39" Stargate Pompeii

[Amac]

Re: 39" Stargate Pompeii

Row 8 complete - just 2 (or 1.5???) more and a plug. If the weather holds the next few days should close the top. Now its at the "pantheon" stage

[deejayoh]

Re: 39" Stargate Pompeii

Looks great! nice work on keeping those courses even and symetrical. I've got the the first course laid out, but the dome is still very much a concept in sketchup at this point!

I was surprised how easily those bricks cut, however.

[Amac]

Re: 39" Stargate Pompeii

Thanks DJO
One thing I would do differently. I cut the bricks in half for the first courses a little less than 5" on the outside and a lttle more than 4" on the inside. I just guessed this but my guess was just a bit out! It works but every now and then I had to reverse one of the bricks, or shave some more off the back.
Get this measurement right and it will do for the first 3 or 4 courses, and save you headaches. I thought also this angle would change as you went up the courses. It doesn't! If you are cutting half bricks it will remain the same. If you are cutting 1/3 bricks it will be closer to 90 degrees but won't change as you go up the rows.
Aidan

Aidan

[deejayoh]

Re: 39" Stargate Pompeii

Aidan -
thanks for the tip! I did something like that. I cut a piece of wood with a 5 degree angle and used that as a jig to cut each brick. 3 cuts per brick instead of one, but with the saw it went pretty quickly. I think it ends up with a piece that is 4.5 inches on the outside and 4 inches on the inside. Seems to leave a pretty small mortar gap, which is what I was looking for.

Dennis

[Amac]

Re: 39" Stargate Pompeii

I Just checked my wooden jig and yep 5 degrees (or 85) is just about dead on it would vary a little depending on the oven size. I should have copped it earlier but wasn't paying attention, and went ahead and cut the first row.
Eventually I got it (almost) right

[Amac]

Re: 39" Stargate Pompeii

Since wednesday (interrupted by rain on Thursday - Friday was a bit better) I got row 9 and 9.5 done (I had to cut this row to allow room for a plug). I hope I didn't cut too much as my plug will be a bit more than 3" at the outside.
I am trying to decide whether to join two partial bricks (horizontally) to make the capstone and have a tight seam on the outside - or just leave a similar width seam as everywhere else and use a single piece.
Another option would be to rip out that cut row and do it again - but cutting it was a PITB. Any recommendations?
I used yet another of jcg31s ideas - platform attachments to the IT - for the last two courses. It worked out OK although I didn't cut the bigger one big enough and it was hard to steady. Also the weight of the bricks made it impossible to turn the wingnut underneath - but I was able to slide out the plastic piece on the floor supporting the IT centre, to loosen it.
Aidan

[kpms1st]

Re: 39" Stargate Pompeii

Hi Amac
looking good I ended up with a plug that I had to shape like a pencil point which was only slightly dangerous fingers that near to angle grinder blade not to be recomended,some where on forum Ive seen the plug done in 2 halves for a tight fit so maybe thats the way to go.Am still in process of sealing outer brick dome got some sika water repel but could not get detail on life span for recover then found they make a water seal product that has 10 year life also is breathable so waiting for that.In answer to your question on construct its the basic dome with a layer of 25mm ceramic over the hole dome with another 25 over top half then vermiculite mix plastered over to reshape to a semi smooth dome then as my base was tighter than originaly planed had to compromise and quarter my outer brick shell and lay them on top by the way second dome much easyer to put up not to many fall in how ever my insulation layer is not as thick as would have liked only have 25mm c.b then 50mm vermic at base but it does work and holds heat reasonably well.enjoy your first small fire soon.
kpm

[Amac]

Re: 39" Stargate Pompeii

kpm
thanks - the plug hole looks rounder on the photos than it actually is - I have a cardboard template of the inside and maybe today will do the rest and get the plug done. Weather seems Ok. Yesterday was a bit of a lost day as I went to the U20s match Fri and a few pints, and then watched the match yesterday.

had to compromise and quarter my outer brick shell

Ah - I get it - I thought those were still the firebricks. I was a bit surprised how well they matched the rest of the structure.
Do you use an infrared thermometer or have you fitted thermocouples?

[kpms1st]

Re: 39" Stargate Pompeii

Hi Amac
At moment Im using a digital cooking temp gauge which only goes to 200c so Im going on the colour of the dome figure its up to 700f when it clears of soot ,but intend to get an infared one soon malpins have them & they go from -40c to 500c but their looking for 85? so will look on internet .Price of bread has droped by 60% so oven might even pay for its self yet
all the best with dome kpm

[Amac]

Re: 39" Stargate Pompeii

Well almost exactly 4 weeks to the day (13th Feb) I laid the first bricks - the arch - and today with no fanfare at all- I closed the dome. Have to say even though it is nowhere like as well cut and built as many of the domes on here I really like it. I know how Michaelangelo felt when he finished the dome on St Peters, except there was probably a crowd of hangers on around
If it wasn't for the encouragement from members on the forum I would still be looking at a pile of bricks - now it is a dome and a pile of brickdust and a smaller pile of bricks.
I decide to go for a two piece plug similar to one I saw on here - but I can not for the life of me remember whose - probably more than one.
Still a lot of cleaning and grouting to do on the inside - the sexy bit is over, now the hard slog. I hope I can maintain the enthusiasm
I measured the interior height and it is just tiny bit over 20 1/4" so I managed to reel it in (from 21") by almost 3/4" since the arch was cleared. With a small bit more effort this could have been at least an inch.

[deejayoh]

Re: 39" Stargate Pompeii

Very nicely done! Looks great. The other two-layer plug I have seen that is like yours is on Ken Wiley's "Kentucky Dome"

You got that dome up very quickly. I think we started our threads about the same time and I haven't set a single brick into mortar

call me jealous!

[Amac]

Re: 39" Stargate Pompeii

Thanks DJO - it looks good to me anyway - I just hope not too many of those master builders on here look too closely

I haven't set a single brick into mortar

As I said on your thread the way you have cut those bricks looks like you will hardly need any mortar.

I thought I ordered enough bricks for a 36" but I still have about 40 left after the 39" dome. That ought to be enough to finish the vent and landing? I guess it is because I used 3" bricks.

I thought about trying for what they call a thermal break like Giannis, but I'm getting lazy again so I think I will skip that.

The outer arch will be the same semicircle shape 12" radius lifted 1.5". That gives 1.5" all around to allow for a door. Will that be enough? Too much?

[deejayoh]

Re: 39" Stargate Pompeii

On the reveal, I am planning a 1" around the door. I think 1.5" may be a lot. But I think it depends on your landing design. If you are going with the flared landing, then 1" reveal is probably the way to go. If you are not going to flare the opening, then maybe you would want a wider reveal, just to give yourself the extra room?

FWIW, with all the cutting I am doing - I suspect I will use a lot more bricks than you. I started with 200. I think I've used about 85-90 so far and I am not into the dome. I think each tier uses 13 bricks - obviously declining as I go up. I should do that math...

[Amac]

Re: 39" Stargate Pompeii

No - no flaring - it looks good and is probably very good for working with but too much precision for me.

I suspect I will use a lot more bricks than you

You probably also have 2.5 inch bricks which add a couple of more rows. After the soldier course I had 9 and 1/2 plus the plug.

I should do that math...

Don't ask me to do it anyway - I got an F for my latest effort on one of Giannis threads

[GianniFocaccia]

Re: 39" Stargate Pompeii

Looking really good, Aidan! I too, am jealous of the speed at which you completed your dome. You will no doubt spend many hours enjoying the fruits of your labor, all done miraculously with a hand-grinder. Regarding a thermal break, given your climate, you may want to reconsider skipping this element. Sure, its a little more work, but you only get to do it once.

John