Out of work Pizza Man's 42" Build in NJ

[deejayoh]

Re: Out of work Pizza Man's 42" Build in NJ

Five degrees may or may not matter in your build, depending on how tight you want the joints. Being off five degrees at the start could carry through your whole dome.

I see that you are using an IT which will help to control that - but I am not sure about your IT design. The axis of your IT should hit right at the middle of the brick in each course. Your IT design hits at the top of the brick. That will result in each course being slightly steeper than it should be, will eventually affect your dome.

See this thread for a better explanation
http://www.fornobravo.com/forum/f8/t...ice-17817.html

[spiderrinaldi]

Re: Out of work Pizza Man's 42" Build in NJ

The axis of your IT should hit right at the middle of the brick in each course. Your IT design hits at the top of the brick. That will result in each course being slightly steeper than it should be, will eventually affect your dome.

I don't think you can see it well in the pics but the IT does touch the bricks in the center of the bricks, like in pic #3. With that said, I do agree that my IT is less than optimal. I will have to scavenge a few parts around and make a better one.

[Tonyp]

Re: Out of work Pizza Man's 42" Build in NJ

I don't think you can see it well in the pics but the IT does touch the bricks in the center of the bricks, like in pic #3. With that said, I do agree that my IT is less than optimal. I will have to scavenge a few parts around and make a better one.

Do you mean the top edge of the wood being at the center point of the vertical soldier? It doesn't matter with the soldier course since they are vertical and simply a set distance from the center point of the oven. When you start the next angled course though, the center of the brick should be in line with the pivot point on the IT. The way your IT is set up currently this line is actually the bottom edge of the wood.

You could make your current IT work with a little modification. Simply cut your wood down to half the thickness of your brick. The top edge of the wood piece would then be inline with the top edge of your brick and the bottom edge in line with the brick center point. You could even extend a piece of metal outward on the top face of this wood piece to give you a L shaped bracket.

[spiderrinaldi]

Re: Out of work Pizza Man's 42" Build in NJ

Do you mean the top edge of the wood being at the center point of the vertical soldier? It doesn't matter with the soldier course since they are vertical and simply a set distance from the center point of the oven. When you start the next angled course though, the center of the brick should be in line with the pivot point on the IT. The way your IT is set up currently this line is actually the bottom edge of the wood.

You could make your current IT work with a little modification. Simply cut your wood down to half the thickness of your brick. The top edge of the wood piece would then be inline with the top edge of your brick and the bottom edge in line with the brick center point. You could even extend a piece of metal outward on the top face of this wood piece to give you a L shaped bracket.

OK, I understand what you mean. Yes, I see now where this could be a problem moving forward.

Just picked up another 100 Firebrick. Going to hopefully get a lot of work done today through this weekend. Hope the weather in NJ stays as nice as it's been.

[GianniFocaccia]

Re: Out of work Pizza Man's 42" Build in NJ

Gonna offer the same as I got from a guy I was paired with after a (usual) succession of inaccurate tee shots I made on a course I played for the first time:

1. Did not attach board to hearth slab

- You'll be fine. (No need to do this)

2. I did not use the sand/fireclay paste underneath the hearth floor

- You'll be fine. As long as you're level you're good to go. Any moisture collected will dry during curing.

3. After I cut them I realized that I made a mistake and they were actually at 25 degrees

- You'll be fine. As your build progresses you will undoubtedly reduce the number and severity of items you feel the need to do over. Since it's your name is on the finished oven, its your call how pedantic you want to get with it. I went off the charts with mine.

Remember, this is your build and all ovens are unique. The slight imperfections are what gives each of our ovens character.

John

[spiderrinaldi]

Re: Out of work Pizza Man's 42" Build in NJ

Today I finished the next course. I will get a picture up at a later time. I did not taper this course at all, and I didn't like how wide the mortar gaps are on the outside part of the oven. I have decided to begin tapering the remaining courses. I cut a bunch for the next course and tested my cuts by dry stacking them. They line up really good. Did a 5 degree cut on both sides of the half brick to taper.

I also fixed my IT.

What am I supposed to do with those left over chips? I see some people using them as some sort of spacer in their builds. Are they there to simply fill in voids, and are later cut off with an angle grinder? Can someone explain?

[kbartman]

Re: Out of work Pizza Man's 42" Build in NJ

OK, I understand what you mean. Yes, I see now where this could be a problem moving forward.

Spider,
Nice start on your oven. Looking good. Best of luck with your build.

Since the subject on the IT is back in the spot light. I would like to put my 2cents in again. I'm no math or geometry wizard but did played a lot with my "IT" during construction. As seen with the attached pics, I believe the bottom of the brick is the were IT rod needs to connect to brick bracket. I finished my dome with the rod attached to the bottom of brick bracket with full success and no offset of courses. It seems to me and also proved out as seen in the pics that a small offset would still be introduced with the bracket in the middle of brick. It maybe not perceived or as much as the top of brick, But still may exists. I posted a similar observation during the construction of my dome and no one commented. I'm still curios if my observation's are correct.

Also notice the right angle of the brick bracket in the third pic. If the rod was attached to in the middle of brick bracket any of the lower portion of the bracket below the rod would push the brick away from set as the IT is lifted.

Humbly those are my observations.

Any One care to comment that would be greatly appreciated.

[GianniFocaccia]

Re: Out of work Pizza Man's 42" Build in NJ

I tapered both the top and bottom of my bricks to reduce the size of the horizontal gap on the outside of the oven. I bevelled the sides of each brick on inside and outside faces to reduce the size of the gap on the outside of the oven. I think I ended up with 3/16' joint on the inside, 1/2" on the outside. The plan was to gain a uniform size joint throughout and reduce the amount of mortar I used.

This was extremely time-consuming. And while satisfying to do, if I had it to do over again I wouldn't be so detailed on the entire brick. Just the inside. Homebrew mortar is cheap.

As you gain practice, you will be able to bevel each side of your bricks by eye. You'll be surprised how accurate you can be.

Some guys collect pea-sized firebrick chips and use them as aggregate in mortar for the bigger outside gaps. I collected all my cutoff chips in a 5gal bucket and threw them away.

[kbartman]

Re: Out of work Pizza Man's 42" Build in NJ

I also fixed my IT.

What am I supposed to do with those left over chips? I see some people using them as some sort of spacer in their builds. Are they there to simply fill in voids, and are later cut off with an angle grinder? Can someone explain?

Sorry I missed that last question. I was typing that last post when you ask about the left over chips. I use them as fillers because the high heat mortar I used, specs called for no larger then 1/4" mortar joint which the back of the brick was 3/8" or better. The chips I had just worked out and I did not have to grind them. They were thin enough and just could be broken to size by hand.

[deejayoh]

Re: Out of work Pizza Man's 42" Build in NJ

Spider,
Nice start on your oven. Looking good. Best of luck with your build.

Since the subject on the IT is back in the spot light. I would like to put my 2cents in again. I'm no math or geometry wizard but did played a lot with my "IT" during construction. As seen with the attached pics, I believe the bottom of the brick is the were IT rod needs to connect to brick bracket. I finished my dome with the rod attached to the bottom of brick bracket with full success and no offset of courses. It seems to me and also proved out as seen in the pics that a small offset would still be introduced with the bracket in the middle of brick. It maybe not perceived or as much as the top of brick, But still may exists. I posted a similar observation during the construction of my dome and no one commented. I'm still curios if my observation's are correct.

Also notice the right angle of the brick bracket in the third pic. If the rod was attached to in the middle of brick bracket any of the lower portion of the bracket below the rod would push the brick away from set as the IT is lifted.

Humbly those are my observations.

Any One care to comment that would be greatly appreciated.

The IT works best if it hits in the center of the brick. If it hits on the bottom, the angle is slightly shallow. If it hits on the top, it's too steep. When the plane on the face of the brick is perpendicular to the IT at the center of the brick, each section will be an arc with the same radius.

[kbartman]

Re: Out of work Pizza Man's 42" Build in NJ

The IT works best if it hits in the center of the brick. If it hits on the bottom, the angle is slightly shallow. If it hits on the top, it's too steep. When the plane on the face of the brick is perpendicular to the IT at the center of the brick, each section will be an arc with the same radius.

Thanks Dee,
I really appreciate your response and thank you for helping me gain a better understanding.

Spider, if I may I will try to keep this short in order not to high jack your thread. Hope you don't mind me calling you Spider.

The error of my thinking is in reference to my IT as constructed. Theoretically speaking Dee I agree. I want to point out that as viewed in my picture my brick bracket extends beyond the center of the brick. If one was to attach the IT in the center it needs to be pointed out that any bracket extending beyond the exact center would move the brick outward when lifted when lifted. So mechanically speaking my "IT" as constructed does not interfere with brick set when lifted.

With that said, theoretically the first brick above the over floor would be slightly tilted inward. If the oven floor was dead center of the sphere, and the "IT" pivoted in exact center. I believe it can be said that most builder begin the first course of bricks level to the floor. Anyway I believe I now have a much better understanding of the geometry involved.

I hope this help clarify the point I was trying to make in my observation mechanically speaking. Any bracket extending beyond the theoretical dead center of the brick, would cause the brick to move when lifted or moved horizontally opposite the portion of the bracket extending beyond the theoretical center.

Am I incorrect in my thinking?

Thanks all ,

[deejayoh]

Re: Out of work Pizza Man's 42" Build in NJ

I think in practice there is a bit of slop in any IT so you may get more or less stagger in your build by having it hit the wrong place. I only figured out the angles really worked when I built the spreadsheet model. But there is that difference between theory and practice.

That said, an IT that aligns the axis at the top of the brick is a pretty common design flaw and there are enough builders that have had problems with it later that I try to point it out when I see it

Sorry for the hijack.

[spiderrinaldi]

Re: Out of work Pizza Man's 42" Build in NJ

Thanks for the guidance.

My next question is in regards to the opening arch.

Thermal breaks, buttresses, flues, there is a lot to consider here. Anyone have any suggestions? I don't want to complete another course without settling on a plan.

[kbartman]

Re: Out of work Pizza Man's 42" Build in NJ

My opening arch and thermal breaks are a cross between several builds. I chose a semi circle arch because I thought it simplified things and requires little or no buttressing. I have to give credit to deejayoh, utahbeehiver and Gulf's build's. I'm pictorial in understanding a concept and their well document pictures and album made my build a success. Below is post Utah posted on my thread about his heat break.

KB,

I used Uni Extreme high temp caulk. It is made by McGill Air Seal and contains no hazardous stuff although it was used in an area that does not see food contact. Like DJ I stuff the air gap with ceramic rope and caulked over. I have a floor thermal break, SS tubing, does it make a difference, I don't know since I can't compare as if brick were there.

If you haven't use the Treasure troves link, here:

http://www.fornobravo.com/forum/f2/n...res-15133.html

There are a lot of good builds to study and give you ideas to work out your arch opening heat breaks and over all oven design. Also a special thanks to lburou for putting this thread together. It's key to a builders success and deserves a "sticky"

Hope this helps.

[spiderrinaldi]

Re: Out of work Pizza Man's 42" Build in NJ

How does this look for using as a Thermal Break Rope? Also comes with Cement to adhere the rope to your oven.


http://www.amazon.com/MeecoS-203BK-2...ds=gasket+rope