Fire in the Fens - My Vault WFO near Cambridge
May 27, 2016 11:16:01 GMT
awalker, oblertone, and 1 more like this
Post by barney on May 27, 2016 11:16:01 GMT
It's been a while since I've been on here, having completed my own build I naughtily haven't helped out many others... but hopefully just having this build diary up there has been of some use to those following behind me.
Well, time for an update.
For reasons of poor design, I've never been entirely happy with the functioning of my oven. The vault seemed too high and it was difficult to get an even cook on the pizzas, I always ended up doing a big turn on the peel against the roof of the oven. I had built a barrel vault on the same basic principle as the pompei, working with a semi-circular arch on a couple of level courses of brick. I changed my brick size in an attempt to save cash and went for thicker bricks, however I didn't consider the impact this would have on the bottom courses, raising the arch too far from the cooking floor.
The way I saw it I had two options: either lift the arch and remove the bottom courses; or remove the arch and change it for a flatter profile. I preferred option 2, but the thought of taking my oven apart on a whim was troubling, so it took me quite a while to start. I finally bit the bullet and got on with it, the transformation over the last few weeks is as follows:
First thing was to dismantle the main body of the oven and clean all the bricks in the hope of reusing them to rebuild it. This was the most difficult bit, the homebrew I had made was worryingly crumbly and came off relatively easily, but the fire cement had set like rock and was well stuck to the bricks. Cue lots of chipping, chiselling, thumb hitting and cursing...
Then it was back to basics for some complicated arch calculations using the handy online calculator and the creation of some new forms. From there it was just a case of using all those leftover bits which have been sitting in my garage for a few years (and thankfully didn’t get any takers in the classifieds section!) to stick the bricks with fire cement and then mix up some gap-filling homebrew to slather over the top.
Much the same for the smaller front arches with a carefully (and yet still inexpertly) cut bridging section for the flue to sit onto. Final front arch was thankfully the best of them all, as this is the only one which will be visible at the end!
After letting it all set for a suitable period of time (longer then the first arch which collapsed due to my impatience!), the re-work is complete and looking pretty good, at least from the front.
Inside it’s a little rougher, but at least I have achieved exactly what I set out to do and have lowered the interior ceiling by a significant amount.
After casting, installing and painting a new front for the reduced arch, it could be backfilled with vermiculite and then a new roof constructed over the top.
The finished article is not at all shabby in my opinion, and when fired up (after a couple of small drying fires) it gave a much more even bake to the few experimental pizzas we chucked in on a Saturday night.
So would I recommend it? Really not sure. It was a lot of effort getting the thing down and cleaning up the bricks, plus you are then back at almost square one, albeit with a better idea of how to move forward.
Obviously one of the main reasons I am sharing this is to encourage people to get it right first time; measure twice, build once is the motto here!
If I had thought about it properly to start with the base would be higher so you don’t have to bend down so far to see inside, compounded now by the reduced viewing angle and the deck I added underneath. Although I think I could probably do all the baking from a bar stool…
The main thing is about the cost:benefit ratio, and having not had much of a chance to use it I’ve yet to calculate that completely, however as the cost was so low (reused materials and leftovers), I think it will come out as a worthwhile endeavour.
Well, time for an update.
For reasons of poor design, I've never been entirely happy with the functioning of my oven. The vault seemed too high and it was difficult to get an even cook on the pizzas, I always ended up doing a big turn on the peel against the roof of the oven. I had built a barrel vault on the same basic principle as the pompei, working with a semi-circular arch on a couple of level courses of brick. I changed my brick size in an attempt to save cash and went for thicker bricks, however I didn't consider the impact this would have on the bottom courses, raising the arch too far from the cooking floor.
The way I saw it I had two options: either lift the arch and remove the bottom courses; or remove the arch and change it for a flatter profile. I preferred option 2, but the thought of taking my oven apart on a whim was troubling, so it took me quite a while to start. I finally bit the bullet and got on with it, the transformation over the last few weeks is as follows:
First thing was to dismantle the main body of the oven and clean all the bricks in the hope of reusing them to rebuild it. This was the most difficult bit, the homebrew I had made was worryingly crumbly and came off relatively easily, but the fire cement had set like rock and was well stuck to the bricks. Cue lots of chipping, chiselling, thumb hitting and cursing...
Then it was back to basics for some complicated arch calculations using the handy online calculator and the creation of some new forms. From there it was just a case of using all those leftover bits which have been sitting in my garage for a few years (and thankfully didn’t get any takers in the classifieds section!) to stick the bricks with fire cement and then mix up some gap-filling homebrew to slather over the top.
Much the same for the smaller front arches with a carefully (and yet still inexpertly) cut bridging section for the flue to sit onto. Final front arch was thankfully the best of them all, as this is the only one which will be visible at the end!
After letting it all set for a suitable period of time (longer then the first arch which collapsed due to my impatience!), the re-work is complete and looking pretty good, at least from the front.
Inside it’s a little rougher, but at least I have achieved exactly what I set out to do and have lowered the interior ceiling by a significant amount.
After casting, installing and painting a new front for the reduced arch, it could be backfilled with vermiculite and then a new roof constructed over the top.
The finished article is not at all shabby in my opinion, and when fired up (after a couple of small drying fires) it gave a much more even bake to the few experimental pizzas we chucked in on a Saturday night.
So would I recommend it? Really not sure. It was a lot of effort getting the thing down and cleaning up the bricks, plus you are then back at almost square one, albeit with a better idea of how to move forward.
Obviously one of the main reasons I am sharing this is to encourage people to get it right first time; measure twice, build once is the motto here!
If I had thought about it properly to start with the base would be higher so you don’t have to bend down so far to see inside, compounded now by the reduced viewing angle and the deck I added underneath. Although I think I could probably do all the baking from a bar stool…
The main thing is about the cost:benefit ratio, and having not had much of a chance to use it I’ve yet to calculate that completely, however as the cost was so low (reused materials and leftovers), I think it will come out as a worthwhile endeavour.