Tanzania/Canada

[cobblerdave]

Re: Tanzania/Canada

SteveS
Pics are good so don't worry. Your works looking very neat especially considering you doing the brick cuts with an angle grinder!!! I recon it will be a little harder now you'll have cut the brick size down as the curve at the top gets "tighter"
Any thoughts on the insulation layer over the dome your using a local plumice mix arn't you?
Thanks for the info on the "Tanzania Home brew mortar". Thought it would give a good mix because after the termites digest the stuff the only thing left is clay and sand any thing of an organic nature is long gone. Nothing will grow in it... thats why it used to make tennis courts in the bush I recon.
The drips of home brew mortar that I found after I had burnt out the ply brace that supported my oven construction were still hard but a bit lighter than just the normally dried mortar lumps. Recon the heat broke down the cement leaving the clay lime and sand. You samples turn out the same way?

Regards Dave

[SteveS]

Re: Tanzania/Canada

Thanks Dave,

Thanks for the continued encouragement.

The formula that I am using is a slightly modified fireclay mix which is in the plans (1-portland cement, 1-lime, 1-fireclay, 3-sand). In my testing I tried to use ground down soft clay bricks that are made here for the fire clay and didn't feel comfortable with the results. I thought the use of termite mud gave me better results.

Mind you, the testing proceedure was pretty rudimentary!...making pucks out of different mixtures and roasting them on a grate over a wood fire. Not exactly a proper cure of the mortar before the high heat! I can only hope that I made the right choice. Time will tell!

In any event the termite mud that I get from the brick man is already processed by being sieved, premixed 4 parts termite and one part sand and let to stand for quite some time. By the time I get it the mix is moist and I think it has been passed through the brick making machine(large meet grinder) once and let to stand again under cover for a time. When he makes his final bricks he uses this material. The bricks are fired at about 900 degrees for about a month using smoldering rice husks. They come out amazingly hard.

I have a bucket of this mud which is moist and about as sticky as you can imagine. So what I do is take 5 cups of mud (premixed at 4-mud and 1-sand),
11 cups sieved sand, 4 cups lime, and 3.5 cups cement. That gives me the 3-1-1-1 mix being a touch light on the cement.

I will let you know how things go with the curing.

Sorry about the pictures in these posts. I have registered this site with imageshack and for a while the images were ok and now were back to the frog in the icecube and you have to click on that....at least that is what I'm seeing.

Cheers SteveS.

[cobblerdave]

Re: Tanzania/Canada

SteveS
Looking good ....Damn good.
An old brickies saying is"fingers are for picking noses not for playing with da mortar" Never could listern that well .... play with the mortar I did ...many times... you can't help it can you....
Best tip I found on the forum wash you hands with vinegar yep just ordinary vinegar takes the sting away you will be suprised ....it works so well.
Well you are certainly well on the way if I could ask what sort of mix did you use in the mortar I could certainly use the input a mate from the west is to build an oven I'm to give him a hand. It will be a build from local materials and ther'es plenty of ant hill ( termite mound) to be found so the feed back on your build would be of great value. He has gone from Cob contruction to wanting some thing a little more long lasting

Thanks Dave

[SteveS]

Re: Tanzania/Canada

Hello All,

Well, I think that I can finally see the finish line....Whew!

Hope my fingertips don't fall off from the lime before I get done. Thought that I would pass on a few pictures of my progress...actually have one more chain done than the pictures show.

Tomorrow I hope to finish the dome and pipe mortar into the interior joint spaces.

Cheers, SteveS.

[SteveS]

Re: Tanzania/Canada

Thanks Dave,

By the way, I just cut the forms for the arch! Thanks for the inspiration!

[cobblerdave]

Re: Tanzania/Canada

Steve S
Sorry forgot.... simple just don't make the chimney to high....the oven doesnt smoke much except when first started



Dave

[cobblerdave]

Re: Tanzania/Canada

dear SteveS
Read your plans the important thing is, to use an Aussie term "Have a go" If you read the plans it calls up 38 per cent cilica fire brick mine are 29 per cent
Lite duty ... the plans say use them if thats whats there. As for Brick the danger is they will break down and "spald" but as qouted in the plans
"If your choice is to build you oven with clay bricks or not at all, we would strongly recommend building your oven with clay bricks"
Your bricks are not commons IE they have holes in them... but not large holes... they are not like normal house bricks where 1/2 the brick is empty space. you have filled the small spaces you have I recon you have bloody good chance to make it work.
My mate made an oven over 30 years ago in his back yard from clay from the next door buiding site with a old fuel stove door and insulated with soil and hay......worked well cooked a bloody good roast for 2 years at least.
Well that steel bar youhave seen is lintel bar used over doors and windows on brick clad houses by the way.
I have used angle iron with my sqaure entrance the danger I have always known would be rust.....apart from the normal rust expectd from the heat I live less than a mile ( yes a non metric term ) from the ocean.
I expect to relace the bar a some time I'll hold the brick work up and knock the old out and a new in ( yes I've made sure it's clear of incasing mortar and brick)... for the now I clean the oven of ash and rub with plain cooking oil on the steel.
Go Well and God Bless
Cobbler Dave
PS Please tell me the mix your using for the mortar a mates going to go a little low tec and I would like to know your results

[SteveS]

Re: Tanzania/Canada

Say it's not so Brickie! Sure will be disappointing it happens, especially since there's no plan B or alternative fire bricks. The brickman feels they will hold up. Hope he's right! Then again he's never fired a wood oven.

Another quick question. Since my vent is not angled out, if I choose to attempt an arched vent should I consider extra support or buttressing outside the vent walls?

[brickie in oz]

Re: Tanzania/Canada

It will be interesting to see how the hollow bricks hold up with the heat of a wood fired oven, popular consensus says that they will fail, and badly so.

[SteveS]

Re: Tanzania/Canada

Thanks for the encouragement and compliments, Dave...although I did not realize how long it would take to build an oven! I'm really enjoying the build but I have to pick up the pace as I'm not here much longer.

The thickness of the angle iron is 1/8 inch which is a bit lighter than 3/16. I notice on a photo on Forno Bravo that it appears that there is a piece of flat bar used as well. Am I seeing that right?

Cheers, SteveS.

[cobblerdave]

Re: Tanzania/Canada

Dear SteveS
Wow great progress!... impressed yourself...should be.
Thats a very neat job... went the upright course to start but at 1/2 height I noticed. filled the hollows in the bricks as well. Ha... how did you go with the "tanzania home brew mortar" which recipe made it through your fire experiments, I'd love to know.
Myself I would use the angle iron you have got it may not be as wide but 1/4 isn't it thicker than 3/16 th. Sorry a bit rusty on the inchs and feet these days.
Really though the brickwork impressive... I mean this, it's really neat why dont you consider an arch? I know your only working with an angle grinder but I recon you could pull of a great arch!
Don't worry about the angles were the oven meets the entrance because I recon they would just as mind blowing weather the entrance is round or square. (remembering I went the square path)
Will be watching your posts with interest
Regards
Cobbler Dave

[SteveS]

Hello Fellow Oven Builders,

I had hoped to move my entire thread that I had started Jan 21st over from Regional Forums but I really don't know how or even if it permitted. I probably should have started here in the first place in an effort to recieve more ideas or thoughts. I have copied my first post and left the 6 pages of questions, comments and replies there for those who arte interested in catching up.

Hello to all Pizza Oven Builders and Users!
My wife and I live in Simcoe, Ontario, Canada. 18 months ago we started an Orphanage in Usa River, Tanzania. It is a small village located between Arusha and the Kilimanjaro airport. For any of you interested our site is tuchifo.com helping children in East Africa.
We are here now and my wife is experiencing great success in teaching staff to prepare more healthy and nutritious meals for the children. We struggle however with the inefficiency of the cooking methods traditionally used here.
I am here until early March and am committed to make a wood-fired oven.
As you can well imagine obtaining materials for propper construction is always a challange in Africa. I am a farmer by trade and can pretty much make or fix anything with almost nothing.
Before I start searching for materials I thought I would post this thread to see if anyone has had experience in the Arusha area with aquiring fire brick or if indeed anyone has actually built an oven in this area.
Thanks for any help anyone can provide!

For now I would like to continue here with some updated photos of my progress and ask another question.

With regard to the angle iron for the vent, I know the recommended thickness is 3/16". I happen to have some 2"x2"x1/8" available. Has anyone used that thickness? Is that thick enough or will the heat make it warp?

Cheers, SteveS.