Central Utah 42" Pompei Build (continued)

[paynerob]

I will soon be updating the progress of my oven build. Lots has happened since my last post. However, I thought I should start a new thread since I originally posted in the wrong area. For pics and posts on my build up to the beginning of the dome, see here: http://www.fornobravo.com/forum/f14/...tah-20832.html. More to come.

[paynerob]

Re: Central Utah 42" Pompei Build (continued)

During the month off from our oven build, I had to figure out the bevel for the back of my arch. Using my indispensable tool, I traced out the curve of the dome on paper. I then drew in the profile of my arch. Based upon the drawing, I determined that my fifth course of bricks would rest on the top of my arch. I could then determine the perfect bevel for the back side of my arch bricks. Based upon the drawing, I created a pattern and cut each brick of my arch accordingly. Here's my drawing and brick pattern.

[paynerob]

Re: Central Utah 42" Pompei Build (continued)

The weekend of July 20th, my oven build continued. We hauled to our cabin a supply of medium duty firebricks and Fire Rock High Temperature Mortar sourced locally from Interstate Brick. Both worked great for this build. We measured, cut and cemented the arch pillars (24 bricks). We then cemented in the soldier course (40 half bricks) and the second chain of bricks laid on their side (22 half bricks). To save mortar and add some stability we cemented beneath each brick in the second and subsequent chains a wedge of firebrick. My indispensable tool worked great!

[ATTACH][ATTACH][ATTACH][/ATTACH][/ATTACH][/ATTACH]

[paynerob]

Re: Central Utah 42" Pompei Build (continued)

During the weekend of the 20th, we continued our build. We cemented in the inner arch bricks, the 3rd chain (23 half bricks) and the 4th chain (25 half bricks). For chains 3 to 7, we used half bricks cut on a five degree angle on each side to create a smaller and more uniform joint between bricks. We were careful to offset the joints from chain to chain which periodically required cutting and installing smaller bricks to keep seems offset. To support each brick, we cut stakes and screwed them into the wood floor template. I didn't see this support method from previous blogs but it worked great. I highly recommend it.

[paynerob]

Re: Central Utah 42" Pompei Build (continued)

The July 24th weekend gave us four days to finish the dome build. The fifth (26 half bricks) and sixth chains (28 half bricks) continued with full half bricks cut on an angle. The sixth chain fit perfectly over the top of the arch. The stick support system continued to work great.

[boerwarrior]

Re: Central Utah 42" Pompei Build (continued)

Looking great!! That's quite an arrangement of wood to hold your firebrick while drying - very artistic!

Nice house too, by the way! Keep the pictures coming!

Neil

[paynerob]

Re: Central Utah 42" Pompei Build (continued)

The end of day 1 of the 24th weekend brought with it the realization that I had grossly underestimated the number of bricks needed for the weekend. So, it was off to Salt Lake for another load of bricks and cement (4 hours home, a night over in SLC, early to the brick company, and 4 hours back to Central Utah), ugh!

Day 2 was chains seven (24 half bricks), eight (23 half bricks), and nine (20 half bricks). In the eighth course, we began to narrow the width of our bricks. Courses 8 and 9 had an exterior brick width of 4". We continued to taper the bricks inward by 5 degrees on each side.

[paynerob]

Re: Central Utah 42" Pompei Build (continued)

The third day of our weekend presented the challenge of a very steep brick slope. As you can tell from the first two photos below, the stick supports for the 9th chain were also very steep. We attempted one last chain using the sticks. It seemed to be working for about 3/4th of a row when the sticks shifted and the bricks went crashing to the center of the floor. So much for the sticks.

For the remainder of the dome we shifted our support system to a plywood disk and mound of fire clay. The circumference of the dome opening at the 9th chain was approximately 18 inches. We cut a 19" circle of plywood and supported it from below with our leftover sticks. We then created a pile of fireclay in the dome opening and compacted and smoothed the clay with a curved scrap of plywood leftover from cut-out of our central floor template. We misted the fireclay regularly so that it retained its shape for the final chains of the dome. This support system worked great and was easy to do.

[paynerob]

Re: Central Utah 42" Pompei Build (continued)

Onward to the 10th (18 half bricks), 11th (12 quarter bricks) and 12th (5 quarter bricks and 5 triangular wedges) chains. For the 10th chain, we used bricks with and outside width of 3.5". The 11th chain bricks had outside widths of 2". The 12th chain required a combination of quarter bricks with outside edges of 2" and triangular wedges. It was a bit of a challenge to taper the triangular wedges to fit neatly in the confined space. Check out pictures in a later post to see what the 12th chain looks like from below.

[paynerob]

Re: Central Utah 42" Pompei Build (continued)

Finishing off the third day of our weekend was the keystone. We had hoped for a single keystone but the dimensions didn't quite work. So, the keystone would be comprised of a two triangular wedges. As with the 12th chain it would take several trips back and forth between the brick saw to get these wedges tapered just right. Finally we were there, butter them up, and tap them in. Hurray for the completed dome!

[paynerob]

Re: Central Utah 42" Pompei Build (continued)

On the final day of our weekend, we pulled out the dorm form, slid it out the front door and then took a few pictures around the dome.

In the picture of the top of the dome, you can see the combination of bricks and wedges in the 12th and 13th chains.. As I re-review this pictures, I notice that in the 11th chain we also had a combination of bricks and triangular wedges--similar to the 12th but mostly just filler for the wider gaps.

The photo out the door also reminds me that we had to piece in several small bricks along the inside of the arch to finish off the connection of the chains to the inner arch. We used the sticks to hold these pieces into place while the mortar dried. At some point during the weekend, I took a hand grinder to the the area and ground down the rough edges.

[paynerob]

Re: Central Utah 42" Pompei Build (continued)

Now for a little clean up scraping of errant mortar, filling gaps, sponging off the bricks, and saying goodbye to the floor template. Couldn't have been happier about how this template worked with my indispensable tool!

[paynerob]

Re: Central Utah 42" Pompei Build (continued)

And, for our final task of the July 24th weekend, we build the exterior arch. It took a little thought to figure out how to line up with the outside pillars which are approximately 1.5" wider than at the inner arch as a result of the door reveal. In the end, the same angles for the bricks (as the inner arch) work great. Each brick must be cut approximately 3/4" shorter to keep the inner and outer arches level. It also takes two extra cut bricks (14 total) for the outer arch. We used the same 3" depth for the outer arch as the inner which makes cutting on the brick saw a breeze.

All in all an extremely productive 4 day weekend! Now on to the vent.

[paynerob]

Re: Central Utah 42" Pompei Build (continued)

And then nearly a month passes to accommodate some summer vacations. In the meantime, I figure out exactly how this vent will work. The space between my arches is approximately 8.25". I need a rough opening of 8" square to accommodate my Duravent anchor plate. I plan on two layers of brick for the vent, plus wedges to support over the top of the arch. I also need to set my vent back 1/2" from the outside of the outer arch to provide a backdrop for my hardibacker rough exterior (will make more sense later). I want all of my joints to overlap for strength. See the photo of my plans.

Now to find time to build the vent. The trouble is that the vent must be set and dried before we can continue with the chimney and outer structure. The next available weekend affording a chunk of time is not until mid-September and something seems to be happening every weekend before then. So, I squeeze out a quick Saturday trip to the cabin. Up at 6 a.m., travel to the cabin, building the vent from 10 a.m. until 3:00 p.m. and four hours back to the SLC.

The build of the vent itself works perfectly. The two layers of brick take 5 bricks each (total of 10 bricks). I enclose the outsides of the arch with 8 split bricks each cut approximately 3" wide (9"x1.25"x 3"). There is a bit of funky piecing at the top of each side but all goes swimmingly. When I am done, I eek out the last little bit of mortar from my seventh and final bag of Fire Rock mortar. In the end, I don't have a tablespoon of mortar left over but have had just enough to finish the job! Whew!

[paynerob]

Re: Central Utah 42" Pompei Build (continued)

A few more pics of the finished vent. And then, the agony of waiting another month to continue.