SC Chris's 42" WFO build

[SCChris]

Re: SC Chris's 42" WFO build

Status - November 23.

I had several guests coming for Saturday evening as pizza test subjects. As luck would have it Friday I came down with some sort of crud.. Sunday I felt a bit more normal and ran a combined cure / roast. I have been running up the temp by use of the propane torch and the last burn I had was a maximum of 550f, for several hours, at the end of 20+ hours of heat. Sunday I started the torch at 9am and built the temp for about 1.5 hours and then started adding almond wood. Once I had a good fire I removed the torch and built the temp to 350 at the top of the soldiers. Keeping the fire low, I added a package of beets to roast and 45 minutes later added a rib roast, foil on top, sitting on a bed of roasting vegetables. I rotated the roast twice and brought the internal temp to about 95. At this point I built the fire to a good blaze and browned the roast and pulled it at 129. Rested the roast for 20 minutes and sliced. The beef was spot on! The vegetable were underdone.. Lesson, Pre-heat the location the roasting pan is going to sit. Once the roast was out I added wood and built up to just shy of a full raging fire. After 20 minutes the dome was clear of soot and reading 850.. I sacrificed a quick margarita pizza to the oven, not quite sacrificed it looked like hell but tasted fine.

A great time was had by all!

Chris

PS 22 plus hours later and the interior dome bricks are 408 F. Wahooo!

PSS 46 plus hours and the interior is 230 F, The outside walls of the structure are 72 to 76 the outside of the door is 92 and the underside of the concrete floor, in the storage area is 96.. I still want to add a bit of insulation over the top, because I can, and tighten the door, because it needs to seal. Put in perspective it means if I do a pizza burn on Sunday I can add a pot to slow cook on Tuesday morning and come home to hot braised whatever that night.

PSSS 72 hours and 140f

[geisen]

Re: SC Chris's 42" WFO build

Great build chris.
look forward to seeing the final exterior.

[Dino_Pizza]

Re: SC Chris's 42" WFO build

Chris, your oven is looking good. Nice shape. It's easier to see what's going on with the siding and roof. Good choice with the sticky sided bitumen/rubber underlayment. Seems like good insurance. I appreciate all the work your doing in your slow oven cure. Can't wait to see the real fire in there! Mission tile roof sounds great. What's the siding going to be? Stucco? Great job.
-Dino

[SCChris]

Re: SC Chris's 42" WFO build

Sorry no pictures.

I now have the cement board completely fastened to the base and steel stud walls, no longer just tacked. The intermediate front and rear rafters have been have been fastened to the structure, tacked but primed. I decided on a 4 in 12 slope as that is what the tile roof dictates. I'll be running the roof past the front and back to provide more rain protection. The structure is now chocked full of insulation. The rock wool bats surround the dome, chimney and entry, to a minimum of 5 or so inches and what space was left in the structure is filled with fiberglass attic insulation. I'll be adding venting under the gable eaves to keep things nice and dry. These vents will also give me a way to verify no adverse heat buildup is created. For the roof sheeting, I’m using 1/2 exterior grade plywood. I'll cover this with self adhering 3' wide roll bitumen, rubber, roofing material. I’ll be weather tight at this point and next is the mission tile roof.

When I ran the 20.5 hour burn to 540, I found that heat coming out of the rock wool insulation was perceptible, but not concerning. I don't expect that heat buildup is going to be an issue within the structure with all of the insulation and the venting, but I'll be verifying heat transfer, hopefully the lack of it, when I go to full oven temp. Of course, I won’t button things up before this check.

I’ll have exterior temp numbers for posting next time.

Chris

[jmhepworth]

Re: SC Chris's 42" WFO build

The ambient to high heat burn is when I got my cracks. I thought I had made it through the cure without cracks and then saw them after I really got it up to temperature. But it still cooks pizza even with the cracks, which, by the way, we refer to as expansion joints. I didn't co through anywhere near as prolonged a cure as you did, so you should be OK. If it still cracks, I don't know what more you could possibly do.

[SCChris]

Re: SC Chris's 42" WFO build

After the last report, we all got ready to go "trick or treating" at a friend?s and low and behold my wife has the audacity to come down with the flu. Bummer!! I slept on the couch and checked in on my wife throughout the night. I took Sunday off to catch up on all other things. The burner seems to work ok, better, more robust, at the lower temps, but as the water has been pushed out I see faster upward swings in temp when heating. In my mind, that I could set the burner running and have a predictable flame level over a long period, was if nothing else comforting. I have about 50 hours of running heat on the oven and feel pretty sure that I?m dryer than a hand full of shorter wood burns would have left me. The one thing that the wood burns would have done that I haven?t is the quick thermal shock. Bringing an oven from ambient to 850F or so in 1.5 or so hours is going to be a very different type of burn.

Chris

[John K]

Re: SC Chris's 42" WFO build

Hi Chris

I have recently read through your build and it is fantastic!!

Love the idea of using gas to cure the oven.

A bit of an alrounder I see! Your whole entertaining area is top notch. Looking forward to the rest of the build

Cheers
John

[ThisOldGarageNJ]

Re: SC Chris's 42" WFO build

way to go chris...............

[SCChris]

Re: SC Chris's 42" WFO build

20 hours of burn to as much as 540 Degrees. I now have cement board wraping the sides. I need to get the roof structure in shape and get it all weather proofed, sooner than later. The cement boards up front will be cut to follow the roof line.

Chris

[SCChris]

Re: SC Chris's 42" WFO build

As I'm writing this I have the forth curing burn running. Tonight I'll run 15 or so hours up to 450 degrees or so. As for the structure and insulation, it's a bit rough at this point. I'll be adding cement board to the outside this weekend and this added structure will allow me to tidy the insulation up. Before buttoning up the roof I'll add a bit more insulation in what ever voids i see. I hope to do a pizza burn next Saturday.

Chris

[SCChris]

Re: SC Chris's 42" WFO build

I found a burner at Lowes and ran just under 300 Degrees for 14 hours last night. I put more specifics in the "Firing your oven" forum.

Chris

[SCChris]

Re: SC Chris's 42" WFO build

Update Wed Oct. 22.
I replaced the shop light with a 500W version and had 120 degrees F in the interior this morning. The outside temp was about 55 degrees F. I'm really just trying to keep the dry air moving and the weather working for me. We don't have too many dry air days along the southern California coast so as the saying goes, " make hay while the sun shines". The forcast is for 80 degrees along the coast so I'm hoping that I have a temp of 150+ when I get home. Tonight I'll get a better idea about what LP burner I'll have to use to hold 300 degrees for 24 hours, I may have to run up to walmart for one of the closeout turkey fryers, $20 on sale.

[SCChris]

Re: SC Chris's 42" WFO build

Thanks for the feedback Dino!

The weather at the moment is ideal for curing, warm and dry, so working with what I have at hand and not wanting to push beyond what's prudent, I placed a work light in the oven last evening. I did a bit of fussing with what was left of the arch support, using it as a door, and ended up this morning at 88 degrees in the oven. Although this doesn't seem to be much, its 30 degrees over the ambient temp and the top, exterior, of the oven is about 10 degrees over the ambient. The bricks at the front of the entry are only 5 degrees over air temp, so I feel like I have a bit of gentle drying going on and am using the weather to get a head start. I'll trade out work lights and see if I can hold the mid hundreds in the interior tonight. My hope is to get a turkey fryer burner running Friday night and hold 300 degrees for 24 hours. This would make Sunday morning the start of a 350 degree burn and if I don't insulate on Saturday it'll be Sunday. I'm hoping to do a bit of low temp cooking during these cures..

Cassoulet? hmm?

Chris

[Dino_Pizza]

Re: SC Chris's 42" WFO build

Stonylake: I'm always rootin' for you Michigan folks to have a mild winter. Hope you get one. Actually, I'm also rootin' for us in SoCal to get a wet winter...

I used the straight white vineager with a stiff brush and it worked to a point. Then, I just had to use the pool acid and water mixture too. I agree, it's fine in the oven as long you rinse it.

Chris, backyard is splendid! Looks like a perfect place for friends, pizza and wine. The WFO is nice addition. I wouldn't worry at all about the mortar cracks under your vent anchor plate. It wouldn't hurt to add a little mortar over it when you make your next batch. But it still might still get surface cracks again although that will not matter.

Great job! -Dino

[Lars]

Re: SC Chris's 42" WFO build

Joe,
Good call. That's what I was thinking. ( muriatic= HCl ) If you rinse it off it would be harmless to a pizza or your stomach. If you were especially concerned, one could probably throw a little baking powder on the area after rinsing to neutralize anything that might be left. Just a thought.

L.