36" Pompeii Build Redux - This Time In CA

[NCMan]

Great job you are doing. Have loved following your build. Best of luck to you and many years of enjoyment!!

[rsandler]

Pulled the damp towels yesterday, and I'll start curing with the light tomorrow. In the meantime, finished my vent, and also my door. Four coats of spar urethane on the walnut front piece, and a whole bunch of Liquid Nails Extreme Duty between the wood and the Nomex to bond them. With my initial tests of hefting it about, the combination of adhesive and stitching seems to have done the job to keep it as one cohesive piece. Weighs in at a bit over 11 pounds, not bad for 4 inches of insulation (the CalSil pieces alone weigh about 7 pounds).

Most of my chimney parts arrived except for, annoyingly, the base plate, which I ordered the wrong one of. Ah well; means I can be more patient about the mortar on the vent hardening up, reducing the odds that drilling the tapcons shakes something loose.

[rsandler]

Had the light in since yesterday afternoon, got the dome as high as 150F. Today I put on the blanket insulation. Despite doing a pretty good job (I thought) of cutting it to fit tightly, I ended up with way more than I really needed. Three 25' rolls of Morganwool got me 4" all around and something like 6 or 7 on top. Should get pretty good heat retention! This afternoon, after the insulation had been on for a couple hours, the dome registered 170F just with the light. Not sure I need to bother with heat beads, but I'll keep the low heat going for a while.

Also pictured: During the partial eclipse we had yesterday in the Western U.S., my elder daughter found a better use for my masonry grinding wheel.

[rsandler]

That halogen work light (acquired from my dad, who found it on the side of the road years ago) is doing yeomen's work on curing in combination with the insulation and my door. This morning the oven floor was around 200F, the dome was at 220F and I could see steam in the rays of the light. Could just about smoke something at those temps! Firewood delivery comes this morning; I'll still start small, but I feel pretty good about a 300F fire not generating too much steam!

[UtahBeehiver]

Just be gingerly when using wood, one extra piece of wood will spike the temp. very quickly and potentially crack oven.

[rsandler]

Fired for about 6 hours yesterday using one piece of kindling at a time. Temps bouncing between 300 and 400 at the dome, though when the active flame went out, as it did periodically, the temps pretty quickly dropped toward 300-350. Really glad I did 24+ hours with the light and that the light got it so hot (dome was 240F when I pulled the light) as I think that helped get a lot of moisture out. Some wisps of steam were visible rising from the CF blanket after it got dark, toward the end of the firing, but not the big clouds I remember from the first 300F firing on my first oven. No visible cracks by the end of the firing; I'll see how it looks this afternoon. Took a quick look with the IR thermometer during a stretch break from work, and the dome was still at 250F after having had the door on all night.

Plan for today is to go a little hotter, aim for 400, allow up to 450.

[rsandler]

Having a real struggle keeping curing temps in the desired range, but otherwise so far so good--no cracking visible, no water vapor coming out of the blanket either today or yesterday. Yesterday I was aiming for 400-450, and hit more like 450-500, about 5.5 hours of fire. Today I tried to repeat yesterday, and ended up getting 450-550, with the ceiling getting to around 600 at one point around the 5 hour mark. Hard to get my fire much smaller, so I just rolled with it. After spending a few hours with the dome at or above 500 (not counting however long it stays that hot with the door on) without ill effects, I'm thinking I don't need any more curing fires, particularly in light of the lack of steam?

Unless I do another round of fire tomorrow, I'm thinking that I'll wait for the temps to drop below 400, toss in some firewood to kiln dry, and aim for a pizza fire on Saturday.

As far as other aspects of the oven, the bare vent is drawing decently well, but I'm really looking forward to getting the baseplate for the chimney so I can get the smoke out of my face. I suppose once I'm not trying to keep a teeny tiny fire that's on the verge of going out, I'll get less smoke in the first place. The door is so far working great; the Nomex cover is holding up just fine, though it hasn't been exposed to super-high heat yet.

Started working on the enclosure, cutting track for the metal studs, but nothing picture-worthy as yet.

[rsandler]

First pizza bake went well! Invited my parents over and baked five pizzas. The dome cleared a little slowly and a little unevenly compared to my first oven (some dark patches remained here and there) so possibly still a little wet, but I didn't encounter any cracking. This will be the real test for the Nomex door cover, as I extinguished a full pizza fire with it.

Also pictured: studs of my enclosure (still need to cut, fit and screw on the top tracks, before adding the roof), and some dumb oven completion memes

[hankplank]

Amazing pizzas! I've not tried making five pizzas in succession like that. Did you do two or three at once or just one at a time? Your oven looks like it could fit three if needed. Your pizza making skills match your oven building skills.

[rsandler]

I'm a muddle-it-through kind of builder, but I've had a lot of practice with pizzas over the years, as this is my second oven. My approach to multiple pizzas is overlapping generations. Put one pizza toward the back of the oven, then turn it about a third and pull it to the front once it starts to color on the fire-side edge. Then a second pizza goes in the back. Usually works out that the first pizza is fully baked around when the second starts to color, and on you repeat from there until everything is baked. I've done a dozen or more in sequence at pizza parties this way, usually limited only by folks having their pizzas topped and ready to go in.

With smaller pizzas you might be able to fit three at a time, but the coordination of what to turn when gets pretty challenging. That's part of why I had no interest in building a larger oven than a 36" the second time around--sure, I could fit more pizzas at once, but how would I turn them all?

[Giovanni Rossi]

I agree. I could easily fit 5 pies in my 42" but trying to manage that many in sequence is just silly since they bake so quickly. I built the large footprint for bread baking.

[rsandler]

Finally got my chimney base plate this week, so I have a chimney at last. Hoping that will get the smoke out of my face on the next fire-up. Over the course of the week I got my enclosure all framed up, finished attaching the roof structure today. Started to cut down cement board for the walls, but haven't put any on yet; probably get to that this weekend.

Aiming to get a full roof on before the rains start in for real; in non-drought years it can rain almost daily from November through March. Since I (more or less on purpose) made the pitch of the roof so low, I'm basically down to flat roof materials as options on top of the cement board roof deck. Thinking about just hiring a roofer to do it, if I can find one who will do a job that small. I think what I might save in labor doing it myself I'd lose in materials costs for adhesive and such that I can't buy in small enough quantities and wouldn't be able to re-use the excess (never mind that a real roofer would surely do a better job than I!).

Planning another round of pizzas tomorrow, this time inviting the neighbors :-)

[rsandler]

Got my enclosure walled and roofed over the last couple weeks. Putting cement board on 20ga metal studs is a pain in the neck, let me tell you; even with special self-drilling cement board screws, getting the fasteners in without completely destroying the edges of the board was an exercise in frustration. Once I had the boards up and the joints taped with thinset and mesh, I filled the enclosure with a whole bunch of loose perlite.

For the roof, I ended up going with a "peel and stick" asphalt rolled roof, and did it myself. I had two roofers out; one wanted $1100 for the job, the other said he didn't know how to do a roof on cement board, but when I suggested the peel and stick approach, said that would work, but he didn't use the stuff. The roof roll and accessories were under $200, so pretty reasonable. Got the roof on just in time for some heavy rain (literally; started pouring about 30 seconds after I pressed the last strip of roofing into place). Seems to be holding up!

Also finally (if belatedly) got my permit for the oven approved by the city planning department, ending a 5+ month odyssey. Now I just need the building inspectors to sign off (my town takes permitting seriously to an unbelievable degree). Got the roof framing signed off before the roof went on, so theoretically I should be able to get a final inspection soon.

For the oven itself, heat retention is looking fantastic. Made a third round of pizzas this past Friday, with just enough fire to get to pizza temperature and make four pizzas for dinner. Despite that, the dome was over 440F the Saturday morning, and around 375 Sunday afternoon when I got around to cleaning out the coals to toss some firewood in for next week. Good stuff!

Going to try to get the raised platform for the landing counter poured this week, so that exposed rebar will finally be enclosed, but after that I figure to be done for the year; counters and exterior finish can wait for the spring.

[rsandler]

Formed and poured my landing platform this week, using a mix of materials to get the shape I wanted. Came out reasonably nice, though I wasn't quite as attentive in getting rid of voids as I could have been; partly a consequence of needing to mix more concrete after a single 60lb bag almost but not quite filled the form. I'll fill the voids with some mortar, I think. Longer term I'm thinking small glass mosaic tiles would look nice, so the surface just needs to be smooth, not pretty.

Heat retention continues to be pretty marvelous. Made pizza again on Sunday, and since I planned to make bread, I added two additions of wood (three logs total) after finishing with pizzas. This morning the oven was over 550F inside. Had to leave the door open for a half hour to get the temps down to around 500F, so I could bake a batch of sourdough without scorching the bottoms. Next time I'll add a bit less fire, or plan a batch of baguettes to take the sting out of the floor before loading larger loaves.

[Giovanni Rossi]

Great looking loaves! What was the bake time?