Oven Build in Spring

[cbailey]

Completed the vent arch. The last full brick I used the grinder to take down the leading edge to promote a smoother exhaust flow. I hope to remove the form tomorrow to clean up and point where needed.

[JRPizza]

Opening looks good! Now you just have to plan the transition from rectangular to square for your adapter, and how you plan on attaching it.

[SableSprings]

Wow! Great job on the arch! I really like the clean lines and design you created. Looking forward to your progress and next post. With your evident brick skills, it should be pretty straightforward transitioning to your chimney pipe base plate adapter.

[cbailey]

JR - thank you. Based upon other tremendous builds on this forum, I have good idea of what I want to do.

Mike - thanks for the compliment. What ever masonry skills I have I've picked up during the course of this build. I wish I knew then what I know now!

I dropped the arch support and touched up a few joints. Among other next steps I need to find someone to build me a door.

[cbailey]

I need some advice regarding chimney pipe. I wanted to used Duravent DuraPlus 6' triple wall stainless steel chimney pipe. But I can't find an anchor plate. I'm not sure if Duravent makes one. I might need to go with the double wall SS pipe. To those who have experience, how hot does the exterior of the double wall pipe get?

[UtahBeehiver]

Triple wall Dura Vent Plus (UL 103 HT) pipe uses a 6'' DuraPlus Base Plate - 6DP-BP do a Google search, available several places.

[JRPizza]

We've got 8" double wall stainless, and I don't think it has ever gotten too hot to touch - very warm yes but I can leave the hand on it for a few seconds without getting a burn. It seems to be hottest right where it connects to the chimney. At the penetration of my roof there is about 1-1.5" clearance around the pipe and I used a silicon flashing to provide my water seal up on top. I have never seen any signs of charring around the penetration so I think all is good.

[cbailey]

Thanks JR. The silicone flashing is a great idea. I'm not there yet.

After a few weekends away (my son was married) I was able to get the chimney transition started. I may not get much accomplished this weekend. The forecast is rain, after a week of perfect weather. Figures

[JRPizza]

Among other next steps I need to find someone to build me a door.

Hey, you learned how to lay bricks - might as well learn how to weld too

[cbailey]

I am pretty sure I won't be happy with the results if my welding skills are at the comparative level of my masonry skills at the start of this project! But, then again, it does sound like fun.

[cbailey]

I made some progress on the chimney, finishing the second row. I used the grinder to carve the necessary angle.

Also resumed the curing fires. This day at 350 degrees. It's not easy keeping the fire low, and lit, at this lower temperature. I was using charcoal briquets to start, and small firewood, trying to keep the fire in the target range.

[cbailey]

Started on the insulation. Curing fire at 400 degrees. Tomorrow I might boost to 500.

I am uncertain how I want to fasten the insulation on the arch. I am afraid of using Tapcon screws or anchors for fear of breaking an arch brick. What about using high temperature sealant as an adhesive?

[SableSprings]

I am uncertain how I want to fasten the insulation on the arch. I am afraid of using Tapcon screws or anchors for fear of breaking an arch brick. What about using high temperature sealant as an adhesive?

You've done a great job on this Cory. How are you planning to finish the outside of the dome? Stucco/render? Brick/stone facade? If you are going to do a stucco/render on the outside, having some sort of base wire can be pretty helpful. Many have used chicken wire, perlcrete or vermicrete (to provide better shaping), then the final finish coats (which are pretty thin). Since you have some top slab space available on both sides of the arch, you could use a couple tapcons to tie down some chicken wire at the base and then at the top a piece of wire behind the chimney to the other side. That would secure it enough to set the render in place. David S has just gone with adding fibers to the render for internal matrix support instead of chicken wire (if memory serves me correctly).

If you use a brick/stone facade, then you won't need to hold the batting in place...it will just sit in the gap between your arch and the facade arch.

Since the insulation doesn't need to extend all the way to the front arch face, you're simply looking at making the oven entry look good at this point. Based on the space you have, I think i'd just be setting bricks at slight angle from the front to the back on the sides with a little shave on the front edge to be flush. That would give a nice little flare into your dome finish. I hope that makes sense or at least gives you some options for consideration.

I agree about using "big tapcons" into brick (a little scary...no doubt), but they do make some pretty small "lead" plugs that also would do the job. You drill a small hole into the brick, tap the plug into the hole and then you can screw into the soft plug metal with a regular flathead screw to secure wire. I did this to make a rack to hold my peel and blow stick on the sides of my oven's brick facade. Pictures of the facade and peel resting on L-shaped screws plugged into brick/mortar are shown below.

[cbailey]

I appreciate the compliment Mike, and the advice. I've used Tapcons around the base of the dome and wired the 3 inches of blanket down. I'm in the process of covering with chicken wire. I'll use stucco/render over the dome.

My plan is to make a landing and decorative arch out of used brick. It will look great, but I hate to cover up all the work that went into the vent arch. Oh well, I'll keep the pictures. I like the idea that the blanket will wedge into the gap. I really don't want to drill into the arch bricks. I've used lead anchors a lot in the past. There still is outward pressure on the brick. The left side of my brain tells me there is plenty of strength. The right side is telling me it could break! I think I'll try refractory caulk as make-shift adhesive. The render should hold everything in place.

I'm shooting for 500 degrees this evening while i finish with the chicken wire. There is a small chance for rain this evening (it's been a very wet winter), but the following 3 days with 0% chance of rain. At least I can get some work done in the evenings. Rain is forecasted for the weekend, so it will be a challenge to keep the blanket dry while reaching respectable temps.

Cory

[cbailey]

I completed putting chicken wire over the blanket on the dome. I was able to get the oven up to a sustained average (a bit of an oxymoron) of 500f for four hours. I would love to be able to keep the elevated temps over night, which means, I need to get after a door. Various threads recommend using the dome template and vent arch template as a guide. Of course, if I have the door fabricated to the exact dimensions the expansion of the metal due to heat would result in a stuck door.

How much expansion should I expect?