36" in Seattle

[kebwi]

Re: 36" in Seattle

Cut the bricks for the fourth curved course. First work since last Thursday. I was snowboarding all weekend.

[ThisOldGarageNJ]

Re: 36" in Seattle

hey keb,,,
Try doing some research on copper gutters, They still make them and they are generally copper screwed and soldered together where there are seams... I do have a soldering iron for that (electric) and would be happy to loan it to you if you need to go that route.. Im hoping for you theres an easier way... It would look very cool though
Cheers
Mark

[kebwi]

Re: 36" in Seattle

Hmmm. It seems like an elliptical hole in one slat of the roof would suffice. Copper rooves are generally made from individual slats, about 12" wide each. I'm unclear how to seal the seams and lots of othere details, but would't the steel pipe just project through a hole with some sort of flashing around the edges?

I admit, my thoughts are preliminary at this point.

On a different topic, this external wall. It would be (I'm asking) steel studs tapconed to the hearth, with cement board, layered in ledgestone. The ledgestone will obviously let a lot of moisture through between the stones, wind-driven rain, piled snow, etc. Sooo, cement board can be directly exposed to water like an almost-external wall? Or am I misunderstanding something about this constructiion process?

Thanks.

[dmun]

Re: 36" in Seattle

I think filling the enclosure is easy and foolproof. If there are areas you don't want to insulate you can always block them off with cement board. I think the copper conical roof is great too, although it makes the chimney transition a bit of a challenge.

[kebwi]

Re: 36" in Seattle

Thank you for the kind words everyone. I'm still trying to determine how I will handle the next stage. I am leaning heavily toward a nonigloo enclosure. What I really want is a "tuna-can" building in ledgestone about 67%-100% the dome height with a copper conical roof.

The other thing I'm still figuring out is the insulation. I have loose fiber, not a blanket, which should be easy to coat over the top, but I'm unsure how I would hold it to the vertical sides (chickenwire wrap perhaps?)...so I was thinking of building the outer wall that will back the ledgestone and then filling the cavity with loose vermiculite up to the curve where I can transition to the bulk fiber...something like that. I have tons of both (loose bulk and vermiculite) so I'm trying to decide on the best method to pursue.

Suggestions are welcome.

Cheers!

[dmun]

Re: 36" in Seattle

I don't usually chime in with "I love this build" choruses, but I really love this build. I love the no-soldier construction method, I love the alternating brick semicircular arches, and I love the seriousness of anyone who would cut mortar grabbing lines in bricks, whether they're needed or not. This is going to be a great oven.

[Neil2]

Re: 36" in Seattle

"This is basically unnecessary as I am also cutting my bricks such that they are pretty much self-supporting...but I'm paranoid, so such as it is."

Looks good.

[fxpose]

Re: 36" in Seattle

That dome is shaping up very nicely! I like it.

[ThisOldGarageNJ]

Re: 36" in Seattle

keb...

looking good.... You'll be closing your dome before you know it..

Cheers
Mark

[kebwi]

Re: 36" in Seattle

The second and third curved courses are up!

The third photo shows some details of my technique. First, I shove brick wedges into all possible gaps. Namely, vertically between adjacent bricks of a given course and horizontally between a brick and the brick below it. In addition, starting with the second course, I am gouging oblique slices out of the tops (and bottoms although you can't see it) of the bricks, with the gouge pointing out from the oven, such that any gravitational pressure of the brick to slide radially will catch against the mortar. This is basically unnecessary as I am also cutting my bricks such that they are pretty much self-supporting...but I'm paranoid, so such as it is.

Cheers!

[kebwi]

Re: 36" in Seattle

Interesting, so the perception of weight difference was purely psychological. I'll have to measure them myself. I have also noticed the sparks, although I hadn't noted that the darker bricks sparked more. I'm sure I will now that you mentioned it.

Ta.

[tfasz]

Re: 36" in Seattle

Aside from appearances, do you also agree with me that the darker bricks are notably harder and perhaps imperceptibly heavier?

Yes - they certainly are harder and I find I have to take it about twice as slow cutting them. They also seem to give off some sparks when cutting (even on the wet saw).

I had not really noticed a weight difference, so I threw some on my kitchen scale tonight and both the darker and lighter bricks all where in the 3.2-3.3 kg range. One of the light colored ones was the heaviest of the bunch.

[cynon767]

Re: 36" in Seattle

For me, the increased fireclay hasn't been a problem thus far. I wanted to keep the portland content slightly lower than the basic formula on the theory that the final joint would be weaker once the portland burned out. I let the mortar have a long drying time before firing to cure, approximately 6 weeks of sitting while I worked on the other aspects of the project; it has not shown any sign of cracking, either during drying or in the heat curing. I think that, with the high clay content, this slow and steady process may be helping prevent cracks. Hard to test, but that's the premise I'm working on.

I always assumed that one of the reasons an equal part of lime is added to the homebrew recipe is to counteract the shrinkage of clay; Lime increases both stickiness and plasticity of the mortar, making a weaker bond with the bricks than porland but a joint which is more flexible and less prone to shrinkage cracking. It also doesn't break down at wfo temps like portland does.

I have done a little preliminary research on this, and am doing more now; I will post the results in the mortar thread.

[kebwi]

Re: 36" in Seattle

Not to dwell on this, but for informative purposes of future readers of this thread, here is another thread (started by myself no less) which contains multiple independent claims of various recipes which contain higher than 1:1 fireclay/portland. I'm not saying any of them are right or wrong or that recommendations to the contrary are right or wrong; I'm just pointing out how I got into the position of increasing the fireclay in my own mortar in the first place, for better or worse.

[kebwi]

Re: 36" in Seattle

Yes - I bought my bricks from the same place (I-XL Masonry | Showrooms - Redmond, WA) and have noticed the same thing. I decided to use the dark colored ones for the landing/entry and keep the light colors for the interior of the oven. I made a couple of different trips to pick them up and all of the pallets I saw had similar variety of shades. There must be some variation in the colors of the raw materials they use to make the bricks.

Nice work on getting the gradient in the arch - looking good.

Aside from appearances, do you also agree with me that the darker bricks are notably harder and perhaps imperceptibly heavier? I'm curious if they actually have different thermal characteristics (presumably higher heat capacity, hence longer heat up time but also longer heat retention).