36" in Seattle

[ThisOldGarageNJ]

Re: 36" in Seattle

peanut butter smooth no chunks

Are you mixing by hand, Try a 5 gal bucket with a drill and a paddle mixer

cheers
Mark

[kebwi]

Re: 36" in Seattle

Yeah, I've seen those online, and I admit that mixing it up was disappointingly difficult with a stick. I'll look into it.

Thanks for the tip.

[jmhepworth]

Re: 36" in Seattle

I tried mixing mortar in a bucket. Without a power tool, it's just too hard. I bought a mortar mixing tray from HD and mix it with either a hoe or for smaller amounts with the trowel. I was much happier after I stopped trying to mix mortar in a bucket.

[ThisOldGarageNJ]

Re: 36" in Seattle

keb...- Harbor Freight Tools - Quality Tools at the Lowest Prices when i was mixing my mortar i used this on my dewalt 18v drill,, for small batched it works fine

Mark

[Les]

Re: 36" in Seattle

keb...- Harbor Freight Tools - Quality Tools at the Lowest Prices when i was mixing my mortar i used this on my dewalt 18v drill,, for small batched it works fine

Mark

Ditto - simplifies the task a LOT!

[kebwi]

Re: 36" in Seattle

Yep, I wanted that along time ago for concrete but my local HF didn't have it (or I didn't find it). HD and Lowes sell the same thing (for $13 instead of for $4) I'll have to consider another trip, although they're far enough away that is isn't worth it unless I get a few things per shot. I'll have to consider my shopping list first.

Thanks BTW.

[ThisOldGarageNJ]

Re: 36" in Seattle

home depot or lowes should have a similar one in the drywall department near the bags of mud... (joint compound) they use them for mixing the mud...

Your definitely welcome
Mark

[kebwi]

Re: 36" in Seattle

Finished the floor, mortared the first course (except where the course meets the entryway on one side), finished the second course (except the eventual arch merges), started the third course. I soaked each brick that was about to be added and thoroughly sponge-brushed the adjoining faces of the already-placed brick that was about to be bonded to. Seemed to work for the most part.

If you look closely, you will notice that my first three courses (all vertical side walls with no dome-curve) consist of right-trapezoids instead of isosceles trapezoids (credit to Lars for the seemingly obvious idea which I admit never occurred to me). I can produce two oven bricks from as single fire brick with a single cut this way. Isosceles trapezoids would require three cuts.

Other than chronic curiosity about variations of the mortar recipe and apprehension about the mortar to water mixture/consistency, I feel that everything went pretty well.

I used 6:4:2:1 (Lars') for absolutely no particular reason. I haven't tried anything else (including the Pompeii 3:1:1:1) because I wouldn't have the first clue what to look for when weighing variations against one another. I would love to commit to a recipe so I can mix up large infrequent dry batches instead of small frequent batches.

I used 4 1/2 parts water. 4 seemed too dry and 5 seemed too runny, but maybe I'm wrong. Maybe 4 looked just right or maybe 5 looked just right and I simply didn't realize it. I just really don't know.

Anyway, I feel really good about getting some bricks in place and starting the vertical assent. I will have to make the inner arch next of course. Vertical work is done (except for completing the third course shown in the picture) until I get the inner arch in place.

[ThisOldGarageNJ]

Re: 36" in Seattle

nice,, keep going

[kebwi]

Re: 36" in Seattle

Parged one side of my hearth, a highly nonvisible side, experimentally, at 3:1 sand/portland. I'll let it set good and solid, assess it, then decide what to do about the more visible sides of the hearth and the foundation.

Finished mortaring the first course (at floor level in my design) to the entryway arch-support bricks. This required the brick in the first photo, amongst my fancier cuts so far. The floor had some fancy cuts in it too (see earlier photos).

Built a form for the inner arch: two layers of masonite with 2x4 chunks in between and a thin strip wrapped over the edge (strip not shown in the first picture, but visible in that later picture).

You will notice in the third picture that I have cut a 45-degree edge off the inside edge of my inner-most arch (a cinch with the 45-degree guide that comes with the HF saw). This should serve two purposes: one, to facilitate better airflow and let smoke escape more easily, and two, to provide a slightly wider angle of access to the oven.

Mortared up most of the inner-inner arch (my inner arch consists of two arches, I really need to post some updated CAD designs). The last brick was going to be really tight, probably pushing the other bricks out of the way, so I decided to just rest it in its place to hold the arch together. I'll shave it and mortar it in place in a day or two, no need to rush it.

I used 3:2:1:1. I arrived at this not as a variant of 3:1:1:1, but rather by starting with Lars' 3:2:1:1/2 and then deciding that a little more lime might make it creamier...which I guess maybe it does, I don't really know, but that's what I decided. So, any feedback or thoughts on that are welcome. Basically, what I've got is a mortar that has more fireclay than the Pompeii/FB mortar. If anyone can speculate what effect more fireclay would have, I'd love to hear it.

A point of concern: If a mortar joint breaks due to a bump after it has become mildly solid (is this what "setting" refers to?) after a few minutes (or after a few hours in some cases), I have little choice but to push the bricks back together and hope for the best. However, the mortar is often dry enough at this point (even after a few minutes) that the crack remains quite obvious, which suggests to me that the bond has not been reestablished. When this occurs (minutes, hours?) is the joint basically ruined forever. Is that particular brick-brick bond pretty much a lost cause from then on? It kind of seems that way upon visible inspection. Of course, I'm not going to purposefully test it later to see how well it holds, so I will never really know whether such bonds are considerably weaker than bonds that don't break. Thoughts?

[KINGRIUS]

Re: 36" in Seattle

Thought- I have had a few of those visible crack scenarios and it appears to me that the bond with the neighboring brick is not completely broken but just partially broken. I have one of those cracks in my entry arch but the brick doesn't budge. I think as long as long as the mortar is still moist and it is bumped it will still seal, even if you see a crack. Just my input.

By the way your cuts look very nice. So far so good!

Darius

[kebwi]

Re: 36" in Seattle

Just cutting bricks, waiting for the weekend. I can't do much mortaring during the week. The brick shot shows, in the background, some long-ways tapered bricks that will comprise the outer arch. They were trimmed to 3.5" wide first, so as to fit under the saw. On the end, next to the long tapered outer arch bricks, is the last brick of the inner-inner arch (my inner arch will have two layers). I couldn't mortar it with the rest of the arch because it was too tight. Had to give it a shave first. The numerous wedges in the foreground will form a transition from the vertical sidewall to the first dome course.

The second shot shows my inner arch (on the left) being kept warm under the tarps with a halogen. It has been dipping into the low forties, possibly the high thirties, at night. Although it is highly unlikely, I don't want to risk a freeze on fresh mortar.

Cheers!

[kebwi]

Re: 36" in Seattle

Almost finished the outer-inner arch (minus the keystone which was too tight: mortar gaps were too large, placement didn't perfectly conform to the protractor...I had to shave the keystone, which I haven't placed yet).

Note that the inner-inner arch, which lies just behind the outer-inner arch (visible in the photos attached) did not form a mortar bond between the feet and the bricks that line the entryway, although the bricks comprising the arch itself seem to have bonded to one another. Consequently, that arch could easily rock or tilt up on its feet with the slightest push. Hopefully the construction of the second layer will solidify things significantly.

This two-layer arch forms the inner arch, i.e., that arch behind the vent against which the dome merges. The outer arch will continue from where the inner arch leaves off to the front of the oven, indicated by the floor bricks. It will obviously have a vent opening as opposed to being closed off like the inner arch.

Added most of the wedges that will transition from the vertical side-walls to the first curved dome course. Also made my trickiest cuts yet, transitions from the wall to the arch. They are not merely straight notch cuts. Rather, one side of the notch is actually tilted w.r.t. the axes of the brick, so as to slope up the side of the arch. Overkill? Yeah, I think so.

Also finished building my dome-brick placement tool ("indispensable tool" as FB colloquially calls it), described in the next post.

[kebwi]

Re: 36" in Seattle

Here is my brick placement tool, or as FB calls it, the indispensable tool, designed and manufactured to approximately 1/16" precision...give or take . It is a little more complicated than some other designs I've seen. My design enables full control over the brick orientation on a per-course basis by providing adjustment of the following parameters:

• the distance from the center (of the floor) to the point of intersection between the brick radial axis and the floor
• the length along the radial axis from the floor to the brick.

These two adjustable parameters make it possible to construct a dome of any conceivable curvature while still maintaining perfect edge alignment between the upper edge of one course and the lower edge of the next course up the dome.

Notice that the representation of the floor strut in the diagram (shown magenta) is floating in the air above the oven floor. This accounts for the 3/4" plywood protecting the floor.

In addition, notice that my design does not currently include a hinge between the floor strut and the radial strut. Rather, the floor strut represents a stop against which the foot of the radial strut braces. This is an arbitrary design decision of course...and perhaps not the better of the two options since it will require me to keep the two pieces in alignment. I opted for this design in my first pass due to concern that a small hinge might not withstand the repeated stressful application to a full oven's worth of heavy bricks. However, if after beginning the dome portion of my build I decide that adjusting the two struts independently is too much of a hassle, I can always redesign with a hinge in mind...although it will require recalculating all parameters of the tool (floor-strut length for every course, radial arm length for every course, pin-hole positions along the floor strut, and pin-hole positions along the radial strut arms).

Cheers!

[kebwi]

Re: 36" in Seattle

Mortared the first merge between the vertical side walls (the dome in effect) and the inner arch (1st pic).

Mortared the keystone into the outer-inner arch, thus completing the inner arch (2nd pic)...although I have discovered upon removing the arch-form that there is vastly insufficient mortar between the two layers as viewed from inside the arch despite good appearances to the contrary along the outside edge. The crevices as viewed from the underside of the arch are distressingly deep. I intend to smear and push fresh mortar into the interior gap a.s.a.p.

Finished cutting the bricks for the outer arch and the second course wall-arch merge (3rd pic). I liked the look of the taper that I put on the inside of the inner arch (for functional reasons) so much that I put a similar taper on the outside of the outer arch bricks for purely aesthetic reasons. I think it will look very nice if the now completed inner arch is any indication (as vaguely suggested by the 2nd pic).

Also made the necessary calculations to alter my brick-placement tool to include a hinge between the floor strut and the lower arm of the radial strut. I hope to make the associated pieces tomorrow.

With any luck, if I get the bricks for the first curved course cut this week, I hope to begin mortaring the curved courses by next weekend...although I might build the outer arch first since the bricks are ready to go anyway.