First off I'm basing my Pizza Oven on Minesamojito's oven. All credit to him!!!
Found his website and loved the idea of re-using and recycling materials to make the oven and hopefully keep the price down.
Fire bricks and refectory cement is very expensive here in New Zealand.
My plan is to build a heavy timber frame base and line the sides with 50mm precast concrete panels. 100mm concrete slab, 75-100mm vermiculite slab, 2 layers of 40mm thick night store heater brick hearth, steel drum lined with 2 layers of 40mm night store heater bricks, ceramic fibre insulation, vermiculite concrete, render.
They were part of an old coal bin I think.? This side of the panel will be on the inside, the other side of the panel is a lot better. I'll give them a water blast tomorrow, they should come up good.
Day 1.... Timber Frame built - H4 Pinus Radiata Fence posts, lots of galv coach screws and galv metal brackets.
The word has got out amongst my friends and we are apparently having a Pizza Party for New Years... Nothing like pressure to motivate!!
Found a spot for it in the garden. Need to make a better foundation for the front legs of my base. Will be pouring a solid concrete pad under them for better strength.
Picked up another old Night Store Heater today, that’s 4 heaters in total costing me $12.50NZ. 64 Bricks.... cheaper than $7 each for new fire bricks!!
Brick size is 230x190x40. An awkward size for the top of the oven, I guess I will have to cut them in half. 95mm brick will follow the drum closer I think.
I was planning on doing two layers of bricks under and over the oven, Will this be too thick? Or could I get away with one layer over the top?
My collection of bricks.
Also inside the heaters was this thick Insulation
Pretty horrible stuff... very itchy and lots of fine dust comes out of it. I have to do some research but I hope this will be some sort of high heat insulation I can use on the outside of my oven? It must be able to handle reasonable heat being inside the heater next to the bricks. It's about 25mm thick but I have enough for a couple of layers.
Bring on the weekend... I want to progress some more!!!
I'll be following your build keenly and stealing any ideas for my own build. :twisted:
The vermiculite layer is insulation and, as I understand it, you can not have 'too much' insulation between the thermal mass and the outside. I've seen some builds here use empty bottles in the vermiculite insulation layer, presumably for economy, but I would think that negates to some extent the insulation as glass is a good conductor.
Hi Rich, Instead of a concrete slab, I'd go for aircel type concrete blocks, they will be lighter, and easier to lay, and will add extra insulation, you'd only need a few 4-6 inches of vermicrete to make a flat surface that you can bed your firebricks on. 1 layer does fine for me, and I think 1 layer for the top would be ideal too. Cheers Marcus
Calaf Please steal any ideas you see... I'll be watching your build with interest as well. None of my ideas are original; almost all of them are from other peoples builds.
minesamojito Yes, I'd like to use Aircel Concrete, We only have a few manufactures that make a similar product here in NZ and they haven't been around that long so the products have yet to be ripped down and recycled. So that means I'd have to buy new and I don't know if they would sell such a small quantity. I'll make a few phone calls tomorrow and try to get some... racking my brains at them moment. Concrete pad may have to be used to keep up with my New Year deadline!!
I might use two layers of bricks on the base to store more heat for longer cooking times. There is another Heater selling for $1 tomorrow so I'll grab it... heaps of bricks!!!
Fire clay has proven to be a problem to get hold of, either sold out and not getting any more until next year or never heard of it. Finally found some for a reasonable price. Pick up next week.
Shame about the blocks rich, they're really quite cheap here hence why I used them. Love your hand mixed concrete, looks good and strong and will do the business. Have you sourced a barrel yet? Cheers Marcus
Yeah I almost died when he told me the price of them. But can't dwell!!
Guess they are more expensive here as they are not used in construction has much... We can't build un-reinforced block walls, due the recent events we know they don't like to move and just fall over!! :?
Yeah I made the mix good and strong so hopefully won't have any problems with it. 8 Wheel barrow loads!!! :shock: Doesn't sound much but my body feels like it was more!
Dad has a drum sitting around at his house... So that has been tagged, It has a removable lid on it, so will have to weld that up.
I'm going to try and get the Vermiculite and Health Bricks done during the week. Might do what they call and island hearth...(saw it on another pizza oven website) two or three layers of bricks under the oven and then surround in Vermiculite... I might even put some of that insulation out of the heater under the bricks as well as I have heaps of it. What to try and insulate it as much as possible. Will have to do some research and see what other people have done.
Got another Heater for $1.50NZ last night... so that’s 5 heaters now... I think I have enough now! :roll:
One more question... In the heater there is a thin panel with brittle fabric both side and some sort of crumbly clay, dirt stuff in the middle... Does anyone know what this is? Just wondering if I could use it in my oven some how?
I think it's calcium silicate a great insulator. I had the same in my storage heater and crumbled it up and added it to my vermiculite mix, I thought it might help a little. I also used the blanket over the top of my oven, the more the better as you say. It sounds like you have the market on night storage heaters cornered Rich. Got any plans for all the metal casings? Cheers Marcus
Boxed in a smaller section directly under the oven. Good idea!! Wish I could get hold of those insulated blocks!!
I will have to cut the drum and get it ready before I decide how I'm going to do that?
Might just end up doing the whole hearth... I worked out 1.5 bags should be enough to do the whole slab... How much does that Vermiculite compress when you mix it up with cement and water? Do you get roughly 100L of Vermicrete? Or does it shrink it a bit?