Building in Central Florida, Question about insulation beneath cooking floor

[glowthb]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Thanks Drake.

[DrakeRemoray]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Looks Great! Now the fun part begins! Cooking! I used a vanes approach and had almost the opposite problem that you had, not enough mortar on the inside joints. I had to go in an point the inside of the oven. I think if I ever build another, I will use the indespensible tool instead of the vanes, but that said, my oven is extremely functional if not as pretty inside as some of the newer ones! Enjoy (from a fomer Floridian...Go Gators!)

Drake

[glowthb]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Dino...Thank you for your comments. I have to say it has been a very enjoyable project. A bit of an obession at this point but a rather good one I think.

[Dino_Pizza]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Nice job! I like your angled vent and the way you put the anchor plate on. It will draw smoke well, you'll have no worries there. You're right, use the heat-stop and just point it in where you need it. So there's a little mortar over the edges, your brick work looks pretty sharp.
Keep up the good work,
-Dino

[glowthb]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Neil,

True...I could have used a few more vanes. But I did not expect to hit that point until the vanes were close enough to bridge the bricks.

The chopstick idea is a good one. I agree the styrofoam overall is a proven technique but with some things to consider. I am pleased with their performance overall and think I still prefer them to the indispensible tool...at least for me. Particularly when I get impatient and want to get more done at a single sitting. The indispensible tool certainly has proven results of incredible quality. I am amazed at some of the projects on here and enjoy the dialogue.

[Neil2]

Re: Building in Central Florida, Question about insulation beneath cooking floor

"If your bricks are sliding and there is not a vane to catch it, "

I bought a package of cheap chopsticks and cut them up to bridge between the Styrofoam vanes at that point. They can be pressed into the styrofoam to maintain the exact shape. This also allows some access to the inside joint as you go for cleaning up the mortar.

I'm a great believer in he stryrofoam vane/formwork approach. Once set up, there is no guesswork - you know the dome shape is going to come out exactly as designed.

I can't see from your photos, but I also cut sizable 6-8 inch half circle "mouse holes" in the bottoms of the vanes to facilitate air circulation (and dropped tool retrieval).

[efleifel]

Re: Building in Central Florida, Question about insulation beneath cooking floor

WOW, You have done a lot, and it does looks good, you are just being mosdest. I did nothing this weekend.
I agree it did get sloppier as we close the dome. I also found that I had to go in and mortar the gaps from the inside.
Cheers

Eddie

[glowthb]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Not the prettiest entrance but will be enclosed anyway in a gable house design.

[glowthb]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Well I got the dome closed this weekend. As the opening got smaller, the brick work got sloppier but I am sure the Heatstop50 will compensate for it, okay, fingers crossed a bit. It seems very solid.

As you can see, another issue with the styrofoam ribs is you cannot clean off the excess mortar as you go so there is some clean-up work to get done next weekend. Thank goodness for a skinny 18 year old son. He is already on task to climb in and clean it up.

To add some additional "grab" on the Duratch plate, I used some half inch "metal cloth" bolted around the four sides of the plate to grab into the mortar.

[efleifel]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Hi,

I can see the 3 pictures now but not in the previous posts. Looks very good.
I had to do the same thing when I was using the styrofoam, I used card- board to hold the bricks as well. Unfortuantely I could not do anything with the oven today, I was planning to build the front arch and the vent this weekend, but the weather was windy, and then started raining. Hopefully next weekend.
Cheers

Eddie

[glowthb]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Efleifel...are they not showing on previous pages?

Here are the latest as I am getting (hoping) to close the dome.

A couple of lessons learned to relay to someone taking this on:

1. Bricks cut in half are heavy. Your ability to keep them from sliding with fresh mortar gets more difficult as the angle increases.

2. Styrofoam vanes are nice, but make sure you have enough to provide support to help with the issue above.

3. Shimming Bricks from the inside quickly causes problems getting off the gradual dome igloo you are "curving" in to shape.

Recommendations:

1. Styrofoam vanes are fine but get some cardboard to cover the top half or so?the area when your bricks start hitting more than 55 or so degrees.
2. At that same point start considering cutting those half bricks in half so the mortar is not pulling all the weight.
3. Avoid shimming from the inside. If your bricks are sliding and there is not a vane to catch it, it is time evenly cover those vanes with cardboard. This helps keep the uniformity you are looking for. Shims may help in that one spot, but the next course may be off.
4. Finally, as you get to the top, the need for custom cutting bricks to fit is necessary. Using squares to form a circle gets harder as that circle gets smaller.

Others may not have experienced the above but something to consider as you move forward.

[efleifel]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Good morning glowthb,

Please excuse my ignorance, but I cannot find the link or photos of your oven, but reading some of the posts above, they seem to have seen some.
Cheers

Eddie

[glowthb]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Neil,

Thank you for reading through and providing input. It is reassuring to know it is on track to optimal engineering standards.

I agree, narrowing opening should not be an issue if necessary. Going wider however...another story.

Hopefully I should get to the dome this week...under the lights.

Thanks again.

[Neil2]

Re: Building in Central Florida, Question about insulation beneath cooking floor

The "magic" ratio for door height to inside dome height is 63% which is pretty much what you have achieved.

Your height to radius ratio is about 90% which is in the optimum range for an elliptical oven.

I still think your door opening is a bit wider than typical, but this is something that is very easy to modify if you find you are having problems with it once you get your oven working.

[glowthb]

Re: Building in Central Florida, Question about insulation beneath cooking floor

Minor correction needed here regarding number of bricks at the oven opening. I actually added a 6th course to the height of the opening. The fire bricks here in Central Florida, for what ever reason, are coming in at +/- 2.25 inches high and not 2.5. The top of the 5th brick is right at 12 inches if you are looking at the photo with the level across the top.