Oregon 42" Pompeii Oven

[Ope-dog]

Hi Corsairmo. What a great looking oven!!! While we started our builds about the same time, you apparently stayed much more motivated that I during the winter! lol. I'm in Hillsboro, OR.. however my build is taking place at my property in PeEll (just west of Raymond on the Chehalis River..) so time never seems to be my friend, lately.

Having just insulated my dome and put on a p/v-crete rendering, I was very dismayed to see my perfect sphere go by the wayside and now it looks like a huge dinosaur turd sitting atop a cement counter. LOL. I'm really going to have to work some magic with my final rendor to try and recapture the dome shape.

I am curious to know how your oven fared through it's first sets of fires. I'm itching to get curing fires going now, and since a large portion of my mortar has been allowed to cure for several months now, I'm hoping the moisture drives out sooner than later. But being in the NW.. does it ever REALLY dry out? I had to modify my dimensions quite a bit at the start and redesign my arch on the fly.. your arch came out great!!! Would love to see more pics and hear of the progress!

Scott

[SableSprings]

Hello. Great job!
I would like to build a corner one similar size to yours (40 or 42). Would you mind sharing dimensions for the stand and for the oven, please

You can find most of that information in my build thread (link in the signature line at the bottom of any of my posts). If you can't find what you need there, a little more detailed question of what you need would be appreciated.

[gvegasg]

Hello. Great job!
I would like to build a corner one similar size to yours (40 or 42). Would you mind sharing dimensions for the stand and for the oven, please

[SableSprings]

Dome looks great Corsairmo! As Mark noted above, we do recommend insulating before starting the curing fires...but going slow as you are doing is perfect. Once bricks are wet, it takes a long time to force out the water. Once the moisture stops "pouring" out during your long, low temp fires, you might consider laying your insulation to keep oven brick temp more even. With a set oven you are wise to go slower than the posted time/temp schedule. You might even think about using briquettes rather than wood simply because you can control the long & slow early curing temps more easily. Good job monitoring & moving your fire around to make the heating more even.

[MarkJerling]

I thought I had read that the advice is to insulate before firing to help prevent cracking.Careful!

Your completed dome looks lovely.

[Corsairmo]

The oven is finally enclosed!



And I think the inside is satisfactory. I used a plywood disk to support the bricks as I laid them. But once they were set I lowered it down (via the car jack I used) and was able to test the hold and clean up the inside as well. I have been using a chicken heat lamp to start to cure the oven which i left on for about 3 days. No outside insulation yet as I simply haven't had time, but I'm trying to keep it well insulated from the rain until I can finish it off.


The heat lamp didn't really make a difference, the floor stayed stone cold and the dome was at best room temperature. So I've moved on to a small fire. I'm going extra slow because the bricks and the oven work have been soaked with rain, before and during construction. Even with the small fire, the wetness of the air venting out the top of the arch is amazing! It's a constant stream of moisture coming from the oven. For those who have an InstantPot it reminded me of venting the steam and sticking my hand into it! I'm on to day two of fires and I am trying to keep the small fire going for about 2-3 hours and I'm checking and dampening it as needed with my old wooden arch form. I've been reloading the fire and moving it around every so often to avoid hot spots. I don't have an IR thermometer, yet, but so far the dome inside ceiling is a modest warm to slightly hot to the touch, the exterior is cold and the floor is room temperature to the touch unless directly after I have moved the fire off of it. I think I'll keep the small fires up until it stops pouring moisture from the dome. There are some moist exterior mortar seams that are visible from time to time if the fire has been in that area for a while, but so far no cracking of any kind! Fingers crossed!

[Corsairmo]

Courses are closing in! I'm still sagging a bit on the arch side, but I have to say I'm pleased with how round the rest of the oven is turning out, seeing as I took out my IT for this last course. They are dead ugly on the outside but from the inside it looks quite good! I actually already laid the course onto the plywood circle, but forgot to snap a shot before I covered it with a tarp to keep the rain off. I'm now using 1/4 bricks for the course and I think I will have 2 more before I seal it up with a keystone!

[MarkJerling]

Thanks Mark! It feels crude compared to others but it's solid and I'm so excited to put it to use all the same!

If you think your's is crude, then you've not seen mine! LOL

[Corsairmo]

That's coming along nicely!

Thanks Mark! It feels crude compared to others but it's solid and I'm so excited to put it to use all the same!

[MarkJerling]

That's coming along nicely!

[Corsairmo]

I've been working on the oven throughout the week and feel pretty happy with how things are turning out. Tying the dome into the arch has been as tricky as I thought it might be. I didn't do myself any favors by using only half bricks for the arch. I had considered using longer 6" lengths but was loathe to "waste" the bricks when I thought I might run tight on bricks. I ordered 220 and needn't have worried, I will have plenty left over but have had to work harder than I should have to make the dome and arch blend! The arch is tying in well enough I'm not worried about collapse or such, but it would have been easier if I had just another two inches of arch depth to rest the dome bricks on. There is a dip that I am slowly compensating for with each successive brick course.

I feel foolish, in my pursuit of shaping a perfect keystone to tie the 7th course together I neglected to cut the depth of the keystone down to match the bricks around it since it was handy for griping it as I test fitted the piece, so it sticks out almost an inch! I realized my error after struggling to get it all set just so and I said, "Screw it! I'll just use the angle grinder to lop the excess off!" So that's why there is a slightly off-center 1/4 brick keystone sticking out above the archway.

I think I am about at the stage where I will move on to smaller bricks as the triangular horizontal gaps at the base of my brick courses are getting significant. For my 8th course I did taper the bricks with the saw so that they fit bit tighter, but I am debating whether it is better to do that again for the next course or move on to 1/4 bricks.

All in all I am happy, things are working out quite well. I am using a table-saw type tile saw, which presents significant limitations to my ability to taper my bricks. I really can't justify spending on a better tool, but for a first oven (there might be more for others, this has been a great deal of fun and friends are already asking about it) I am happy enough with the results. Next time though, I will be aiming for a finely fitted bevel-cut oven! Kudos to all those who put in the extra time and effort for the works of art they are!

[MarkJerling]

Finished the archway today, I'm quite pleased with it despite my limitations in masonry!

What limitations? LOL That looks fantastic! Well done!

[Corsairmo]

Finished the archway today, I'm quite pleased with it despite my limitations in masonry!

[Corsairmo]

I put in some night work to finish the fourth course. Night arrives promptly at 5:30pm these days so it was in with the work lamp and the added help of the beautiful full moon! I haven't mortared in the arch bricks after discovering that I need to tweak the fit a bit, but I don't think the neighbors would appreciate the tile saw noise at almost 9pm at night! So the tweaks and reinstallation will have to wait till another night! So far so good! I've recruited two capable mortar mixers who love to dry batch and prep my mortar (about a half gallon at a time) which is fun for them and helpful to me. Crushing up brick chips with a hammer is also a fun chore for the 5 year old! Many have said that they regret not building their ovens sooner, but as a busy dad of four, I think the reason many might wait is that its hard to give the needed attention to detail earlier! My cuts aren't perfect and just by cutting the edges of the floor circumference bricks I realized I would be best served abandoning miter cuts for each brick of the dome. Four courses in and I'm not regretting the choice, even if the masonry work is much less pretty than other's works of art. My edges are lining up true and my courses are angling in at a steady rate each course.

Interesting observation regarding the brick quality. It seems that the crumbly edges are a manufacturing problem, not a brick composition issue. The cut corners are durable and true, and when shaping brick cuts I can apply a great deal of scraping force with my trowel or other tools before the brick deforms, while the manufactured edges are often easily damaged, either preexisting, or after things like a scrape of the mortar trowel or a tap of my rubber mallet. I've taken to laying my bricks on their side, so at least one edge is square and true! Has anyone else run into this issue?

[Corsairmo]

It is really important that the bracket is at 90 degree or perpendicular to the center of the dome. Equally important is the center of the rod at the halfway point on the brick. The errors are cumulative as you move up in courses, then all of a sudden everything is out of wack and hard to correct. You really need to take care of this right off the bat. I would at least ditch the 2 x10s.

I'm not sure I capture the importance of how high my platform is for my IT. It seems to me that the height of the dome is fairly arbitrary, for example if one were to add a soldier course to their dome, the curve is thusly affected compared to one who has not added that vertical height. It seems that, within reason, the starting height is inconsequential as long as consistency of measurement is maintained. Also, I have a close up of the IT pivot (screw) as I think you'll see it's about as reasonably centered as one can make, or as centered as I've seen from most any other IT? In any case things seem to be proceeding smoothly and I'm not sure I'm capturing the compounding error element but I appreciate the assessment and information!