New build - 1.2M dome

[UtahBeehiver]

I make it a point to visit wfo'ers when I travel so your build is on my hit list.

[jonv]

You would be most welcome

[jonv]

Somewhat amused to find that, even though I knew about 'the droop', expected to encounter the problem, and thought I knew how to avoid it, the droop has appeared on the sixth course. Despite my best efforts to set the bricks adjacent to the arch without losing height, I seem to have failed.

The next course will clear the arch. The dome remains fairly good in terms of roundness so I will just need to adjust the bricks passing over the arch to correct the droop. I found a laser line useful for getting these blocks in the correct position. I still have to cut some shims to pack up the bricks on each side of the arch, but I should be able to bring everything more or less level on this course.

[deejayoh]

That's nothing! I think I had to shim mine way more than that

[jonv]

Yeah, I'm not too bothered about it - just funny that I didn't manage to avoid it even though I was looking out for it... Shows up a bit better in this picture:

[jonv]

Droop? What droop?

I set the five bricks that span the arch, with some offcut wedges of brick underneath to correct the droop. I told the OH that clearing the arch is one of those big milestones in the build and we would celebrate once I get that far. I know I haven't finished the course yet, but there's a bottle of fizz on ice and I'm claiming it

Glad all the weird cuts are done for a while and it's a straight race to the keystone...

[jonv]

Finished the ninth course

This time I had to use smaller bricks; not thirds yet, but less than the half bricks I've been using on previous courses - a bit of wastage in cutting them, but I didn't want to drop straight to thirds. In retrospect, I may have been better changing to these on the previous course as the chords are a little more pronounced than I would have liked, but it's ok.

The mortar is still overcoming gravity - I just need to hold each brick for a while until it has grabbed hold. However, I am starting to experience some minor errors in the form now. Small errors in placing individual bricks have multiplied up a little at a time over the nine courses so that the rear of the oven is now a bit low and a bit tight on the radius; I am no longer quite flat nor entirely round.

Despite my best efforts to make small corrections on each course, I have not been able to address the drift. I think this is partly due to using arch bricks that are a close match to the dome radius; they do a good job of reducing the amount of mortar and they keep the form reasonable without having to worry too much, but they do somewhat limit the scope for making the small adjustments needed to bring things back on track. I have also found that some of the bricks are a little thicker than others - this might also have been part of the problem as I didn't notice until recently. I have even ground off a couple of them after the mortar has set...

I guess (or hope!) I'm not much more than 1/4 inch out at the moment but it is deteriorating as I near the top - just hoping it is still close enough when I get to cut the keystone... it will be most uncomfortable if I end up having to grind the thing to some funny profile once it has been stuck in there!

Anyway, another two weeks and the dome should be done

[jonv]

Shiny things

[Bauldy 2]

Wow looking good boss.ive also had to correct droop and tear drop shape.bauldy

[jonv]

Thanks

Good job these little errors only matter to the builders - the pizzas will taste just the same regardless

[jonv]

Getting a bit cold for this. Had to cover with thick old curtains and put a frost heater in the dome last night. One more frosty night and then we get a brief warm spell - hoping to finish before more cold weather arrives.

[Bauldy 2]

Looking good boss I've ordered stainless flu and a funnel shaped heat collector didn't want to double up on fire bricks and old stocks making chimney too heavy and bulky weather hear getting a bit nippy.I m also wrapping up oven at night are you going to do a design on plug? my daughter and partner designing a gecko for mine time to let her loose with the dremmel.Keep up the good work soon have a curing fire to warm u up.

[jonv]

Thanks The last few courses went a bit wonky - it's not as neat as yours, but I guess the pizza doesn't mind... I will fit the plug tomorrow, with the help of a skinny friend who can squeeze in there and mark out a template for it

I wasn't planning on a design for it, although I am thinking of one for the keystone of the decorative arch. I'll probably cut a large keystone from a piece of sandstone and carve the year and a design into it, if my skills will permit, or find a mason who does have the skills if I make a hash of it.

Look forward to seeing your chimney and funnel. Where did you find such a thing? I didn't see anything like that so went with a standard twin wall flue and anchor plate.

Cold enough this morning that when I soaked the bricks before cutting they came out with a layer of ice on them that I had to chip off. I suppose it kept the blade cool

[Bauldy 2]

Yep been very cold down here in Essex just above freezing all day used company called flu linings got a contact there they do different sizes to fit 6 7 8" funnels it's 316 grade 1 mm thick the flu is also 316 not as shiny as yours, I'd like to try and bend a stainless tube around flue pipe and run water through it to heat a hot tub or outside shower just need the pipe a small circulation pump some valves and then good to go

[jonv]

Interesting idea. Wonder if it will have much detrimental effect on the exhaust... Why not try malleable copper tube instead? Got to be much easier to bend around the pipe.