Spur of the moment build - bit of info needed

[garyou]

Hi all

Haven't used a forum since my OU days, hope this post comes out OK.

One favourite memory from my Navy days was eating fresh pizza in Palermo, Sicily cooked in a street side cafe with a huge WFO back in the very early 90's. For the past few years there has been a lot of talk but no action re a pizza oven.

Not anymore seven pints of carling late Saturday afternoon followed by a quick home delivery of special fried rice was all that it took to turn talk into action. Woke up Sunday with the footings dug. 23 bags of wickes ballast later and the foundation was complete.

Problem was I had no idea what to do next and thats where this great forum has helped, I found this thread Topic: Mark's Compact Barrel Vault Oven, both informative and very well written and decided to base my project on the same lines.

Now can anyone advise if the wood store cover is strong enough to take the actual oven? It is made from 35mm pavers sitting on both block work and concrete lintels. I don't know whether to add a second layer of pavers on motar over the first using staggard joints to give an 80mm lid. If you have any thought please pass then on, good or bad.

Friday 18th


Today Sun 20th






The wood storage opening is higher than I would have wished but just in case this projects a failure Mrs D might make me live in there for a while.

TIA

[rivergirl]

Hi and welcome, sorry I can be of no help but one of our bob the builders will def be ab
E to sort that one out.

[turkey]

HI Gary,

the base looks good to me, and impressive work for such a short time, are you in the trade as that brick front looks pretty darn square

Do you have a plan for materials to use for the oven itself, the heavier the load the more you might want to consider upping the hearth support. Firebricks are more dense and thus weigh more than standard bricks, so if using them its surprising how much weight will actually be sitting on the store.

Mark has more vertical lines of support under his oven, his will be pretty much under the side walls, where on this build I think they will be in the middle of the slabs over the void, so perhaps doubling up would be wise.

I would not stagger the joints too much as you want them to rest on all four sides on the supporting structure beneath. Your front slabs overhang the lintel so that void has a weak edge through the middle of it horizontally. I would do the second layer and cut them to end at each lintel.

Terry might have more of an idea as to the structural strength of these slabs,

[cannyfradock]

Hello Gary......welcome aboard

Although the slabs have not that much strength within themselves, the support base ....in my opinion is OK for laying a single slab on. Most of the weight/stress will be on the outer wall, and only insulation or render will be on the cantilever of the slab.

Don't forget insulation under and above the dome.

As you base is only 5 bricks wide, calculate before hand the insulation needed on the dome, before setting your dome out.

All the best with your build....and if in doubt....shout out.

Terry

[garyou]

Thanks for the feedback and kind comments, I'll sleep on the double lid til tomorrow.

I need to order items for the upper oven part, I'll try to explain this idea I have for the oven.

A base area of 1.15m x 0.8m, 1st layer 38mm vermiculite concrete, 2nd layer Cal Sil 25mm, dusting of fire clay and finished with 35 fire bricks 7 short side wide by 5 long side deep.

If the base is OK and good enough to build directly on, then starting from the rear of the pad build the main fire chamber just under 600 wide as the walls would sit on the outer fire bricks, the chamber would be 3.5 bricks deep as the last half brick would do a 90 deg turn to form the base of the back wall. The chamber has a planned height of 450mm ish with a 300mm ish entry port.

This would then leave me around 350mm depth for the front entrance for hopefully a brick built chimney depending on how it goes.

Now the contentious part, for the internal walls and arches how about solid red engineering bricks and home brew motar? Purely on a cost and ease of build point?

Finally smooth everything off, wrap in fibre blanket, foil and chicken wire before rendering with vermiculite comcrete 50mm and then re-rendering with smooth render allong with the blocks used in the base and then paint with masonry paint to match the garage which has the same brick front, block sides design.

Many questions I know, but if you are able to offer guidance please do cos my neck is on the block if it fails.....

Thanks again

[garyou]

Progress update

Gone for the single paver lid, I've been standing on it etc with the bricks with no issues. Main construction will be class b solid red with home brew mortar. 2" of blanket plus 2" of vermicrete plus render.

I'm looking for a compact easy to use oven the heats quickly, cooks well and looks well built. I was also looking at a tandoor but hopefully the temps in this oven will mean we don't need one.

Got in out of the garden tonight at 10:15pm after removing the former for the first arch.

Some pis of where we are up to:






The cooking area is around 700 x 570, with a height of 375, hopefully this will be OK


I bought the Cal Sil off cut value pack from KilnLinings and it appears to have worked fine, all the edges were true and butted together fine.

[turkey]

Looking very good there, and coming along at a good pace. Those slanted bricks seem a very good idea to form the arch against, I manually cut mine and are wonky and dam hard to mortar against.

The great thing about these barrel vault ovens is you get to practice with many rings of vault before you need to do the oven entry evey one will see, although you seem to have cracked it with the first set. I would scrape mortar overspill off the brick face on the arch so you have a nice flat face to key up agaist, its amazing how little things like some old dry mortar can hinder the next arch. For the final one / enterance I would get a bucket of water and sponge so you can clean as you go, I did not do this and will mean more of a clean up layer.

[garyou]

Update 27/05/12

my neck and arms are a tad pink and tender, this afternoon at 1.30 I have to give up bricking and go to wickes for more supplies cos it was just too hot, even submersing the bricks in a bucket of water before laying wasn't enough.

here is where we are up to:








hopefully the chimney stack will be finished tomorrow, then it's insulating the barrel, no too far to go now. I know Mrs D is quite impressed and now taking much interest - may be too much, I may have to put a line in the sand as I'm the outdoor chef..........

[garyou]

thanks for the advice Turkey, one more piece needed, how do you keep the oven floor clean when in use? I think I should have tiled it but its too late now. The pizzas will be fine but lamb and belly pork will make a mess, they will have to go in shallow roasting tins like in the oven.

[turkey]

most folk do use roasting tins purely as it catches juice and such with other veg in there also. I believe the oven fires that hot that fat and other material will be incinerated very similar to the self clean cycles crazily expensive kitchen ovens do so you could stick meat directly in. The pans also make it a lot easier yo get into the oven and more importantly from oven to plate for eating.

if you want rustic meat check out dirty steaks which you "grill" directly on the burning embers. They seem mighty popular ;-)

otherwise people have a copper wire brush on a pole to sweep the ash and give it a quick scrub, then use a bit wet cloth and wipe the floor, it will be sterile and dust free and the added moisture in the air helps with break.

[cannyfradock]

Gary

....Great progress. Turkey's comment is spot on....the only addition I have is a piece of copper pipe with one end flattened, to gently blow any ash to the rear of the oven before (and sometimes) during cooking batches of pizza's.

Terry

[garyou]

update 28/5

Hopefully all the bricking is done except the side shelves, lit a small fire to check the chimney design gathered all the smoke.

Now for insulating - I have the fibre blanket 1 inch thick and probably enough to do twice but does it need doing twice??

Also vermicrete, is this the easiest method over the blanket?

Thanks again

[turkey]

you do want as much insulation as possible so double it up if you have it :-)

re vermicrete, I have not used it but it is ment to be a little frustrating. Folks wrap the blanket in chicken wire first to give it something to grab.

[samuraidave]

That really is very impressive well done that man. I just have loose vermiculite over my barel and i find it does an amazing job. If you are putting a roof on then you can just loose fill. I am sure it is only minimal but vermicrete must increase the thermal mass of the oven? I may be wrong, it is not unheard of. Lol well done and keep us updated.
Dave.

[pete123]

I like your chimney. I've saved the links to my favourites so I can take inspiration from it.

Pete.