North Wiltshire build

[mutteringfool]

Just kicked off my build so thought I'd start a thread here, although I will say from the start it isn't going to be a smart and neat oven with lots of nicely cut fire bricks 
I'm going for the simple, rustic approach and have a guide a friend wrote that I'm following in general with a few tweaks.

The base is going to be made from sleepers stacked up and then a few more sleepers horizontal to give the platform to build on.
Then (based on tips on here) plan to use thermalite bricks for the hearth insulation with either paver's or fire bricks for the hearth. Then the dome will be made from red house bricks which I have a nice pile of for free from my garden and also the neighbours garage that they recently knocked down. 



This is the site which I thought was perfect as it's paved and flat already. But first question for you guys if you don't mind, the slabs are laid on concrete but only a relatively thin layer.
Is this really going to be a major problem and so I should take some up and put a proper concrete base down? Or can I risk it?

Second question I'd intended on using paving blocks (meant for driveways) for the hearth. They're 50mm thick so in theory thick enough but will they do the job ok? 

[mutteringfool]

Lots of deliveries this week including a nice order from Vitcas
Managed to get some work done today with my brother; built up the top of the plinth with the sleepers and got them all screwed down.
Then we covered the base with aerolite blocks for insulation, considered cal sil board but having read about the blocks on here decided to go with them and a whole lot cheaper. Although did mean a re-jig of the base with some bricks under the blocks to get the height right as I'd worked out the dimensions for the board.
Finally we got most of the hearth stones laid, went with fire bricks in the end as was about £40 more than pavers and I thought that was a good investment. Took a bit of head scratching to get the brick pattern set up in a way we were happy with. Have tried cutting some of the corner bricks but not great success with a bolster. 
Reading on here an angle grinder sounds the best option? Any other suggestions? 

Now have all the materials I need so hopefully may get the first layer of bricks done in the next couple of days.

[rokdok]

Hi MF, I used an evolution mitre saw - 255mm. As Bookendanno has said it'll cut through bricks like butter. Soak them first though. You'll need a diamond blade- make sure you get the right bore. Evolution do recon B/C stock. I used a 255mm for my build - you could go small (or bigger) Heres the link to their ebay shop www.ebay.co.uk/sch/evooutlet/m.html?_nkw=&_armrs=1&_ipg=&_from= Cheers RokDok

[tonyb]

Hi,I used a cheap 115mm angle grinder and diamond discs from Screwfix I think. I cut a line across about an inch deep the used a bolster to separate the 2 halves, only messed one brick out of 200, and the rough cut side is covered with the insulation so not seen. The larger 225mm grinders can cut fully through the bricks but are more expensive and quite a bit more dangerous to use because of size and weight. Soak the bricks first as suggested by Rokdok, it makes the cutting easier and less dusty, don't forget to wear a dust mask.

[kstronach]

hi

congratulations on starting your build! good choice to avoid the concrete block pavers for the hearth they would have been no good at all! also i think you'll be fine building off those flags, i built mine off an existing patio that is just laid on whacked hardcore it hasn't settled at all.

keith

[mutteringfool]

No update for a while the distraction of a holiday and running a marathon have meant zero progress. But I'm back on it now with the motivation to be done for a big family BBQ on 20th July
Cutting fire bricks has been interesting, have had better results with a hammer and bolster than angle grinder though. Not perfect but it won't change the taste of the pizza will it?!
Hearth is basically done now and I've cut into the sleeper for the front bricks to sit on. Have also made a template for the oven size to act as a guide, really helped me seeing it visually like that.

Hopefully going to get the first few layers done this week. Before that a couple of questions; plan is to have a 32" internal diameter oven with a 17" opening and a 20" arch height. Does that sound about right?

Second question, I don't have room for a long entrance (which I knew from the start) so what's the best way to build the chimney hole in? Do I just do a couple of half bricks at the top of the arch to leave a gap behind? Or do full bricks and fit chimney into the front of the oven itself?

Final question; what are my chimney options? I quite like the idea of a terracotta one but is that just impractical? If mental any recommendations on cheap sources?

[mutteringfool]

I have some bricks up! Actually quite pleasing to be building the oven itself, although allow me this moment of glory before you take a hard look at my poor brick working skills
For an office worker who's never laid a brick before though I think I'm doing ok. Also having a log burner installed at home in a few weeks and the guy doing it is going to get me a spare piece of flue for my chimney.

Built the form for the entrance arch tonight so hopefully get that up tomorrow night and then crack on with the bricks.

A question on the pointing, what's the best way to clean up the bits on the brick and do I need to bother?

[cobblerdave]

Jun 24, 2014 20:46:37 GMT mutteringfool said:

No update for a while the distraction of a holiday and running a marathon have meant zero progress. But I'm back on it now with the motivation to be done for a big family BBQ on 20th July
Cutting fire bricks has been interesting, have had better results with a hammer and bolster than angle grinder though. Not perfect but it won't change the taste of the pizza will it?!
Hearth is basically done now and I've cut into the sleeper for the front bricks to sit on. Have also made a template for the oven size to act as a guide, really helped me seeing it visually like that.

Hopefully going to get the first few layers done this week. Before that a couple of questions; plan is to have a 32" internal diameter oven with a 17" opening and a 20" arch height. Does that sound about right?

Second question, I don't have room for a long entrance (which I knew from the start) so what's the best way to build the chimney hole in? Do I just do a couple of half bricks at the top of the arch to leave a gap behind? Or do full bricks and fit chimney into the front of the oven itself?

Final question; what are my chimney options? I quite like the idea of a terracotta one but is that just impractical? If mental any recommendations on cheap sources?

G'day
That dome and door hieght is a bit high for a 36 in oven. Your building an oven that works on heat radiating from the brickwork and that dome will be to high off the food.
A 36 in oven should have a internal dome hieght of 16 ins or lower. A dome height of 16 ins needs a door height of 11 ins and door width of of under half the width of the oven so 16 in or smaller to work well.
My view of the entrance way if you are making it deep make it wide as well . This way it will make it easier to work and see into your oven.
With the chimney you going to need 15 per cent of the area of you door to draw well so a 7 to 8 in steel pipe or pot will be needed to draw well. I don't know much about chimney pots to offer much advice , but I think they look great.
One thing I would recommend is to build in a smoke chamber above the oven door. As wide as the entrance so you have a space for the smoke to collect and be funneled into the chimney proper. Stick a 8 in pipe above a 16 in wide door and most of the smoke will bypass that pipe, arch or no arch.
Hope something in here helps
Regards dave

[dirtlover2005]

I've been looking at chimney options and it seems they fetch quite a few £ on the bay and any cheap ones are always miles away.

I've been offered varying sizes of single skin flue pipe that I may end up going for. I had thoight about 6 inch clay drain pipe and cutting it to size.

[mutteringfool]

Cheers Cobblerdave, I realised the error on the arch size when I started making the form! I'd done 65% of the total oven width rather than just half of it.

Tried building the arch tonight and I have to say it was infuriating. I rebuilt a few times as if I moved the bricks too much they'd come loose from the mortar. Any top tips here? I got all done apart from the final couple of bricks, but I've a feeling it's going to need a rebuild.

[dave]

G'day
I think your trying to do 2 much at the one time. Time to slow down and solve each problem as a separate piece.
First build the dome with its arched oven mouth, don't worry about building the entrance/chimney that can wait. I find this works for me get a ruddy big hunk of cardboard and draw out a top view of your dome. Then a section side view through the middle of the dome (don't forget the brick thickness)you'll then find out how you dome and arch intersect.
After that its time to build your entrance with its smoke chamber over the door funnelling smoke up to the chimney.

ukwoodfiredovenforum.proboards.com/thread/1459/another-glasgow-pompeii?page=1

the links to JMS's oven a really good looking oven and shows the entrance way pretty well notice the brick around the oven mouth allows for a door to fit up the mouth

Arch building, after getting yourself an idea of the arch's placement its building the arch support so it can be removed without destroying you brick work. My first arch did!
Cut yourself a profile of the arch shape from Ply Chipboard whatever. Screw Two battens on the first profile vertically. Then screw the second profile to those battens. Set an electric saw to cut through the material width of the profiles without cutting the battens and cut through both Horizontally. The resulting arch profile can then be unscrewed into bits and removed easily ( screw it back together and keep it as a pattern for a future door)

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Hope something in here helps

Regards Dave

Regards Dave

[mutteringfool]

Thanks Dave - I'm doing a slightly different design to most so no separate internal arch, but I did the arch over a few days instead and worked perfectly.





Progress has been going ok but only have time to do a layer a night at most. Also ran out of bricks at one point from my original stash but fortunately discovered my neighbour had a load I could steal from. He also has these bricks in amongst the normal ones, anyone know if they're ok to use? Seem solid enough and when chopped in half the make up looks fine.

[mutteringfool]

Pushed on over the weekend and managed to get the dome finished late last night. Ended up doing the last row in the dark at 10pm but worth the effort to have finished I think. Getting the bricks past the entrance arch took a bit of working out, not perfect but I think solid which I guess is the important thing.

Used some sand on top of plastic and then bricks to do the last couple of layers, took them down tonight and it looks ok. Needs a bit of work on pointing but otherwise I'm happy. Using red bricks is cheaper but doesn't make quite as tidy a build as fire bricks I don't think. Plus I used a hammer and bolster for the vast majority of cutting just for simplicity rather than spending the time with a saw. 

Taking a break tonight to enjoy finishing this stage of the build and will get the insulation on later in the week.

[mutteringfool]

Evening. I managed to get the vermicrete on towards the end of last week. Thought that was going to be the easy bit of the build but turned out quite fiddly. Not sure if I didn't have quite the right consistency but there were a few collapses and rebuilds. Also any spot where the chicken wire moved was prone to knocking off whatever I put on. But it's done and weather has been great, couple of heavy showers on Saturday but otherwise it's been drying out nicely.

So I lit the first small fire tonight, in a strange kind of way I'm going to miss having it to build! That might change when I taste the first pizza of course
Also very pleasing that even with no chimney fitted at least 90% of the smoke went up through the smoke box rather than out the front of the arch, I guess it'll be even better once there is a chimney on top to help with the draw.

I'm going to render it at some point, question is can I smooth out some of the lumps and bumps of the vermicrete with the render? Or should I try and get another thing layer of vermicrete on to do that?

[rokdok]

Congratulations, I know what you mean - there is a tinge of sadness when you come to the end of the build. You can't have too much insulation and if you've got room I would put more vermiculite on. RD