John's 42inch Aussie WFO

[John K]

Re: John's 42inch Aussie WFO

Hi guys.

Everybody's ideas are great but I would be cautious with utilising non water resistant tools around water. You might get a kick you weren't expecting!!

I found a guy based in South Australia who will arrange to deliver a new Brick saw to my home (Syd) for $880.00.

After I finnish with it I will sell it on ebay so even if I get $500-$600 for it I will have done okay considering hiring one cost $150 a day plus blade wear and tear.

I will post some picks once to hand.

[nissanneill]

Re: John's 42inch Aussie WFO

3G,
you can also try to deflect the dust into a large plastic bucket/crate through a water spray to settle the dust. I would be careful using a quality saw (compound mitre) to ensure that no dust gets into the motor, nor the rails get wet and either rust or corrode, A good wipedown with CRC or WD40 will suffice.
Look, the angles that you cut are NOT CRITICAL as you can always use a little thicker mortar/adhesive, rather than getting an almost dry fit!

Neill

[3G_]

Re: John's 42inch Aussie WFO

Ive got a wood cutting compound mitre saw which im considering using. Can adjust angles both ways. Maybe a good soaking of the bricks and a fine spray will do it (along with diamond blade). Ill give it a go and report back with pics.

[kombiman]

Re: John's 42inch Aussie WFO

As far as the cut off saw, set up besides the blade a fine irrigation sprayer and no dust! Cheap and easy even if you but new, Bunnings for a saw and ebay for a diamond blade, possibly $2-300 all up! Soak your bricks in water and just don't spray the motor with the water.

Solid gold post! We Aussies dont have the harbour freight saw option. Minimum = $600 for a wet bricksaw

[ThisOldGarageNJ]

Re: John's 42inch Aussie WFO

Hi John k

Whilst I am trying to source a bricksaw to begin the dome I thought I would start on the "indispensible tool".

If your just cutting your bricks in half a good wide bricklayers chisel will do a fine job.. Its just one good shot with a hammer.... The inside finished face go to the oven and the rough cut is hidden under the dome render..

Angle cutting takes some practice though,, Thats where your hand grinder will help..

Are you planning a lot of intricate cuts ?

Mark

[nissanneill]

Re: John's 42inch Aussie WFO

John,
The final render that I used was simply a waterproofing render as listed on the bags of Portland cement. 1 part portland to 3 sand, rendered to around a half inch thick.
I am yet to find (but haven't been looking too hard lately) some 2" mosaic tiles to finish the dome, (most have been in 'pool and spa' colours) but might just leave as it is and continue the new outdoor kitchen/patio roof over the oven:

https://www.fornobravo.com/forum/f35/neills-new-kitchen-underway-4591.html

As far as the cut off saw, set up besides the blade a fine irrigation sprayer and no dust! Cheap and easy even if you but new, Bunnings for a saw and ebay for a diamond blade, possibly $2-300 all up! Soak your bricks in water and just don't spray the motor with the water.

Cheers.

Neill

[John K]

Re: John's 42inch Aussie WFO

Hi Neil,

Yes I heard the unfortunate news of Paul's Passing. I also read that both Paul's bricklayer and yourself had begun work and have nearly completed his project. I think that it is absolutely fantastic that you are able to assist his family, Well done!!

The "Indispensable Tool" was a brilliant idea from Paul and has come a long way since then with people refining this as they see fit. From my perspective as I have no brick laying experience I think it will be perfect for me.

The idea of a cut off saw had crossed my mind but the amount of fine dust that would be generated would be substantial. I have located a bricksaw for about $900 and am currently trying to reduce this amount.

Your build looks great and I cannot believe you nocked most of it up in a couple of days!! I have a question around the render finnish. Have you added some type of water repellent to this to avoid moister penetration?

[nissanneill]

Re: John's 42inch Aussie WFO

Hi JOhn,
these devices that were initially made popular by Paul (Hendo) Henderson (deceased) are good if you want a perfect hemispherical dome and take a lot more time to build your oven. I spend some time after Paul died finishing off his oven with his brickie (Dallas).
With a little care, you can build your dome in a weekend and have a very practical good performing oven. Yes, I had a commercial brick saw to cut the 120 or so fire bricks in had and finished the oven in a week-end. Check out my build at:

http://www.fornobravo.com/forum/f8/neills-pompeii-1-a-2005.html

Follow the prompts on the last post to follow it through completely.
I guess it depends on the individual as to what or how they want to go. The domes don't need to be 'perfectly symmetrical' to work well, as some have lower or higher domes for different cooking characteristics.
I also used a 9" angle grinder with a diamond blade but why not look at buying a 14" diamond blade through ebay and putting it in a 14" metal cut-off saw. With a fine water spray on the wet brick will not make much mess and safe and easy to cut for a minimum investment. Check out a "brick saw" search on ebay

Neill

[John K]

Re: John's 42inch Aussie WFO

Whilst I am trying to source a bricksaw to begin the dome I thought I would start on the "indispensible tool".

My brother Inlaw and I have found a ball joint nut that we have modified and will be used as the central pivot point. A length of steel rod has been cut to the appropriate size and a threaded hole drilled to one end of the rod.

The ball joint nut is then screwed to the rod and allows for 360 deg movement

On the other end we have welded a standard nut to the steel angle which then screws in to the rod.

[John K]

Re: John's 42inch Aussie WFO

Hi all

I am trying to purchase a Bricksaw somewhere in NSW and am hoping somebody has one they would like to sell or can recommend a cheaper unit I could buy.

This is holding me up from beginning the dome and cooking floor construction.

Cheers

John

[John K]

Re: John's 42inch Aussie WFO

You got me thinking so I jumped on their web site Field Furnace Refractories

And found this commentry under Insulation bricks. seems the lowest rating begins at 900oC.

INSULATION BRICK

Field Furnace Refractories is an agent for ISOLITE Insulating Firebrick.
The Insulating Firebricks have densities ranging from 0.50 -1.8 grams per cubic centimetre and temperature ratings from 900oC to 1800oC.

Isolite Insulating Firebricks have low thermal conductivity good cold crushing strength; low reheat shrinkage and excellent dimensional tolerances.

We can supply the insulating firebrick required for any furnace design to give optimum thermal insulation. Isolite IFBs are used as back up and as a hot face in a myriad of furnaces and kilns.

[ThisOldGarageNJ]

Re: John's 42inch Aussie WFO

Im wondering if the block are higher rated for insulation as vermic, will I get more insulation in less space,, dont worry I will do some more research here, appreciate the offer,,,
Mark

[John K]

Re: John's 42inch Aussie WFO

Not sure about direct heat but I would be more than happy to send an email to the supplier and ask if you like?

Otherwise as you said place the insulation bricks behind the Firebricks.

[ThisOldGarageNJ]

Re: John's 42inch Aussie WFO

i just wanted to be see if the insulating fire brick could take direct flame ? I will Probaby put them behind the firebrick, better off i think.....

[John K]

Re: John's 42inch Aussie WFO

Hi Mark

The supplier actually recommended the bricks over the Vermiculite (probably as they make more $). I did ask the same question about strength to which he advised that as long as I mortared down the Insulation bricks that sit under the Walls of the oven I will not have any issues.

I have seen 20 odd ovens built by them/their customers (photos) that used bricks over vermiculite so can only assume that they are strong enough. I guess I will find out shortly!!!

I am unsure if your can cut these with a hand saw but can confirm that they are very light items.

How heavy will your fire box be? Will the load not be distributed across the Insulation evenly?