36inch build in Redlands

[cobblerdave]

Re: 36inch build in Redlands

Gudday
I went back and checked out your brick. There plenty big enough.
Remember your building 2 of the strongest types of building on the planet the dome and the arch. Both of which depend of gravity for there strength. You want to be able to lock both the dome and the arch in together so cutting a slip of the arch is a good thing.
Regards dave

[stevo70]

Re: 36inch build in Redlands

Yes I can understand why you would cut the arch on an angle but in my case, I have ended up with the inner arch a little narrow, (75mm front to back) so don't really want to take any more meat out of it to keep it as strong as possible. It will be the back edge of the chimney which I want to start off with bricks going about a foot high so even more weight. Might have to cut some strange angles on the dome bricks that come around that part. I actually did draw it up on cardboard and used a piece of string to see where I would end up but the more I looked at it, the more it confused me.

[stevo70]

Re: 36inch build in Redlands

Hi Stevo

It may just be the photo [optical illusion] and the angle but the Brick in your IT looks like it is around the wrong way.

The bricks I acquired are a strange size. Have cut them into 4 which still gives me the 4.5" wall thickness but it is a small brick. Could leave them in halves if I want to but the arch looks neater with smaller bricks.

[cobblerdave]

Re: 36inch build in Redlands

Gudday
Draw a mockup of you oven dome full size showing full thickness of brick on large bit of cardboard. Make one of the floor showing the brick as well. You can then play with some bricks with it. You see very quickly why davids said to cut an angle in the back of your arch
Regards dave

[oasiscdm]

Re: 36inch build in Redlands

Hi Stevo

It may just be the photo [optical illusion] and the angle but the Brick in your IT looks like it is around the wrong way.

[stevo70]

Re: 36inch build in Redlands

Thanks Colin and David, Good advice. Do you think my arch is in the correct position as far as being not too far in and not too far out?

[oasiscdm]

Re: 36inch build in Redlands

Stevo

David's right, on both counts.

[david s]

Re: 36inch build in Redlands

If it was mine I'd be tapering those arch bricks and trimming about 10 mm off the bottom of the arch form, then place some wedges under it so the form can be dropped. Otherwise you'll have difficulty getting the form out and risk damaging your newly laid arch.

[stevo70]

Re: 36inch build in Redlands

How am I looking for inner arch location? Its all just mocked up for now but seems like an important step and I want to get it right before I cut the floor tiles to fit inside.

[david s]

Re: 36inch build in Redlands

I don't bother covering it. The cardboard itself prevents almost all material from falling in the space. It fills with wood ash anyway.

[stevo70]

Re: 36inch build in Redlands

I prefer using a single layer of corrugated cardboard for this space. It is about the right thickness required and burns away easier.

Ok so I will want to leave a gap between the floor tiles and the first course of about the width of a piece of cardboard? or maybe about 3mm? Cover it while constructing to keep cement etc out of there?

[david s]

Re: 36inch build in Redlands

[QUOTE=
Run a bit of tape around the space between the dome and hearth so it doesn't fill with mortar as the build progresses for the same reason.

Regards dave[/QUOTE]

I prefer using a single layer of corrugated cardboard for this space. It is about the right thickness required and burns away easier.

[stevo70]

Re: 36inch build in Redlands

Thanks Dave, Makes sense what you say about the soldier course but unfortunately I have already committed and cut my first course. Might not be as bad as they are a weird shaped brick cut in half which makes them shorter than a normal fire brick. They are only 160mm tall and with the angles cut to support the second course makes them even shorter might be ok?

[cobblerdave]

Re: 36inch build in Redlands

Gudday
Don't ever be reluctant to ask ,the plans arnt everything.
On the question of mortaring down the first ring of brick that's a No. The domes best to be left to expand and contract separately to the rest.
Run a bit of tape around the space between the dome and hearth so it doesn't fill with mortar as the build progresses for the same reason.
There has been a lot of discussion over soilder courses over time, but if you use one it will require buttressing of some form at least an inch of mortar around it.
My own build has a soilder course, but I err to side of caution as you can achieve a stronger constructin with bricks layed on the flat

Regards dave

[stevo70]

Re: 36inch build in Redlands

Good tools do make good job. Looks like you can weld. Good luck on your build.

Thanks yes fortunately I can weld and think I'll stick to that after this oven is built. A professional brickie would have stories to tell for weeks if he saw me building my arch yesterday. Got there in the end and it is reasonable. Harder than it looks. Also layed out the insulating bricks precisely and built up the floor height to them with mortared down commons. Left some channels for weep hole drainage. Should work out ok. First course to go down now. Will arrange them on their ends and I have cut a slice off each one to give the second course a more angled surface to sit on rather than flat. This question might have been asked a thousand times but is it best to mortar down the first course or leave it just sitting on the insulation bricks? Downloaded instructions don't really mention it. My floor will be cut to fit inside the first "soldier" course.