Pdx 42" update

[Macrinehart]

Hi All - It's Saturday, what a day! Today I finished up the floor, decided to go with herringbone pattern and not regretting it. After spreading the sand/fire clay mix I decided to redo that work because the grain size was not fine enough. In order to get a better size I borrowed the fine siv from the kitchen, 2 mm square holes, and sifted all the pebbles out of my fire clay. Once that was done the notch trowel worked a lot better, and the floor went in easily as well.

I wrapped up the day by cutting all the perimeter bricks, and laying out the opening. The oven entrance is ever so slightly off center, but I think it's close enough that it will not be noticeable in the finished project. Overall I'm pretty satisfied with today's progress, but I think I will build the form for the opening before I finish.

[Macrinehart]

Ok, hopefully this hits the mark. I adjusted back to the Point suggested by mongota, at the center line that's 3-13/16" inch inside the dome. I marked the IR line on the block, moves the arch back a little shy of 2 inches from the prior placement.

[JRPizza]

Look back at post #34. You have a couple of inches of fore/aft placement where the TDC brick will intersect the dome. People that need to shorten up their landing as much as possible due to design constraints can move the arch towards the center, but that takes up some cooking space and leaves very little protrusion to build the chimney up/over. I moved mine forward/outward as much as I thought I could and still have a good inner radius on my TDC, as I wanted to have plenty of arch sticking out for my vent area. If you have room, I'd say move it out (away from center of dome) but not so much as what you are showing in your sketch.

[mongota]

Macrinehart
Mac, you're welcome. I noticed when I blew up the drawing that the drawing I marked up still has your dome opening at 10" tall. I recall you increasing that in previous posts. Still, using the drawing as a generic guide and adjusting the build to your current dimensions should help figuring the in/out range of the TDC brick and thus your arch. Build on!
Best, Mongo

[Macrinehart]

mongota - your markup of my drawing clarifies things a lot, thank you!

JRPizza - Iooked back at your post #23, which has the same CAD drawing #133 above. I didn't have all the same context back then, it makes more sense now. I do notice that in your build thread #3 your TDC brick is further forward than the updated drawing, it looks more loke Mongata's markup. From that I assume you advise positioning the opening arch even further inside the oven.

[JRPizza]

mongota has it right - your arch is a little too far forward. This is what I was trying to explain in post #19 and 20. I should have included the sketch below but I think it is in my build thread too.

[mongota]

It's possible I'm interpreting things incorrectly, but I'll post this and let you and the moderators chime on on this. I marked up your drawing.

I outlined the original location of your TDC brick in YELLOW. As I see it, if you locate it there you'll have to infill a small piece of brick behind the TDC brick, where the LIGHT BLUE cross-hatched area is, if you want to maintain the smooth spherical interior surface of the dome. I have seen builds where builders have left voids back there, but I didn't know if that was your intention.

By moving the TDC brick further back into the dome, outlined by the GREEN line, so the back edge of the brick touches the point shown by the BLUE arrow and BLUE text box, it eliminates the need for that cross-hatched infill piece.

You then cut your TDC brick as shown by the thin BLACK line.

If I buggered this up my apologies, the last thing I want to do is cast doubt in your head about your layout, as I remember myself how confusing it can be!

[Giovanni Rossi]

The perspective of your picture certainly exaggerates the depth of the landing. However, looking at your drawing, the flue is positioned further from the dome than I’ve seen in other builds. Certainly not an expert…just my 2 cents.

[UtahBeehiver]

David S actually mentioned the deep entry a few posts back. I deep entry does make if harder to access but your choice.

[Chach]

Your earlier pic of the troweled fireclay reminded me of a japanese zen garden.

Hahah me too

[Macrinehart]

Hi Mongo - you know it's funny, I think I have planned things correctly but you're comment has me second guessing myself, even though that positioning is based on the layout I had from my full sized template, reattached below. I could cut off up to 2" on the brick length. The chimney landing is on the outer rank of bricks. I am dispensing with the third rank (which is supposed to be the decorative arch). The chimney landing is outside the door. And the door will be an insulated door fabricated by my blacksmith friend.

[mongota]

One of those "I hate to ask a dumb question" questions, but I'll post it anyway.

Having a full brick length before the door reveal puts your oven door several inches (about a half-brick length) further away from the oven when compared to most builds. Are you planning an insulated door? If so, will the flue be outside of the door?

Your earlier pic of the troweled fireclay reminded me of a japanese zen garden.

[Macrinehart]

Thanks for the tips. I am using a 1/4" slotted trowel, that's about 1.2 cm.

Before setting the floor I wanted this quick preview of the oven opening. What I've got is a 20" wide opening with 2 ranks of bricks for the landing and a 1.25" offset on the outer rank for the door. Thinking of cutting the cal-sil off at the edge of the front rank, which will leave about 8.5" between the front edge of the heart and the oven landing.

Any final suggestions before I start laying the floor?

Cheers!

[NCMan]

Quick question - is the photo below about the amount of sand/fire brick clay needed for under the oven floor, or more? Disregard the existing bricks around the perimeter, they'll be removed. Thanks!

Looks good. You need just enough to be able to tap them down, w/a rubber mallet, just a bit, to get them all level and flat. You don't want to use any more than you have to. Also, if it hasn't been mentioned, what I did when first using the brick cutting jig, was to have some cheap soft red bricks to practice on, as I went along. Just a suggestion.

[david s]

Maybe about 1.2cm x floor surface area (in cm2) = volume in cm3 (divide this by 1000 to get litres)