Tapered fire brick

[carl]

Hi all
New to this , planning to build my oven this summer I have done a bit of research and spoke to a guy from kiln lining about materials and stuff , he suggested I should tapper the fire brick . How difficult would this be ? Would I have to tapper 4 sides and at what angle for a 42 inch Pompeii oven . I was thinking has any members done this before could anyone give me some advise
Kind regards
Carl

[spinal]

It depends what you use. I used a mitre saw, with a diamond blade (very cheap on ebay - something like £7 for the blade and £30 for the saw). This let me do 90% of the cuts. The rest, I did with a grinding disk with a concrete attachment (and the safety guard removed to get it to fit - DON'T do this).

I know some people have built an entire oven with nothing more than a brick bolster to cut bricks - so it's doable!

I think it all comes down to how tight you want the joints on the inside of your oven...

M.

[bookemdanno]

If you're going to to use ready made firebrick cement, then you need to keep all joints under 5mm in thickness, hence the need for tapered cuts to all four sides. Using the homebrew mortar mix you can get away with plain half bricks with the mortar able to handle the larger joints and perps.
Tapering with both angle and bevel cuts, and creating an almost mortarless dome is the holy grail of WFO construction.
Charliefarleys build is one of those. Look it up in the archive pompeii section.

[carl]

Thanks guys
I am not sure I am upto making the holy grail of pizza ovens so the home brew will probably be the road for me . But what is the mixture ?
Regards
Carl

[kipper]

hi Carl, the tried and tested homebrew mix is. 6:1:1:1 sand,cement,clay,hydrated lime.
use something like and icecream tub to gauge the measurements.
I used a coffee bean container 250 gram which suited me as I'm a slow worker and was enough to do a ring of the dome at a time.
good look with the build.

[carl]

Thanks kipper
That's very helpful , do coffee jars come in 10gr size I am very slow ha ha
Thanks again
Carl

[cannyfradock]

Carl

The homebrew mortar I use is the same as per "kipper"....try not to use fine sand. I have...so far just chopped my bricks in half with a hammer and bolster on my builds....



The homebrew mix will be strong enough to fill even the largest of gaps. This is not the correct way. The correct method is to cut the 4 sides in a tapered fashion (trapazoid cuts) leaving a small uniformed mortar joint, top, bottom and sides. Many members have taken the time to cut the fire-bricks in this fashion and made a fine job of their build. I on the other hand have taken the lazy approach of just cutting my bricks in half and use lots of homebrew. I do however always order a dozen 1" fire-bricks on every build which come in handy for the dome/arch transition and the topping off of the dome. The last 3 dome rings and the key/Cap stone at the top of the dome are quite vertical and almost impossible to complete with just half bricks, so I use an angle grinder and cut my 3" half bricks ...again into quarters and do the same with 1" fire-bricks. I find it easier using these 1/4 bricks to make a good bond at the top of the dome. You should always try to have a decent sized "capstone" at the top.......even if you have to cut it to shape with a 4" angle grinder.

Liam from Kilnlinings may even sell you some 2 sided tapered bricks as he has a proper stonemasonry set-up and he cuts all his own tapered or voussoirs "cut arch" bricks for his modular Vault ovens......

Terry

[pizzaking]

Terry - why did you say not to use fine sand? I've just bought a load on the recommendation of a brickie mate of mine as the sand I had in bags was very coarse / big bits of aggregate in.

Just laid the cooking surface using homebrew made with it and about to start the walls this week.

[sjmbyrne]

Hi all, I'm new to the forum and after a great demonstration by Terry at the Humble by Nature farm at the weekend (many thanks again Terry, it was  a great day), I'm all fired up to build a clay oven in the back garden as a first step to a proper Pompeii model, if the clay version gets the use I expect it to. A question on the Pompeii brick build, where can I find the correct angles to cut the firebricks if I was to go the Holy Grail route rather than use just half cuts? Is there a guide taper angle for a given diameter of oven? Many thanks. 
Stephen

[jms]

Jul 30, 2014 9:17:34 GMT sjmbyrne said:

Hi all, I'm new to the forum and after a great demonstration by Terry at the Humble by Nature farm at the weekend (many thanks again Terry, it was  a great day), I'm all fired up to build a clay oven in the back garden as a first step to a proper Pompeii model, if the clay version gets the use I expect it to. A question on the Pompeii brick build, where can I find the correct angles to cut the firebricks if I was to go the Holy Grail route rather than use just half cuts? Is there a guide taper angle for a given diameter of oven? Many thanks. 
Stephen

FornoBravo oven forums have a guy who made a brick cutting spreadsheet in MS Excel: www.fornobravo.com/forum/f28/dome-spreadsheet-calculator-18131.html. You put in your measurements (in Imperial) and it spits out the required angle cuts.

I used it for my build Another Glasgow pompeii