39" Pompei build in NH

[ML38]

Russell,

Thanks for the feedback. Because of the winters I will eventually put a pergola with a roof over the oven incorporated into it. It might take me another year or even two but In the mean time, I do have a local masonry supply that I will check into.

If I include acrylic additive of equivalent strengthening ingredient, is this a good recipe? I'm trying to use up the Portland cement and masonry sand that I have so a homebrew stucco would sure help.

Thanks
Marc

[UtahBeehiver]

Someone else will need to comment on this. I did not do this. I believe, David S and Gulf have made some comments regarding waterproofing of stucco and the additions of acrylic to mix whether it was with a home mix or not I do not remember.

[Gulf]

I added acrylic fortifier/bonding agent to my stucco. I used it to replace some of the water in the mix as well as applying it between coats. For a render on an oven, it helps for a good water resistant shell imo. I don't know if this was mentioned earlier in the thread. But, unless fibers are added to the home brew stucco, the first coat will need to be placed on lathe or mesh. I personally believe that the lath or mesh makes for a stronger render. I have no cracks at all in my shell. Or at least there were none before I applied the brick flooring to the dome. I believe that David S recommends the fiber added stucco and a flexible waterproof coating over that should any cracks develop.

Also, don't forget some type of vent so that moisture can escape.

[david s]

Good advice Joe. The acrylic does a great job but is not cheap. It is normally added as 1 part to every 3 parts water, but you can go as high as 1:2 or less if you can't afford it. I also use random AR (alkaline resistant) fibreglass fibres, but as Joe said, lathe is an alternative (just takes longer)

[Gulf]

I would also like to add that for my build, I used hardware cloth for the mesh. The way that it comes off of the roll makes it much easier to conform to the complex curve of the dome than stucco mesh or lath.

[ML38]

Thanks for all the input. I'll look into adding some fibers and acrylic additive..... and I haven't forgotten about the vent. I was going to just put a short copper pipe with a copper 'roof' over it using a small copper post cover (square pointed). Doesn't have to be anything but a path for steam right? Like a valve of some sort, just a short pipe or tube?

On another topic, I've had 4 short curing fires and my dome is completely black except for the soldier row. Is this normal? I don't expect it to clear like when it is at pizza temp but I really didn't expect complete black. Is it because I keep spreading out the coals and wood to keep the fire down making it smoke more?

It will clear eventually right?

On another side note, I'm really happy with the draw of the flue. I was blowing along the floor to get the fire going better and smoke came out the door and when I stopeed, it was pulled back in and up the chimney. Pretty good I think. Also, after the fire died down t ojust a few coals last night, I stacked some fire brick in front of the door. Temp was 350 F and this morning it was 240-250 F. considering the lack of proper seal at the door and that it was only 350 it sounds like good heat retention

[Gulf]

As long as the vent will relieve moisture/steam and keep rain out, it is all good.

Yes the oven will clear eventually. Better later than sooner. Later is more gentle on a new oven's brick as it drys. Completely black is normal. The only reason that the soldier course is not black is that the smoke striates at that level. At about the level of the top of your soldier course is where cool air for the draw of your oven mixes with the hot gasses from your oven. The cool drawn air keeps the smoke from touching these brick. As you know heated air rises.This is also the reason that the oven floor takes longer to come up to pizza temps. Follow the recommended drying schedule and, when it is time, you will start noticing the dome clearing from the top and spreading lower with each passing minute. You may even "smell that smell". That smell is of a super heated oven burning efficiently. No, or very little, smoke will be visible coming from the flue/chimney. The creosotes in the smoke and those coated on the oven walls are now being consumed by the intense heat. That "smell" may be alarming at first, but it will soon become the smell of success. Your oven will go black with soot many times in the future. And you will clear the dome many times. By noticing when your dome starts to clear, you will eventually learn when to stop firng when wanting temps lower than pizza making .

[ML38]

Took the day off from work and did coat #1 of stucco with the color. Figured I test out how dark to make it with the base coat and it would give me a chance to adjust for the finish coat. I added reinforcement fiber to it and I'm tempted to go 2 coats. It will be 1/2"-3/4" with two coats and it already looks good in my opinion. If I use the same S Type Mortar/Stucco (Sakrete) for a second coat and it looks good, can I get away with stopping? Will the finish coat add that much more strength?

Also, had some pretty good fires for 4 hours last night and on-going today. Got pretty hot, not on purpose. couple pieces cranked up the fire unexpectedly. As you can see from the second pic it cleared the dome. After today I think it's pizza time!!!

[david s]

I know it gets exciting when you're just about done, but you do risk cracking the outer shell by firing hard now. It is better to hold the moisture in the outer rendered layer for a week to enhance strength. Especially if the rendered layer is applied over dry vermicrete as moisture will be pulled out of the render from both sides. I hold the moisture in by wrapping the whole oven in cling wrap and leaving it for a week. I usually do blanket, vermicrete, drying fires, outer render, clingwrap, acrylic render, final paint colour. However there are many ways to skin a cat, you do what you can get away with.

http://www.cement.org/learn/concrete...n-construction

[ML38]

Thanks for the link David. I'll look at it later and decide how to proceed. I put the base coat over lath that covers my 3" of ceramic blanket so I wouldn't think there would be a big draw of moisture away from the base coat by the ceramic blanket. I've been misting it today to keep it moist and I will cover it at night to keep the moisture in. It will also gain some moisture from the dew over night. With the exception of the vermicrete I more or less followed what you've done up until now. I went blanket, drying fires, base coat. Second coat tomorrow then decide how to proceed with pizza on Sunday or wait another week...decisions, decisions. I just made some dough to put in the fridge so I'll be ready if I decide to go for it.

Thanks
Marc

[ML38]

I waited on the second coat of stucco and cooked pizza instead. It was a learning experience. Unlike the fire I had on Friday, I didn't get to wait until the dome fully cleared due to time constraint so the oven was not at full temp. It took longer than I though it would. First pizza took 2 1/2 minutes but the 5th and last pizza was like 5 or 6 minutes. I think I let the fire die down a bit too much while cooking and the oven is probably not fully free of moisture. I did add some wood and the temp came up a bit but the floor was down to 500 F by the end.

Kept it simple with a just cheese and a couple pepperoni for my son. They all tasted good which was an accomplishment. The dough was an adventure. I still have some work to do there. 6 dough balls sat in the refrigerator for a day and a half which is supposed to be good but it ended up all merging together to make one big sheet of dough. Managed to get it out and make pizza but it was a challenge. My wife thought if it never got any better that she'd be happy with the pizza. I think she was just being nice.

[UtahBeehiver]

You can also do what we call doming if you want a more darker top. Once the bottom is where you want it and the top could use a little more browning, load the peel with the pizza and lift it up towards the top of the oven, it is hot up there and it acts like a broiler.

[RandyJ]

To keep your dough from merging in to one you could proof it in Ziploc bags or small containers. That is what I normally do that way they are each their own ball.

Randy

[ML38]

To keep your dough from merging in to one you could proof it in Ziploc bags or small containers. That is what I normally do that way they are each their own ball.

Randy

So it's not just my being a total rookie? I'll try seperate containers next time. It was good pizza and I already have several things I need to do to get it better so it's all good!!

Marc

PS: Once I cook a pizza shouldn't I get promoted from Serf???

[RandyJ]

Level has to do with how many posts you have. I do not remember what the tears are. I would think one of the moderators might chime in and let you know.

Randy