Is Mortarless Realistic?

[GianniFocaccia]

In reference to the recent thread 'To taper or not to taper' located here:

http://www.fornobravo.com/forum/f8/t...per-16164.html (To taper or not to taper?)

cholme illustrates profiles of three kinds of dome construction styles: mortarless, tapered with mortar, and untapered with mortar.

Because I have yet to see a true mortarless oven on the FB site (precast ovens don't count) I am wondering if this is an ideal or truly possible (transition construction and stability nothwithstanding).

Further, since mortar seems to play an important flexural role in the dynamics of an expanding/contracting dome (in addition to it's static stability), is it possible to go 'semi-mortarless? This would be where the inside/outside joints reveal no mortar, yet there is a small cavity between bricks that contains 1/8" or so of mortar to keep the bricks stable when going vertical during construction.

If someone has built a truly mortarless oven I would love to see pics of it.

John

[SCChris]

John,

My answer is "No" it's not realistic, but it can be done..

As you know I tapered and used mortar. My reasoning has always been that the dome is just a pile of bricks that are self supporting and mortar fills the gaps. I feel that if every brick is tapered and is always being pulled inward because of the taper shape and gravity, then even if cracks are present and mortar isn’t, the structure is sound. Now this said, I’d hate to try to keep a mortar-less dome oven, built with straight cuts, hot. I haven’t seen an oven in FB that didn’t need some mortar. I can imagine 2 ways to build a mortar-less oven.

1: Cast different bricks for each course this would allow the bricks to match the surrounding tightly on the four contacting faces.

2: Use a wire saw to cut each brick. The wire saw can cut the cone of each course and the sides of the bricks without gaps. Of course, gaps would occur anyway due to the differing particle size and density of the bricks and each brick, but I think a free standing dome could be built with a wire saw in a timely manner. I’d still insulate the H E double toothpicks out of it.

It’s fun to think of the alternatives, but without the resources and time.. Sigh..

I'd love to have an endless R&D budget. Come to think of it, I'd just be happy to have a budget..



Chris

[cholme]

Just to clarify, the drawing I posted with no mortar was not to propose a "mortarless" dome, just to illustrate that if you did taper each brick to fit the arch, you would possibly have more of a mortar joint inside the oven than with square bricks.

I would concur that a mortarless oven would be a bad idea.

[Les]

The dome could be mortarless but I think you would need some to tie in the arch. Even this area would be possible but it would require a fair amount of engineering time (not to mention the crazy cuts I envision).

[gt40]

This is the closest to mortarless I have seen:

STOVEMASTER - News

[ggoose]

Impressive build gt40...

[Ken524]

Originally Posted by GianniFocaccia

is it possible to go 'semi-mortarless?

John, check out Les' semi-mortarless oven.
Amazing work.

http://www.fornobravo.com/forum/f8/les-build-4207.html (Les' Build)

[GianniFocaccia]

Right on, Ken. I had replied earlier to gt40's Stovemaster link but for whatever reason it didn't go. It went something like this:

gt40 - that's the prettiest oven I've ever seen except, uh, Les' build...

[dmun]

Best transition I ever saw:

[Tscarborough]

That is a thing of beauty, it is called a jack arch.