A generic angle for the dome bricks?

[mpjfitz]

Hello

I have been collecting materials for over a year now and ready to build my oven. All I need now is some good weather so I can start digging the foundations! In the UK there's more chance of winning the lottery

One of the killer deals (?40) I got from Ebay was a water cooled brick table saw. So I can now cut some accurate angles for the dome and the cosmetic brick work.

The dome will have an internal diameter of 42". I was wondering if there is a generic angle I can pre-cut the bricks to? I appreciate that there will be some 'tweaking' in some places. But it would be nice to set up a production line to cut the majority of them

TIA ... Mick

[Bartondad]

Re: A generic angle for the dome bricks?

Hello Mick-
Contact Dmun he is a moderator in the forums and he sent me this: http://www.fornobravo.com/forum/f6/f...cuts-7218.html (More efficient brick cuts)
and it gave a pretty good picture. It allows you to make 3 cuts to a brick that give you the right dimensions you are looking for. Otherwise, checkout the forums, especially the "newbie" forums and you will pick up some great ideas. Good luck with your build.

-Thom

[dmun]

Re: A generic angle for the dome bricks?

There's really no set answer to this question. For a hemispherical oven the taper of the brick remains constant (it's about five degrees for a 42 inch oven and a 2.25 wide brick) but the radial angle changes in two dimensions with every upward chain.

Most of those who build a cut-every-brick dome cut them as they go along.

[Dino_Pizza]

Re: A generic angle for the dome bricks?

Hello Mick,
Congratulations on your saw. Sounds like a great deal. It's an important beginning to building your oven.

As to generic angles: Attached is a pdf of my dome plan showing the angle I started cutting my bricks. It only works if you decide on a full-height soldier course and angle it like I did. My 1st cut along the brick bottoms was 10deg, then went mostly 6 & 7 deg all the way up. About halfway up, I just started to wing-it and sliced the bottom off a brick that got me to an "agreeable" angle, that kept the nice squished-dome shape, yet led me to my final height of 20-21". Then, once I made that brick cut for that row, I just copied it for the rest of the bricks on that ring.

You have to make SOME adjustments anyway because it's impossible to be perfect on the mortar joints (ie: no-mortar showing on the inside, 1/16" mortar showing, 1/8" showing...it tends make your dome higher, or taller, so you have to adjust lest your dome gets over 21").

Good luck on your oven, don't hesitate to ask questions,
Cheers, Dino

[mpjfitz]

Re: A generic angle for the dome bricks?

Thanks for the replies. I hope any cuts will be a breeze with the saw

It appears there is no 'real' set formula for the angles. I'll just wing it

Thanks again

Mick

[Dino_Pizza]

Re: A generic angle for the dome bricks?

Here is my pdf file of the ring angles. I failed to attach it properly before.

[Neil2]

Re: A generic angle for the dome bricks?

"It appears there is no 'real' set formula for the angles. I'll just wing it"

That's it. Once you start you will find that it is simpler that it sounds.

[gdest]

Re: A generic angle for the dome bricks?

Ok let me see if this will help or make sense:
1. To determine the angle of the brick that helps develove the dome use the following formula:
a: Tan A = a/b
What this is is "A" is the angle you want "a" is the height from the oven floor and "b" is your oven radius, i.e. a 42" oven ID the radius will be a constant 21".

2. For the angle on the bricks for the chain is a little more difficult since you don't have a easy way to measure the "a" distance. There are some builds that I have seen that don't cut any angle for either the dome or the chain.

An easier way would be to run a chalk line from the center of the oven to each brick that starts a row or a chain and mark that 1st brick and the remaining should be the same. At least thats what I plan on doing when I start my build.

I hope this helps.

[fxpose]

Re: A generic angle for the dome bricks?

^^^ Like using a chalk line, I plan on using the "indispensable tool" to determine rough cut angles. They should be close/good enough.

[eprante]

Re: A generic angle for the dome bricks?

Search Greg Geisen's build thread (username Geisen) He put some pictures of the wedges he used to cut his bricks. It worked really well. I hope it will work as well for me since I have his wedges and am starting to cut bricks this weekend.
Eric

[DimTex]

Re: A generic angle for the dome bricks?

I can vouch for the value and accuracy of Dino Pizza's pdf, he sent me one for my 36inch build last summer and it worked well for cutting the soldier course.

I know lots of folks use all manner of tools for holding the bricks as you lay course after course. I found that cutting the Celotex foam board I used as a template for the oven floor (36" diameter) into quarters gave me the perfect gauge to make sure the arc of each chain was more or less on the mark and ensured the top of the dome was near to 18 inches or so (actually close to 19 inches). Once the soldier course with its angle cut was in laying the first chain with the template I was able to guesstimate the size wedge i needed to place on the outside edge of each brick and then I cut about a half dozen or so. From then on it was pretty smooth sailing until the last 4 or 5 chains, which were close to horizontal. Then I wedged one of those exercise balls underneath until it was tight and laid the final courses.

If there was one "killer tool" I would say it was a mason's bag. It's like a bakers pastry bag except you use it with mortar instead of frosting. Using one makes it so easy to lay mortar with control and also, more importantly, shoot mortar into gaps and spaces you could not get to with a regular trowel.