39" Stargate Pompeii

[Gulf]

Try an old window screen. If your careful you can clean it up and put it back in the window before she finds out that it is missing

Here is one way.

[GianniFocaccia]

According to tscarborough, the ideal mortar has a variety of aggregate sizes in it, much like the jar with multiple sizes of rocks, pebbles, sand, etc. This keeps the portland to a minimum, and if the aggregate is small chunks of firebrick, even better.

[Amac]

Originally Posted by Gulf

Try an old window screen. If your careful you can clean it up and put it back in the window before she finds out that it is missing

Luckily we don't really need window screens here. I guess we don't get a lot of balmy evenings with tropical insects etc. zooming about, and our mosquito population is virtually non-existent. I was tempted by some kitchen utensils but thought better of it and bought a sieve (with a few different grade inserts) for a few quid instead
that brickdust looks good. Mine is all over the place though because of the grinder.

Gianni

According to tscarborough, the ideal mortar has a variety of aggregate sizes in it, much like the jar with multiple sizes of rocks, pebbles, sand, etc. This keeps the portland to a minimum, and if the aggregate is small chunks of firebrick, even better.

This stuff will work with larger joints Ok I suppose - but the smaller and variable widths I will need something finer. I guess I can make two mixes at once

thanks for the feedback - really appreciate it
Aidan

[Neil2]

"I guess I can make two mixes at once"

This is what I do. Two mixes, one for the narrow part of the joints and one for the wider parts. This also minimizes cracking.

[Amac]

During some breaks in the rain I managed to get the arch built. I think it is best to start with the arch. The dome should fit to it unless something goes seriously wrong as I was able to use the IT as a guide for the arch by turning the head slightly - up to a 1/4 turn in each direction which is negligible difference to the radius used for the rest of the dome construction. I did mix two batches and that worked out Ok. I had to make the mix wetter tham I expected.
Mu keystone looks a little dinky. I had to slice my last brick in two, The mortar joints were a bit thicker than I expected.

Heres a few pics - front, rear, and top view (which show up my bad cuts. Then I had to cover for rain. We are lucky with weather though. Even Rome is covered in snow. Rugby was cancelled in Paris as pitch was frozen.
I laid a few of the soldier course later.

BTW when I was cutting a few extra arch bricks I realised (too late for this oven) I could have done with much fewer cuts. I cut each brick for the arch with 3 cuts. With the new method I could have cut two arch bricks with just three cuts - and reduced wastage.

Thers's a free pizza (by stargate delivery) for the first correct answer to that puzzle Solution will be posted at the end of the build.
Amac

[Amac]

Weather is holding up nicely, just a bit cloudy and about 7 or 8 C so I finished the 1/2 brick soldier course. I wouldn't like to do anything more than a 1/2 brick - those side joints are awkward. Also started on course 1 of the dome proper. This is where both the 10.5" arch and 39" dome begin - 1.5" above the floor.. I added the clamp attachment to the IT, having removed the arch "block" from it. So far so good and nothing unexpected.

No takers on my "arch cut" puzzle? - so I have include a pic of how I did the three cuts for the existing arch. A clue is that the new cuts will result in a slighly bigger arch brick that would still fit my dome and arch perfectly with no change to the arch radius

[GianniFocaccia]

Ah, shucks Aidan! I thought you meant two cuts for two arch bricks! I really wanted that pizza! My bad!
John

[Amac]

Good try Gianni - I guess I should have said "straight cuts". I would have killed myself trying to cut those with the kickback from my cutter

Also the horizontal line only looks like it is at the centre of the bricks. In reality the arch brick extends slightly past halfway. The solution is on the back of the brick.

[Sharkey]

Good to see you making progress Aidan. I've been waiting to see how your arch-dome transition turns out.

You could have got 2 arch bricks out of a single brick with the 3 cuts in my attachment - green cut first. The angles are slightly different but it would probably still work.

Keep up the good work.

[Amac]

perfect Sharkey - what's your favourite topping?
It would have saved me (and my blade) some work and I did want to have a slightly thicker opening, It narrows to around 3 1/4" at the opening. Just let me flip the brick. There - I actually drew that using the same wooden jig which I used to cut the arch bricks - just slid it towards the middle.

The two non 90 degree angles are a function of the dome/arch combination. In mine they work out at 135 and 145 degrees to make up the 540 degrees of the pentagon. Of course there is no need to work out all those angles. They will just happen once you draw it out as I have shown in the second pic. Better to do it on a full scale.

BTW there was something you had said back on Aceves thread - that the IT would no longer grip the bricks if I change the radius towards the top of the dome. After thinking a bit more on it I think it should work as normal. Just the rows will tilt in a bit more.

Good to see you making progress Aidan. I've been waiting to see how your arch-dome transition turns out.

Well other than bad or careless workmanship (and I've already had my share of that) - I can't see how it can go wrong, and it should, if my theory is correct, follow the internal curve of the dome naturally - without any "reaching"

Btw I am awaiting activity on the "rock and hard place" thread. How is it going?