New build in Sunny Canberra

[timechanter]

Thats a great idea. Not sure of the timings, but work out well.

[Gulf]

i attempted several techniques to smoke in the WFO. Each fell below my expectations. However, I do find my oven very useful for brisket. For a 10 to 12 hour cook, I smoke in a charcoal/wood smoker for about 3 to 4 hours and then place the brisket (covered or wrapped) in the oven for the remainder of the cook. That requires timing the oven for around 250 F. Mine will drop to 225 F or a little lower by the end of a long cook.

[timechanter]

This weekend is Pizza on Saturday, WFO Bread on Sunday with Soup (or something that goes with bread), and Monday is a 12 hour Brisket (thats being Smoked in a Bullet Smoker, as I found the WFO a little too hard to control).

[timechanter]

Been firing the oven to quite a few "Ooo, that looks dangerous" temperatures and all is fine. Not a mark or crack in the render, I am pretty happy with the threaded brass cap I installed in the outer shell after a few bad storms. The Pot Belly Stove black paint on the flue gallery is working a treat and hides the initial soot really well and cleans up a treat.

I noticed a question earlier on about trying to finish render directly over blanket that must be really difficult. My outer-shell was a mix of VERMICULITE and PERLITE as 10:1 with cement , and finished with a fine sand render. Then 3 months later I cracked it with an "aggressive" fire after being wet and me being impatient. The Betta-Grip was just Bunnings, although that Pointing material looks better and cheaper.

[Steady]

Yes, that one will do fine.

Thanks david s

[david s]

Yes, that one will do fine.

[Steady]

Any 100% acrylic render will do, but be careful because some products (a Dunlop one for Eg) are labelled acrylic render, but are really an acrylic modified cement render, supplied dry in a bag. You need a 100% acrylic product that comes wet in a bucket. I use flexible pointing which is extremely flexible. I find thinning it with water 20% makes a mix you can paint on. It will cover and bridge any small cracks leaving a durable waterproof finish.Keep some to fill any cracks that may develop in a couple of years time.

So something like this?

[david s]

Any 100% acrylic render will do, but be careful because some products (a Dunlop one for Eg) are labelled acrylic render, but are really an acrylic modified cement render, supplied dry in a bag. You need a 100% acrylic product that comes wet in a bucket. I use flexible pointing which is extremely flexible. I find thinning it with water 20% makes a mix you can paint on. It will cover and bridge any small cracks leaving a durable waterproof finish.Keep some to fill any cracks that may develop in a couple of years time.

[Dan W]

Hey Dave, I wrapped the oven in plastic for a week, wet it down every 4hrs or so and the sucker still cracked badly. I can just imagine what's going to happen when I put a fire in. Anyway, think I'll burn now and fully dry out the outer shell then hit it with acrylic render.

What specific acrylic render products are available in Oz? Gripset Betta. Others?

[david s]

Working a render layer over blanket is difficult because the surface is lumpy and flexible. I prefer to cover it with a layer of 10:1 vermicrete( a handful of powdered clay for every litre of cement makes the mix more workable. After 24 hrs the stuff has set up well enough to either fill gaps with more of the same mix or carve some of it back. It’s a nice firm substrate to render on to. Once you have the form back to a nice smooth hemisphere the cement render will make a strong protective shell. You should hold the moisture in this layer to enhance strength. I like to wrap the whole oven in cling wrap for a week. Regarding waterproofing, after around 10 cooking fires the outer shell should be perfectly dry and if you feel inclined it can have a waterproof coating. A 100% acrylic render is a pretty good solution. I find it easier to apply by painting it on and this requires diluting 20% with water. I prefer to use flexible pointing which has been designed to create an extremely flexible layer.

[Dan W]

Hey Timechanter,

Great looking build man. Nice work. I'm in Canberra also, been working on the oven for several years, and also fell into the trap of "too much pizza eating", however, I'm making a final push now. I'm at final waterproofing stage, and put three coats of Silasec over calsil blanket. But for the life of me couldn't get it to set without cracking like buggery, and that's before I even put a fire in it. So I think the membrane is the go. How's the Gripset Betta going after some fires? And where did you find the product? Did you water it down like David S suggested? David S, what products have you used? I was looking at Crommelin Exterior Grade Waterproofing which seemed like about the only suitable thing I could find at Bunnings.

Here's my build BTW: https://community.fornobravo.com/for...ld-in-canberra

[fnbroken]

great job! when's pizza night????

materials noted for later too....

[Steady]

Looks good timechanter, I still need to get a waterproof coating/membrane on my dome

[timechanter]

Its been a while due to way too much (is that a thing? ) pizza eating. Finally correct weather and time to finish the water proofing and feature tiles. Thanks to all, loving the oven.

Before sealing I did drill into the outer shell to install a brass threaded cap for future drying, after cracking the outer dome due to a prior incident with water and enthusiasm. I ended up using Gripset Betta 4L Weather Seal that nicely hides the dome cracks. Then painted over that with external paint colour matched to my windows .

The flue gallery is painted with White Knight High Temp 500ml Pot Belly . I didn't think the weather seal would handle the higher external temps of gallery, so its just a few coats of black.

[Steady]

You can use a 100% acrylic render watered down 20% so you can paint it on. Be careful some renders are marked acrylic but are really only "acrylic modified cement renders" (read the fine print) The 100% acrylic comes wet in a bucket, not dry in a bag. It's also way more expensive than dry cement renders.

Thanks David, I will go looking for some 100% acrylic render