A couple pompei queries

[rwiggim]

Hello all,
I am ready to start building the dome today and have tried to self-research, with mixed results, on whether the soldier course needs to be mortared to the floor or not. In some photos it appears as if it has and others not. I seem to remember reading somehwere that they shouldn't be so they could move independent of each other. Then I saw a few pics where it looks like people come back and cover the whole dome in a layer of refrac mortar?

Also I plan on cutting bevels on the bricks so they fit more snuggly without such a mortar joint and was wondering for the second course on whether people were beveling both sides and top and bottom or just top or bottom? And is there a time period I should wait between course so I don't disturb the course before? Like if I did two courses today should I wait for a couple days for that mortar to really set up before I work on the next few? I guess I should say that I plan on making my own mortar with fireclay, lime, cement and sand. If I make the mortar correctly and soak the bricks for an hour prior do I need to wet the mortar anymore while it cures?

I am doing a 42" oven as a hybrid between low and high vaultm and I just guessed the oven height opening and opening height from the 36" high dome in the FB plans would be about what I needed.
Dome height 18"
Opening 19"
Opening height 12"
Any suggestions. I don't need a ton of room to get big roasts in and I like the idea of keeping heat.

Thanks again for the help, I plan on posting a thorough thread when I get near the end but with an 8 week old my work on the oven is sporadic at best.

darren

[nissanneill]

Hi Darren,
I have recently completed my Pompeii and have tried to explain it's construction and details with photos commencing at:

http://www.fornobravo.com/forum/f8/n...-1-a-2005.html (Neill's Pompeii #1)

then continued with the build where the oics were supposed to be at:

http://www.fornobravo.com/forum/f21/...-4-a-2045.html (Neill’s Pompeii #4)

and then again at:

http://www.fornobravo.com/forum/f21/...10-a-2119.html (Neill's Pompeii #10)

because one of my postings was moved.
I tapered and mortared my soldier course onto the vermiculite base and did 3 or 4 courses with the initial mix of mortar. I would do the same over again when I build my son in law's Pompeii later in the year so go for it!
Hope this helps. email me if you have any other specific queries.

Regards, happy building and good luck


Neill

[Hendo]

Originally Posted by rwiggim

... I plan on cutting bevels on the bricks so they fit more snuggly without such a mortar joint and was wondering for the second course on whether people were beveling both sides and top and bottom or just top or bottom?

Darren,

For my 43” Pompeii, I elected to get tapered bricks, as they were basically the same price as standard firebricks. I initially planned to just cut them in half and so end up with deep radial vees on the outside of the dome. But my brickie persuaded me to taper the sides of each brick to minimise these joints. The refractory mortar I’m using has a thickness limit of 2mm max, so it means good brick-to-brick joints are essential. I was a little concerned at how long this might take, even with a wet diamond saw, but I’ve managed to set up a rig on the saw table, which is better explained in the pics in my post at http://www.fornobravo.com/forum/28/t...html#post12106 (Tapered Cuts).

The first “floor ring” using 30 standard half bricks took around 60 minutes for the lot! However, subsequent rings can not be simply flipped upside down, as there is a top and bottom orientation as the bricks increase in angle. I’m still messing around with ways of lifting the bricks the required amount for the higher courses, but as far as cutting goes, it really doesn’t take long when all is set up accurately. I like a challenge!

See photo’s below for an idea of the results for the second and third rings. While I’m happy with the results so far, I’ll let you know how I fare on the upper courses. If all else fails, I’ve got a bag of alternative refractory mortar which is OK for greater thicknesses.

Originally Posted by rwiggim

And is there a time period I should wait between course so I don't disturb the course before? Like if I did two courses today should I wait for a couple days for that mortar to really set up before I work on the next few? I guess I should say that I plan on making my own mortar with fireclay, lime, cement and sand. If I make the mortar correctly and soak the bricks for an hour prior do I need to wet the mortar anymore while it cures?

While my mortar sets up really fast, NissanNeill would be better placed to comment on this, as I think he used a similar mortar to what you’re proposing. He also has some practical advice at http://www.fornobravo.com/forum/f2/m...html#post13233 (mortor thickness concern) regarding tapers.

Originally Posted by rwiggim

I am doing a 42" oven as a hybrid between low and high vaultm and I just guessed the oven height opening and opening height from the 36" high dome in the FB plans would be about what I needed.
Dome height 18"
Opening 19"
Opening height 12"
Any suggestions. I don't need a ton of room to get big roasts in and I like the idea of keeping heat.

Your opening has similar dimensions to mine, which will be a high vault (21½ ”). My only concern now is that a slightly wider opening (mine is only 18”) would have made manipulating things around in the oven easier, especially as my vent will be the same width and protrude about 12”. But like you, I like the idea of keeping the heat in.

Hope this helps,
Paul.

[rwiggim]

Thanks for the input.
darren