WFO CNR Build - Darwin

[Gulf]

My floor birck and insulation layer were both uniform. I did not have to use the 50/50 leveling mix. To my knowledge, you are the second build to have an issue. The first one noted a problem removing the wood brick.

[JRPizza]

I hand selected floor bricks that were similar in thickness. There was a bit of variation but I didn't have to go through that many bricks before I found enough to make the floor. My plan was to avoid using any leveling compound as my insulating board job came out relatively flat, and with the sorted bricks it all worked out fine. You might have luck cutting a piece of 2X4 to the thickness of your final "plug" brick and using it to tamp/smooth the 50-50 so when you drop the brick in it will sit flush. As long as you don't have a friction fit with the plug you might be able to lift the brick back out with a strong shop vac if necessary. If it is too tight it isn't going to want to move.

[terratree]

Did anyone have issues with finally replacing the wooden brick with a real one, when the dome was finished ? Leveling this brick I mean.

Its not like you can simply pull it out again - ya kinda only get one shot. I know JRPizza used this method

I see a potential issue with my floor bricks being quite tapered, and requiring a decent amount of 50/50 to bring level.

Preferred not to have the IT above the floor, but don't want a drip tray (or speed bump) in the centre of my oven either.

Thanks for any help

Jay

[terratree]

Thanks Russell

The penny drops a little more when u can position the IT to see how the intersection works. I still not 100% confident on the intersection with these larger course bricks. One at a time I guess

Bashed up a jig today (half the day), and started on tapering the inner arch full bricks. Quite a slow cut on these. Nearing the top, and realising I didn't quite cut to the template...a bit of shaving or a bigger TDC maybe.

Jig needs a few mods to make it quicker to adjust, but worked ok.

[UtahBeehiver]

Here is a pic from Mr. Chipster on a tapered inner arch, even though his was a partial arch vs a full hemi arch the concept and slope points are the same whether partial or hemi arch. You do need to use a full brick, there is not enough material on a half brick to make a tapered arch. Far as the slump on the hearth, no one is ever going to look underneath and only you will know and "now" the forum members since you confessed.......

[terratree]

Thanks David, will look into that.

I seem to be accumulating loads of nice white fire clay, so at this rate I dont think I'll need a whole lot of store bought stuff.

Back to the build - a few small updates. Form work pulled out from beneath hearth and...... nothing happened That was interesting tho, sitting under a tonne of concrete, hitting out the uprights with a hammer - what could go wrong. Floor is cut, that took the best part of the day. CalSil and thermal blanket have arrived. Foamglas on its way. Didnt start on the brick jig, but gathering material.

A small confession, I totally stuffed up the front edge of this hearth. Was a combination of a mix too wet (very little slump), and not enough vibration in that area. It looks ok now, but Ive covered the truth with mortar (sick of looking at it).

I have a few questions that I would just like some confirmation on:

Q1 - second last pic - Would the template shown be better off being a full brick, to accommodate the intersecting course ? Not sure this matters on the first arch brick. Thinking of going back to the red brick here, as I havent done a proper brick count.

Q2 - last pick re. TDC. Positioning of TDC, just needs to accommodate the full width of the intersecting course (In may case this is 126 mm (4.9"). I'm a bit concerned as I dont know where that course will run yet. I understand its best to tie them in together as courses increase, just hope I have room to intersect correctly.

Appreciate the guidance.

Jay

[david s]

Try Cement Australia
http://sapar.com.au/product/bricklayers-clay-20kg/

[terratree]

Thanks David,

Glad you had minimal flood damage - crazy amount of rain.

So after contacting the manufacturer of that builders clay, they advise its not available in the NT....Typical.

Fishing line and a hammer it is

[david s]

Hi David, thanks for that.

If I cant offload it, do you think the walkers would be ok if let to dry , and then used (bashed) to a powder ?

FYI I paid about $50 for those two and I see the boral clay is roughly half that.

How did you fare in the floods ?

J

Yes you can. Cut it into bits no bigger than your fist with heavy fishing line, allow to dry completely, then crush and sieve it. You will wish you hadn’t decided to though, it’s a lot of work. Much easier to get a bag of already powdered stuff.

Re floods, we live 150 m from the river at a point where it broke its banks. A little inundation in the laundry and garage, but the rest was another 100 mm higher fortunately. Tools in 4wd’s and Army tanks creating bow waves were the problem.

[terratree]

Tomorrow I feel I need to start on a jig , (thanks to mrchipster oasiscdm and many more, I'll be copying these) - the V is slightly showing on course 2.

First two dry run courses cut, without the bevel.

Thanks all

J

[terratree]

Hi David, thanks for that.

If I cant offload it, do you think the walkers would be ok if let to dry , and then used (bashed) to a powder ?

FYI I paid about $50 for those two and I see the boral clay is roughly half that.

How did you fare in the floods ?

J

[david s]

Thank you Russell, I do recall reading 50/50, but wasn't sure what the ingredients were. I have quite a lot of fire clay already just from the 2 cuts in the full 15" brick. Or did you mean the clay for the 3:1:1:1 mortar ?

This is the stuff I picked up for that, fires at 1260 deg c, so I'm thinking it will suit the mortar mix.

Yes the inverted V - I didnt realise the inside dome edge of the bricks were cut as well ? I did intend cutting the taper on both sides to remove the biggest gap, as in the link below. Trying to make sense of the Deejayoh Calc, but I'm not sure I can as I have 3 different sized bricks. Assume inside bottom/outside bottom relate as per pics for course 2 ? So 6.9 degrees to eliminate the main gap. Am I reading this correctly ?

https://community.fornobravo.com/for...nd-tilt?t=2802

Appreciate the guidance !
want
J

Sorry to disappoint, but the Walkers stoneware is not what you want. It is in a plastic state which will make it extremely difficult to combine with the sand. You really want powdered Bricklayers clay, much cheaper and easier to combine with other ingredients. Walkers white stoneware is at the upper end of prepared clays on the expense scale and a large proportion of its weight is water that you are also paying for. Maybe you can sell it to a potter or exchange it for powdered ball clay.
https://www.boral.com.au/products/ce.../builders-clay

[terratree]

Thank you Russell, I do recall reading 50/50, but wasn't sure what the ingredients were. I have quite a lot of fire clay already just from the 2 cuts in the full 15" brick. Or did you mean the clay for the 3:1:1:1 mortar ?

This is the stuff I picked up for that, fires at 1260 deg c, so I'm thinking it will suit the mortar mix.

Yes the inverted V - I didnt realise the inside dome edge of the bricks were cut as well ? I did intend cutting the taper on both sides to remove the biggest gap, as in the link below. Trying to make sense of the Deejayoh Calc, but I'm not sure I can as I have 3 different sized bricks. Assume inside bottom/outside bottom relate as per pics for course 2 ? So 6.9 degrees to eliminate the main gap. Am I reading this correctly ?

https://community.fornobravo.com/for...nd-tilt?t=2802

Appreciate the guidance !

J

[UtahBeehiver]

A peanut butter consistency of 50% sand and fire clay can be used to try and level out taper on bricks, use a rubber mallet and a level to set. FYI, you will need to start beveling the bricks on the dome, the inverted "V" is starting to appear on brick joints "A". You do not need to do the entire side of the brick only the front (dome) portion. Yes, high tech insulation is expensive but not in the sense of the overall cost of the oven.

[terratree]

Waiting on CalSil to arrive from interstate, and debating whether to use foamglas under it. Finalising quotes, that stuff aint cheap huh ?

Whats the best way to level this floor ? I need to raise the low sections 0.35" (9mm), to stop the anchovies sliding off my dough

Pic attached, you can see the wider gap at the high section. What material is best suitable to go between Calsil and fire block ? Was thinking porcelain/ceramic tiles, or a sliced up fire brick, glass ?

Modified the IT yesterday and a bit of dry run to see what the hell I've got myself in for.