39" Stargate Pompeii

[deejayoh]

Re: 39" Stargate Pompeii

John -
yeah, my backyard project started last July - with a retaining wall, then pavers, and finally the coveted oven. I call it the $20k pizza oven and it's not really a joke...

I have been twisting my brain around this transition for weeks and finally think I know what I am going to do. We will see how it works when I get to the actual bricks though. I have been here with projects before!

I am going to do 3 sailor courses (like you did IIRC) and then the arch - so I will know pretty soon.

[GianniFocaccia]

Re: 39" Stargate Pompeii

Dennis,

Funny, the first time I ever considered angling my arch bricks was after viewing the transition you cited. It took me a good six months during the construction of my backyard patio, oven stand and design phase to get my arms wrapped around an approach that allowed for a more symmetrical arch.

Can't wait to see how yours turns out.

John

[deejayoh]

Re: 39" Stargate Pompeii

Wow Amac -
you are making really good progress on the oven. I think you started your stand about the same time as me. I just got my hearth poured last weekend and have yet to start on the dome, and you are working on your sixth course... I feel so slow

Oh well, not a race!

For the arch/dome transition - I am planning to take the approach shown in the 4th picture down on this site for the last row.

Might work for yours as well judging by the photos.

Nice work with the grinder!

Dennis

[Amac]

Re: 39" Stargate Pompeii

Thanks for the kind words John. I think it is a bit early to suggest it as a tutorial for anyone else - there are lots better out there. I am am quite happy with it so far. Knowing I have to post a few photos makes for taking a bit more care than I probably would have.

Rain stopped about 3 pm so I got a few bricks laid. Row 4 is finished and now begins the more difficult rows. According to my calculations it I should have no more than 9 rows before the plug to seal the dome maybe less if I lower the height. I'm having second thoughts on that.

In hindsight, each arch-touching horizontal brick face should have been tapered like a trapezoid, with the deeper end towards the arch

I'm having trouble visualizing what you mean here.

I have a vague idea that if I find I have to cut a very narrow strip - then I will turn the brick on end and make its end to the top of the next row above. When I was cutting the floor I found I had cut a few tiny slivers. It wasn't until afterwrds I realised that I could have turned lengthwise bricks at right angles and made more solid cuts.

light was fading for todays photo - all the best
Aidan

[GianniFocaccia]

Re: 39" Stargate Pompeii

Aidan,

You're doing just fine, exceptionally well, actually. I think your oven is the perfect tutorial to show prospective builders what can be done using a hand-grinder.

As you complete the courses approaching and exceeding the top of your inner arch you will see (and feel) first-hand why the droop occurs. There are many differing angles involved and I think it takes an experienced mason or a prior oven build to understand what's involved before you are able to adjust for it.

I should have given you a heads up on this since your arch (just beautiful, BTW) is very close to mine. My advice is to cheat the horizontal dome bricks upwards with an extra 1/16th-1/8th" of additional mortar. It may look funny at the time, but will overcome some of the droop. Look at pics of the front of my oven above the arch and you can see that I adjusted for this somewhat, but ultimately not enough.

Each of my dome bricks was tapered from front to back. In hindsight, each arch-touching horizontal brick face should have been tapered like a trapezoid, with the deeper end towards the arch. This extra brick mass would have taken up the space the extra mortar did and left nice, uniform joints throughout. Alas, next time!
John

[Amac]

Re: 39" Stargate Pompeii

Row 3 finished - and on the 4th - oh oh do I detect bit of tht dreaded arch droop.
I put my spirit level on this for the first time today and it looks like it is down slightly on one side - nothing major - I think my seams got gradually thicker on the inner horizontal edge as I circumnavigated the globe (ahoy there Cap'n cook! )
latest pics
I notice that the outside horizontal joint gets wider at each course - see the first pic. Anyone else notice this phenomenon. I think it must be something to do with the IT design. I was expecting them to be the same. I guess it will all work out in the end - but ...

The different IT designs are:
1. Hendos - it is more simple and takes a direct line from the dome centre to the top of the brick.
2. Jcg31s which takes a direct line from the centre of the dome to the centre of each brick.

It means that the bricks on each course lie at a slightly different angle depending on which design of IT you choose.

Maybe the jcg31 desgn also cause the widening of the joint? Maybe it my bad workmanship. I suspect the latter - must go back to the drawing board on that one

Later edit:
Well it works perfectly on paper - so must be something I am doing wrong
Aidan

[Amac]

Re: 39" Stargate Pompeii

Did you mean that you already have a few cracks or just that you already have a few vertical joints?

No not cracks - yet, but a few vertical joints. Sometimes, because of the particular slant the brick is cut at, the vertical joint appears on the inside but not on the outside or vice versa. They are hard to avoid

As to copying my build - since I am trying to copy others, especially Giannis - which is a work of art, very clean and beautifully cut, as well as the fact that they have completed and working ovens - I recommend you look to there first. Check out these builds compiled by Lburou
http://www.fornobravo.com/forum/f2/n...res-15133.html

I'm still feeling my way to a huge extent so as an ancient proverb says:

"Nor does the non-expert teach the non-expert -- any more than the blind can lead the blind."

What I found so far is that it is amazing what you can do with an angle grinder. In fact I would say with a slightly better eye and a good blade almost any cut is possible to do well, and what you don't do well is anyway never seen or disguised by mortar. The bricks don't need to be clamped down - I just have three pieces of wood screwed to an old pallet which the brick sits in snugly. I mark it all the way round, usually with a pre-cut jig, on both sides. I cut one side halfway through - and flip the brick over to cut the rest.
I think most people on here though use a reasonably priced, Chinese made brick saw from Harbor Freight which doesn't seem to be available this side of the pond, and does brilliant cuts - again with the right blade.

2.5 Horsepower 10" Industrial Tile/Brick Saw | eBay

Regarding cracks - I don't really expect to get any until I do some firing, and then it seems like even the best built suffer them in varying degrees, so I have resigned myself to expect them. Maybe then the vertical joint will act as a sort of "fuse" and break before the brick itself cracks which would not be so bad - it could be repaired with some fireclay or a sand fireclay mix.

Anyone know a build with no cracks. Gianni - I don't remember offhand if yours had any?
Aidan

[sharptailhunter]

Re: 39" Stargate Pompeii

Aidan, I think you're doing a fabulous job on yours. It looks very tidy and neat. I plan to follow your example throughout my build. I wonder why most of the cracks that do occur seem to come more easily to the vertical joints? Did you mean that you already have a few cracks or just that you already have a few vertical joints? Either way, keep up the good work, I'm excited to see how it turns out!

[Amac]

Re: 39" Stargate Pompeii

There may be more to it than appearance. Cracking appears to be more common in continuous vertical joints than joints that were carefully staggered.

Funny you should say that John - shortly after posting that I was just looking at pic that Aegis posted and it shows the inside of his oven with what looks like a crack on exactly such a joint. I better take a bit more care - I think I have a few of these already.
I agree that JR parks one is good - but still I prefer the look of yours - and that's what I'm aiming to get close to
Aidan

[GianniFocaccia]

Re: 39" Stargate Pompeii

I just think about that continuous plane (semicircle) as a variation of the continuous seam on all the horizontal (and at the top almost vertical and circular) rows, so in one sense it is almost impossible to eliminate continuous seams. Which is why I feel that aligning two bricks on different rows with the vertical seams continuous, is of little consequence other than appearance.

There may be more to it than appearance. Cracking appears to be more common in continuous vertical joints than joints that were carefully staggered.

Regarding someone integrating his inner arch into the dome, here is a pic of JR Parks' design, which is artfully done and looks really strong. Regarding gravity and strength, because of the 'hanging' nature of the V-cut brick and other designs, I vote for the tapered relief hands down.
John

[sharptailhunter]

Re: 39" Stargate Pompeii

Which is why I feel that aligning two bricks on different rows with the vertical seams continuous, is of little consequence other than appearance. I do try to avoid it but I won't go to a lot of trouble to do so.

I see it the same way you do. We've seen people on here all worried about having two vertical lines lining up but they forget that with each and every row, they are creating one really big horizontal mortar line. Like you said, appearance wise, it looks better to stagger the lines.

Believe me, I did put some thought into building the whole dome and then cutting out the entry arch. Then I realized how silly that idea was.

Yeah, Idaho winters can be long. It's killing me seeing other people progressing right along. Oh well, it gives me time to really study what good builders like yourself are doing so I can hopefully have the same success that you guys are enjoying.

But enough with the semantics, get back to work! I'm itching to see your final product, I'm sure it will be a beauty!

[Amac]

Re: 39" Stargate Pompeii

Hi sth

And I know I'll probably get flamed for this, but I disagree that your arch is truly integral with the dome. I say that because inevitably you will still have one continuous mortar plane along the inner side of your arch.

True I guess - but a real integration would be to build a complete hemispherical dome without an opening. and then use a plunge saw (or even that angle grinder that I use) to cut an arch - I would say it is possible and someone will surely try it Of course there would be a bit of brick wastage - then again attach some hinges to the cut out and you have a brick door as well.

I just think about that continous plane (semicircle) as a variation of the continuous seam on all the horizontal (and at the top almost vertical and circular) rows, so in one sense it is almost impossible to eliminate continuous seams. Which is why I feel that aligning two bricks on different rows with the vertical seams continuous, is of little consequence other than appearance. I do try to avoid it but I won't go to a lot of trouble to do so.
I do disagree about those V shaped cuts though
I am looking forward to seeing how you get on. I had a look at your thread and it seems the Idaho winters are not ideal for building, and you seem to have a fairly ambitious project. Good luck with it. I really appreciate any comments btw and thanks for taking the trouble
Aidan

[sharptailhunter]

Re: 39" Stargate Pompeii

I agree that the term "transition" could be used loosly in your situation. But then again, I consider any change in orientation of building units (bricks) to another orientation to be a transition. As such, I'm implying that those who use vertical soldier units then horizontal dome units are transitioning from one to another.

And I know I'll probably get flamed for this, but I disagree that your arch is truly integral with the dome. I say that because inevitably you will still have one continuous mortar plane along the inner side of your arch. In my opinion, for it to be integral with the dome, one would "integrate" the arch and dome pieces, i.e. overlap the bricks of each entity thus eliminating the continuous plane. I conceive that those who cut V shaped notches into each brick that connects with the arch are actually integrating the pieces more than those who expose a tapered relief on the arch, such as your design.

All that being said, I am planning to do exactly as you, and the others you mentioned, have done. To me, it's a cleaner way of doing it. It also appears that it may save some time in the long run. But with all the hours we put into our ovens, that small time savings essentially matters not.

[Amac]

Re: 39" Stargate Pompeii

It's looking great. You gotta be pleased with the way it's coming together?! I really like your dome to arch transition. Looks like you'll avoid the droop by the top of the arch as well. Good job!

Thanks sth - I hope so - the proof of any pudding is the eating so I'm keeping fingers crossed. I do believe this design of the arch has made some parts of the job easier.

I really like your dome to arch transition

I find this terminology in relation to the inner arch a bit misleading. To my mind the dome and arch are part of an integral unit. "transition" implies you are going from one thing to another separate entity. Hence questions like "where in the dome should I position the arch?" only make sense where you consider the dome and arch as distinct. Karangi Dude, Giannifocaccia, Sharkey, Aceves and others realised this. It was then a small step to understand the implcation that if you maintain the integrity of the semicircle/hemisphere that all the bricks in the arch could be cut from the same template.
Aidan

[sharptailhunter]

Re: 39" Stargate Pompeii

It's looking great. You gotta be pleased with the way it's coming together?! I really like your dome to arch transition. Looks like you'll avoid the droop by the top of the arch as well. Good job!