Karangi Dude's 48inch Oven

[Knackers]

Re: Karangi Dude's 48inch Oven

There were some pretty fancy cuts to be made but I am sure the transition will be a lot easier when I get to the 7,8 & 9 chains let's see if my plan works.
Cheers Doug

Sorry for bringing up an old post of yours. I have noticed that your angles get less as you go up the arch to allow for the decreased size of the dome the higher you go. Did you work out each angle? if so how did you do it? or was it an estimate of whay you may need?
I will definatly refer to you build once we move & I do my build.

Thanks in advance
Mike

[Karangi Dude]

Re: Karangi Dude's 48inch Oven

Hey Mike,
When I cut the Door Arch I basically started with the first brick next to the entrance and used that shape for for the first few rows (note that there is a left and right angle for each side of the arch) and then extended the width of the bricks the further I went up. I suppose you could say I just estimated the angle of the oven curve. If I was to build another oven I would build the arch the same time as I was building the oven row by row, that way you could make adjustments as you go. You would also have to make sure that you keep the mortar back from the form so that when you take the form out it will be nice and clean and then you could piont it up later. BTW this design was for a full curved arch I am not sure if would work with a straight sided arch. My angles were pretty close but I did need to use a couple of small splits to fill some gaps. I think I needed to extend the transition bricks even further than I did. Also this design may not work if you were to use a soldier course, I can not understand why peolple seem to use a soldier course. Notice in the pic below the first brick on each side of the entrance that's the shape you need to start with. Mike also note that the cut face of the arch brick needs to be 115mm or half a brick wide so that the dome bricks will fit neatly see second pick.

Regards Doug

[cobblerdave]

Re: Karangi Dude's 48inch Oven

Dear Doug
Great build... been watching your progress with great interest, glad to hear you have cooler wheather I couldn't imagine building mine in the heat!!
and Dear Mike
Just to offer a differnt bent. I have used a soldier course for the main reason being it that it gives you more room against the sides as the domes curve starts much higher. I'm really sure that doug's method ( and his constuction skills)he could have pulled the same thing off with a soldier course...the only real difference his arch would have to have a straight section before starting the curve.
Regards Cobbler Dave

[Karangi Dude]

Re: Karangi Dude's 48inch Oven

Hey Dave,

Thanks for the kind words.
Please don't get me wrong, I just think that the very sides of the oven are probably too far away from the heat source. That is one of the reasons I have gone for a slightly bigger oven, I should not need to use the sides of the oven close to the walls. Also the dome bricks just fall in place with the door arch as there is no transition at the top of the soldier course.
If you do want straight sides on your dome you can just lay 2 to 3 courses before you start the dome curve that way you don't need to cut the angles at the top of the soldier course.
Just my take on it.

Cheers Doug

[cobblerdave]

Re: Karangi Dude's 48inch Oven

Doug
solved...
Regards Dave

[Knackers]

Re: Karangi Dude's 48inch Oven

Hey Doug,
thanks for the explaination & pics. that clears alot of things up for me.
I do like your build, Very clean & neat job.

[Mitchamus]

Re: Karangi Dude's 48inch Oven

great job! I'll be following this one from now on..

[Karangi Dude]

Re: Karangi Dude's 48inch Oven

My heart goes out to all Kiwi's devestated by the earthquake in Christchurch NZ.

I was going to post some pics of my oven, but I might just wait untill later.

Kind Regards Doug

[Karangi Dude]

Re: Karangi Dude's 48inch Oven

It's closing up 11th and 12th course now complete.
I had to improvise with a disk on a stand that I lifted up with a jack that worked really well for the 12th chain.
I set one brick in place using the dome guage and let the mortar set over night. I lifted the disk into place then used the disk to rest each brick on for the right height. To get the right angle I marked a spacer at the front of the fixed brick, and then used the spacer to set the angle for the rest of the course. To help the bricks hang on I ground 3 small grooves in the previous course. I will need to piont up inside later.
One chain left and then the key.

Doug

[OscarA]

Re: Karangi Dude's 48inch Oven

You're a clever man Doug, I have been thinking how I'm going to close my dome in the next week or so but unfortunately I don't have a jack that's suitable to do it your way.
Might just have to make a temp stand and build it up as required.
I'm about to go and cut more bricks hopefully I can get the 5 chain done tonight.

[Karangi Dude]

Re: Karangi Dude's 48inch Oven

Thanks Oscar,
You don't need to use a special jack any car jack would do (you need to be carefull not to knock of the bricks that you are pushing against) I used the jack from my Landrover, it was good because I could lift the stand ever so gently bit by bit.
If you don't have a suitable jack just wedge it up with wedges. The reason I used my jack is it is a long reach into the centre of my 1200mm oven to be placing wedges.
When it comes to the next course you need to cut a smaller disk to suit that course.
I made the disk about 2mm bigger the hole and tried to get it tight up against the last course of bricks.

Cheers Doug

[Jayson]

Re: Karangi Dude's 48inch Oven

Doug, this is a brilliant approach. Any other suggestions or advice for those of us thinking of using the same method. Anything you would do differently with the jack method. I think I will do it the same way and just wondered if there was anything else to consider before setting up the same way. I'm fast approaching the top rows.

[Karangi Dude]

Re: Karangi Dude's 48inch Oven

Hey Jayson,
Thanks for your kind words.
The jack thing came about when I was thinking of way to make a mini acroh prop. Basicaly I made a stand but then I needed a way of lifting the stand and disk into place so I simply put a brace at the right height for a jack to slip under and lift the last 10/20mm. Jayson first I made the stand and disk as one piece only to find out it would not fit through the door arch. So I then made the disk and stand as separate pieces, I attached a simple handle to hold the disk up, I held the disk in place while my wife gently cranked the jack until it just nipped the disk to the underside of the previous course of bricks. I then unscrewed the handle and laid the next course.

Regards Doug

[Jayson]

Re: Karangi Dude's 48inch Oven

Doug mate, it's a cracker! Thanks for the extra photos. So basically the disc size doesn't have to be perfect because it's not going through the hole. It just has to be a firm fit just the edge of the last course and the you use a shim/wedge to set the angle. Do I have it right?

[Karangi Dude]

Re: Karangi Dude's 48inch Oven

Yes Jayson,
What I did was measure the diameter of the last course add a couple of mm, tried it for size, it needs to fit as flush with the bottom of the last course as possible that way there won't be any steps between the courses.

Regards Doug