Michael's 42" in Portland

[mklingles]

Re: Michael's 42" in Portland

Well I finished my dome over the weekend. Unfortunately I didn't read Tscarborough's comments before. So, I have a less then ideal bond pattern on my courses. It's gonna have to be "good enough" because it's done .

Pictures in a day or two. Chimney design thrusday. Chimney construction this weekend.

Question: If I build up the vent opening and front arch on Saturday, is it safe to build a 3-4ft tall brick chimeny on top of it on Saturday or Sunday? Or should I wait a week for the base vent opening to set?

[Nic The Landscaper]

Re: Michael's 42" in Portland

You will likely have to temporarily buttress the sides of the front arch to prevent them from kicking out as you build the chimney but it is perfectly safe to do it same day. If you wait until Sunday you probably wont have to buttress the arch, but if your not confident its easy insurance.

I would wait to start chimney construction until you felt confident to pull your arch form out. I pull my arch forms as soon as the mortar is firm enough to start tucking which can be as quick as 30 minutes after setting but most people like to wait a little longer than that.

[mklingles]

Re: Michael's 42" in Portland

Made less progress then I hoped last weekend, but hoping for two good days this weekend. With a little luck I'll get the vent opening finished and chimney up.

I did get the front arch and a good portion of the vent opening completed last weekend.

Pictures comming.

[mklingles]

Re: Michael's 42" in Portland

Let's see. 3 weekends ago I finished my dome. Here's two pictures.






On the outside picture you can see the wires for two thermocouples in the dome. There are 4 more in the floor (never enough data).

So far so good.

[mklingles]

Re: Michael's 42" in Portland

2 Weekends ago I built the front arch and started on the vent. It was really not in Portland so I didn't get as far as I hoped. The front arch is made of stone. It's the only finish work I'm going to do. I plan to cheat and have a stone mason do the finish work on the facade stone. I lack the patience to do finish work well. I did make sure to take my time on the stone arch. Wow what a world of difference cutting fire brick (butter) and stone (well rock).



In the next picture you see the start of the oven vent. I went for straight sides between the dome arch and front arch. You can see I'm starting to angle the sides in at a 30deg angle. This will form my smoke chamber as it closes in on the sides and from the front to form a 7x7 opening for my 8 inch chimney flue. 7x7 is the inside dimensions.

[mklingles]

Re: Michael's 42" in Portland

So that brings me to last weekend. I finished the chimney vent / smoke chamber and the chimney. Although pictures of the chimney have to wait. (It was late; I was tired.)

Here it is from the outside. This is with 2 feet of flue. I added one more for 3 feet of flue. I think this will draw fine, but can go higher if I need to. If you look close you notice a piece of steel angle iron to distribute the weight of the chimney across the front arch. This might not have been necessary, but the first straight course in the next picture down only overhangs the front arch by about 1 inch. I was to lazy to build that inner fire brick as a proper arch.



Here's the view looking up the vent. The sides and front slope in at a 30 deg angle. The back actually slopes backwards for one brick course, because I want to end up with the front arch sticking out slightly from the stone facade. The inner arch opening is 18" the outer arch and side vent walls are 19". I thought about casting this in perlite and cement. The arch + vent up to the chimney took me a day and a half. I thought I could do it in 1. I think I could have done the arch and form in 1 day. Anyway, I am very happy with the result.



One more smoke chamber picture. This one also lets you see most of the dome. The first straight course above the inner arch slopes backwards. That's less then 30deg. I just moved it back about an inch to push the chimney back a bit.

[brimbleshoes]

Re: Michael's 42" in Portland

I'm up in Vancouver --

Which Mutual Materials store did you purchase the firebrick from? I went to the one here in Vancouver and the guy there didn't know if they were medium or heavy duty brick. I'm so new to this that I don't know either.

What about your other materials, where did you source them?

[Nic The Landscaper]

Re: Michael's 42" in Portland

Mutual Materials sells medium duty fire brick. They can order in heavy duty and larger fire brick tiles, 12"x12" and 18" x 18" but they all cost an arm and a leg.

[mklingles]

Re: Michael's 42" in Portland

I got firebrick, flue pipe, standard red clay brick and heat stop 50 from Mutual Materials. They had to transfer the heat stop 50 from one store to another for me to pick up.

Their cinder blocks cost about half as much if you buy them at home depot, so I got rebar and cinder block from HD.

The Mutual Materials is a 5 min drive from where I work and home depot is on the way home, so I didn't spend the time loooking around for lower prices.

[Nic The Landscaper]

Re: Michael's 42" in Portland

I got firebrick, flue pipe, standard red clay brick and heat stop 50 from Mutual Materials. They had to transfer the heat stop 50 from one store to another for me to pick up.

Their cinder blocks cost about half as much if you buy them at home depot, so I got rebar and cinder block from HD.

The Mutual Materials is a 5 min drive from where I work and home depot is on the way home, so I didn't spend the time loooking around for lower prices.

The funny thing about this is that Mutual Materials manufactures and distributes most of the concrete building materials to Home Depot here in the northwest. And I agree and have also noticed that Depot's prices are way better than Mutual's. Even at whole sale prices Mutual Materials is more expensive than Depot. It just kind of makes me wonder what is going on behind closed doors sometimes......

[mklingles]

Re: Michael's 42" in Portland

Just finished the first fire!! Very excited. Should be able to cook in a week.

Spent the day with a friend welding a structure to hold the roof up. Didn't quite get done, so we'll finish next weekend. Then with the structure in place I can measure and order the roof. I'm going to use a single piece of blue stone ~4' x 3' x 1" for each half of the roof (like one big shingle )

[Dino_Pizza]

Re: Michael's 42" in Portland

A single piece of stone for each half of your roof sounds awesome. Can't wait to see it.

BTW: very nice flu transition. It's going to draw smoke up it very nicely. Congratulations on your 1st fire. Take your fires slow and keep an eye out on it.

-dino

[mklingles]

Re: Michael's 42" in Portland

Thanks Dino. I'm excited too. The flue does draw nicely. Here's a few photos from my fourth curing fire. When the wind blows in my yard it blows straight into the oven. Then smoke puffs out the front. I suspect it's not downdraft on the chimney, but rather just a big push of air into the dome forcing smoke out the front. Could be down draft though. I'll eventually add a cover above the chimney which may help.

[mklingles]

Re: Michael's 42" in Portland

Curing is going well. Might have a few hairline cracks towards the back of the dome.

I got the roof structure finished with help from a neighbor who did the welding. It's made primarily of 1 1/2" square tube with angle Iron for the "rafters". Some 1" tube at the front.

[mklingles]

Re: Michael's 42" in Portland

I have a question:

The steel frame will be covered with Hardibacker and the entire enclosure will be covered with facade stone and sealed on the top with two pieces of 1" thick blue stone. My question is should I leave a vent (I'm thinking 4"x8") in the back of the enclosure (with a screen) to let the interior / insulation breath?