Cutting Inner Arch Brick Tapering

[UtahBeehiver]

Your saw will not have enough accuracy to worry about 100th of an inch. The key is to spread the joint width adjustments over the entire arch not just the last few joints. These ovens are not exact science or so dimension dependent that there is not some wiggle room to work with. Just get the arch height in the 63-65% range and you will be good. But sure to mark the mortar joints on you support so you know if you start to get mortar creep.

[JRPizza]

Sorry about the decimal inch measurements - I'm a retired Aerospace engineer and that is the units we work in. I still have a few 6 inch scales that are in 1/10 and 1/100 inch. The thing about hemispherical arches in the sizes we are working with is they are usually a little taller than they are wide. This allows you to have a semi-circular arch sitting on some non tapered bricks and have the opening you want (height and width). If you look at my post #6 in this thread you can see how I laid my bricks on end to visualize how the arch would look. I then took my arch form and drew lines representing where I wanted the center of the bricks to be with uniform spacing, like Russel says above. I used the arch form with lines as a guide when I built up my arch. Doing it this way you really don't need to mess with shims - you just butter up the bricks as you go and press them in place. If the center line of the brick is off too much just pull that brick out, scrape off the mortar, and adjust the thickness as needed.

[Michael Harrington]

I think I understand what you are saying I just have to get the dimensions right. So if I cut the two non tapered bricks one on each side ? from 2 5/16 to 1 1/2 and cut tapered bricks 17 total 2 5/16 top full brick size wide end and 1 1/2 small end and adjust morter joint 1/4 + or - I should be good with these measurements .If I cut the two first arch bricks non tapered to 1 1/2 instead of leaving it full size 2 5/16 will that effect how the arch will tie into the dome as It not being the same size as the dome bricks or am I over thinking it.Thanks for your help.

[JRPizza]

I don't think the thinner bricks would change how the arch ties in to the dome, but you could probably make the mortar joints a little thinner and leave the bottom bricks a little fatter. I'll play with the numbers a little and see what I come up with. You have some time as you aren't starting for a while.

[JRPizza]

Michael, the FB plans recommend a 12 inch opening (I believe) for a 36" oven, so you probably don't need to worry about shaving down the base bricks. You also should not be thinking about using shims when you build your arches. I only used them to get a visual of what the arch might look like, but did not use during my build. All you need to do is mark your arch form with the proper spacing and try to keep the joints uniform.