch, just start pushing it back each layer?
2) As the layers start to not take a lot of full 1/2 bricks, do most just start cutting the 1/2 brick in half? (the 4.5" lengthwise) ....this is what has been working for me to correct some joints lining up...still couldn't totally avoid it, but making corrections as needed as best I can.

[NCMan]

Lookin' good!!

[mongota]

To transition from a 21" radius to a 20" dome height, I would have been reducing the IT much earlier in the build, well prior to covering the arch. You can gauge how many more courses you have and divide the height you need to lose by the courses remaining and then reduce the IT by that much per course. But if you need to lose 1" over your remaining (for example) six courses that might be a bit much with regards to the course-to-course transition. The top of your dome might actually flatten out a bit too much. You could hold a flexible batten over the top of your dome to see how it looks visually. It can still work for sure. But you'll likely have to manipulate/rotate the bricks as you set them to avoid significant stair-stepping or lippage between courses.

The thing is...it can ALL work. You just make it happen as best as you can.

As far as transitioning to smaller bricks, I went from half-brick to third-bricks. I might have transiitoned from third-brick to quarter-bricks in the course right before setting the plug.

As a complete aside...I got a message from someone maybe a year or two ago who felt their perfect 21" dome radius was too high at the apex. He was going to tear it apart and rebuild to lower the height by an inch. I offered the idea of pulling the floor brick and "raising the floor" with an inch layer of ceramic fiber board insulation. Then resetting the floor brick on top of that. Obviously his floor brick was cut to fit inside the dome. The only caution I offered was with regards to oven access through the arch, was that his arch access would be reduced by an inch in height. He did that modification and in his feedback he said the reduced arch height opening was not an issue with regards to oven access.

[MarkJerling]

As a complete aside...I got a message from someone maybe a year or two ago who felt their perfect 21" dome radius was too high at the apex. He was going to tear it apart and rebuild to lower the height by an inch.

I can't see that one inch would make any difference to the practical use of the oven, heat retention, etc. And it would be hardly visible.

[UtahBeehiver]

Is there a particular reason you are lowering the dome height from 21" to 20", it really does not make it a low dome oven and it means a lot if extra work. I agree with Mark that the 1" will not make any difference visually or operationally all said and done.