Cutting Inner Arch Brick Tapering

[Oceanrover]

I've been searching the forum for answers regarding the inner arch brick and how to taper them with the HF Saw on the 4.5" side, I've tried raising the saw and cut as far as I can go then turning brick to finish the cut. This is not working out well and I'm ending up with a brick grave yard.

Can someone chime in and advise the best way to do this. I would like to run a full size 9" brick for the inner arch. I'm dead in the water .

[UtahBeehiver]

I can be done, my bricks were 5.375" wide so had to cut from both sides. On the left I "c" clamp a scrap piece of brick to hold brick from moving sideways, then on the right side I cut some brick wedges to match the correct angle I wanted. Then feathered the brick cuts with the side of the blade any imperfections. You only need the front side to be perfect, You have not mentioned anything about a tapered inner arch. HIghly recommended for ease of tying in dome to inner arch and you need to start out with a full brick to accomplish this. There are some pics in my folder.

[Oceanrover]

I'll take a look at It again, my HF Saw cuts 3 1/2" great but raising to cut 4 1/2 not so good. I'll try as you suggest with clam and scrap. As for the inner dome arch I was thinking of doing what Pizza Bob did (see pic) what are you this on that approach?

Also are you saying I only need to cut on one side of the 4.5" brick, I was attempting to go 4.5" to 3.5" cutting 3/8th on each side??

[UtahBeehiver]

No, you need to taper both sides. I am just saying only the front face needs to have clean cuts, the rest is hidden by mortar. Tapered inner arches are the easier to mate dome to arch, but harder to.understand. But it is your choice.

[Oceanrover]

I must agree that tapered inner arches seem the easier way to go, I was studying that aspect this afternoon.

I may have to get a 4 1/2 masonry wheel for my grinder, IDK this simple cut is frustrating, I wish the HF saw came with a 12" blade version. How are others making this cut on the 4 1/2" side? I know this has more then likely been discussed just wondering if there are any new ideas. I wanted to get the arch done then continue on my 1st course soldiers are up.

[JRPizza]

Here is where I talked about cutting my arch bricks using a similar saw. If you look through my build I tapered enough bricks for my arch in one "process", then used them to build up the arch concurrent with building the sides. I found this easier to integrate. You can see where I dry stacked the arch on it's side to make sure the spacing was right and I had enough bricks. With each row I was able to see what cuts I needed to make on the back side to match the ID of the dome, which I think would have been harder for me to visualize if I had build the arch stand-alone first.

https://community.fornobravo.com/for...412#post382412

[Oceanrover]

So this Is not a straight cut but angled? I was assuming I would cut about 3/8th"s or so making it 2.5" to 1.75"

I did look at your post today JR and attempted, but could not get my jig to cooperate lol....

[JRPizza]

My bricks were about 2.5" across the top and 1.66 across the bottom, giving them a trapezoidal cross section.

[Oceanrover]

This is the same problem I'm having but written better.
At least I'm not alone on this issue-

Arch taper advice with HF saw

I guess I'll try fabricating a jig raise the blade and give this another try. Or just getting a new saw or rent one just for these 17 or so brick$.

[UtahBeehiver]

Understand what you want on the taper to make the arch, this is the first step anyway if you decide to try the "tapered" inner arch (back side) for dome to arch interface (this requires using full length bricks, ie 9" not half length. A lot of builders have been able to accomplish this with both the old and new version of the HF 10" saws, just takes the correct set up and patience.

[Oceanrover]

Thanks Russell, duly noted "

correct set up and patience" I'm heading out to take another stab at this. Yes once I get these first taper cuts I'll use my IT for the inner taper index lines, that should be a straight forward cut (2 1/2" side) I'll keep you posted-Thanks again for your help!

[UtahBeehiver]

Here is pic of how the IT helps you set the angles and alignment. Although this is for a partial tapered inner arch the concept still applies for a full inner arch. The pic is from Mr. Chipster's build. Also note how there the angles change for each brick so you cannot do one then copy. This is further down the road for you but something the brain matter can gnaw on while you do your initial arch wedge cuts.

[Oceanrover]

Yes I was reading yesterday where the builder set the bricks in shims and marked one brick at a time thus making the cuts match the IT. I believe you were mentioned in that thread.

[JRPizza]

I'm making this post to help Michael Harrington with questions about tapering his bricks. This thread seemed like a good place since the topic is brick tapering. In the attached spread sheet, it shows for a 36 inch oven with bricks of his dimension (2.3125X4.5) he can make a 17 brick arch with .28 thick mortar joints, where the fat part of the brick will be full 2 5/16 wide and the narrow bottom would be 1.48 wide. I believe he had gotten some different dimensions from the angleizer program so I wanted to show there are lots of ways to do a hemispherical arch. If he uses the dimensions I came up with, and sets a 17 brick arch on top of a full thickness (2.125) brick on each side with 3/16 thickness on top of these bottom bricks his opening will be just at the 12" recommended by the FB plans. I would probably shave some of the thickness of the full bricks to get closer to the 63% height ratio that is said to be ideal. If the bricks are cut to about 1.5 thick the .28 joint thickness could be used for all the arch and the resultant height would be close to ideal.
Hope this helps.

Inner	Brick	Radius	Circumference	Circumference
Radius	height	outer	Inner	outer	# of bricks	t joint	Brick W1	Brick W2
9.5	4.5	14	29.85	43.98	17	0.26	2.3125	1.48

[Michael Harrington]

I want to thank you guys for the help,of course I do have questions.If I try to go your way JR If I cut bottom bricks on both sides from 2 /516 to 1 1/2 17 bricks cut to your posted size the morter joint .28 which is 9/32 ? 7/25 ? just over 1/4 ? I could use 1/4 inch shims and make up the half inch as I go up. Math is not my strong suit never had to use a odd numbers like .26 .28 with morter I think it would be easier to use 1/4 3/8 but cuting the bricks to that size full size one side would also be easier. I am sure this does not make sense let me know.