38" build in southern IL

[kanoer54]

I have been following this site and the forum for several months now. What a great site! Lots of great ideas and comments from everyone. Well, I am ready to jump in to the adventure of building a WFO. However, a brick patio using the ka-chink method to cut bricks is the only brick experience I have. Most of the insulation, brick, IT, etc is in my garage ready to go, so this project will be a challenge. Before i start i have a question for whomever may want to comment.

Some background might also help. Somewhere on one of the threads and photos I checked out a couple months ago i saw a comment about using concrete manhole products to support the oven platform. So I thought, hey, why not? I did some research and found it to be quicker and more cost effective than pouring my own pad, block walls and concrete platform, at least in my area of the country. I have had delivered (a story for another day) on a rainy day a couple weeks ago an 8" thick reinforced concrete footing/foundation slab, a 36" tall manhole structure (5'ID/6'OD) and an 8" thick slab on which to build the oven.

My question is...under the oven vent landing, can I use 6-1/2 inches of fire brick in lieu of 2-1/2 " of fire brick and 4" of ceramic fiber board insulation? The brick is less expensive than board and the board would not get wet and hold water...which could be an issue from what I've read on the forum.

I'll post pics as i get to them. Comments and assistance is always welcome and greatly appreciated.

thanks...jon

[boerwarrior]

Re: 38" build in southern IL

Jon, I'll jump in here.

Welcome to the forum!

Warning: I am still in the process of building my oven so some of my perspective is based on what I've read!

The potential issue you may have is heat being sucked out of the landing.... Of course the landing is going to be much cooler than the inside of the oven so the risk isn't huge. Are you considering a thermal break between the inner and outer arches and floor? If yes, then your approach is probably fine. Just my guess!

My build is here:
http://www.fornobravo.com/forum/f8/3...nia-19283.html

Neil

[kanoer54]

Re: 38" build in southern IL

My thoughts are on a thermal break between the inner arch and the floor. As of now, I was not planning on a thermal break between the inner arch and the vent wall supports. I am planning on using two 2 foot sections of clay tile (8"ID/10"OD) for the vent. Each of these weigh 54 pounds and I am not sure about supporting them on fire brick vent walls which would only be tied in at the front arch.

I'm not real computer savvy. Part of the serf to peasant training I think. I'd post some sketches I drew up but haven't been able to figure out how to attach them to the thread yet. Any help here would also be appreciated.

thanks...jon

[boerwarrior]

Re: 38" build in southern IL

My thoughts are on a thermal break between the inner arch and the floor. As of now, I was not planning on a thermal break between the inner arch and the vent wall supports. I am planning on using two 2 foot sections of clay tile (8"ID/10"OD) for the vent. Each of these weigh 54 pounds and I am not sure about supporting them on fire brick vent walls which would only be tied in at the front arch.

I'm not real computer savvy. Part of the serf to peasant training I think. I'd post some sketches I drew up but haven't been able to figure out how to attach them to the thread yet. Any help here would also be appreciated.

thanks...jon

Jon, I added cast iron brackets as buttressing to the sides of my outer arch. See photo. No experience yet with how they will work but they are bolted into the concrete base with concrete anchors and they feel rock solid - so I am confident.

the easiest way to add photos is:
- save your photos to a directory on your computer. Preferably as a .jpg (jpeg) file
- if the photos are large (many MB) then use editing software to reduce the size down to around the 500kB size - the photo editor that comes with Microsoft Office works fine or you can download free editors off the internet
- click the paperclip icon in the forum editor toolbar (next to the smiley face!)
- Use Browse to find the saved photo in the directory you saved it in previously
- Upload the photo using the "upload" button
- Close the upload window
- You're done!

(if the photo refuses to upload it is normally a sign that it is still too big)

Neil

[kanoer54]

Re: 38" build in southern IL

neil,
thanks for the heads up on the picture downloading. i hope to get it figured out shortly as i do have some sketches and some progress photos of the base to post. as we had yet another night of torrential rains (2.4 inches and still coming down) i may work out in the shop to finish the insulation cut and dry fit and start on brick layout.

jon

[kanoer54]

Re: 38" build in southern IL

oops, apparently i need another cup of coffee. after i submitted my previous post, i realized my sketches still had my old company name. i am recently retired and just picked up an old sketch pad.....i am NOT endorsing any company or anything. my error. won't happen again!!!

[kanoer54]

Re: 38" build in southern IL

now that neil directed me what the paper clip symbol is for i managed to figure out how to post pictures and a couple of my sketches. i probably should have listened to the computer geeks at work when they offered classes. also had some help from my wife who seems to know more about computers than me....thank goodness.

well here are a couple pics a week or so ago the day i got the concrete base slab, manhole pipe and custom top delivered. i spent a lot of time working on the design for the base, the manhole structure and the top. they put in two mats of #4 and #5 rebar 8 inches on center both directions for the base slab and top oven build concrete slab. the manhole structure is 36 inches high 5'ID/6'OD with 6 inch walls and looks like a mickey mouse head when looking down. probably overkill but i almost feel like i could use it for a storm shelter if i just added steel doors.

really antsy to start cutting and laying brick. just need to be patient about getting some less rainy weather i guess

[Gulf]

Re: 38" build in southern IL

That is a very interesting build that you've started there, Jon! I do like the base.
From the sketch, it looks like you are going to have a 6" thick concrete enclosure?. Wow!!....that's heavy duty with the emphasis on heavy. I am probably not reading the plans correctly, but it looks like the structural part of the dome will sit directly on the concrete hearth. Please, correct me if I am wrong, because that would be a mistake. There are a couple more things that concern me a little, but the main point that I/we want to bring home is that the dome and floor need to be sitting on and in a "cacoon" of insulation.

Again, I may be reading the plans wrong, just say'n .

[SCChris]

Re: 38" build in southern IL

the main point that I/we want to bring home is that the dome and floor need to be sitting on and in a "cacoon" of insulation.

Again, I may be reading the plans wrong, just say'n .

Ditto what Gulf is saying.. Insulation isn't everything, but if you search around you'll find several "help" posts from people who didn't have insulation.. Floor insulation is most often overlooked in other web plans and getting the floor hot and keeping it hot is really an effort without. I have 2 inches of rigid CalSil insulation under the floor bricks and my oven is surrounded with as much insulation as I could fit within the oven house, I have never regretted maximizing my insulation. When I cook pizza for dinner and close the door 2 days later the oven interior is still at 375F. I can always open things up and cool things down and this really opens the door for a lot of really fine cooking..

Welcome to the forum!

Chris

[kanoer54]

Re: 38" build in southern IL

gulf,
thanks for noting that. you and others are thinking, what kind of nut wants to build a dome and then stick it in a concrete manhole structure. i guess i was inspired by a photo i saw on the forum in january.

i initially drew it that way not knowing any better (serf dumbness!) but then did figure out, after following other builds pics, that the dome has to sit on insulation. i have since corrected that and plan on having two 2" layers of 8# ceramic fiber board under the entire dome and floor. nice catch as i learned a lot from the forum after i drew the sketch.

i was mainly trying to see if i could fit it all in a 50"ID/60"OD structure, including a clay tile flue but finally determined after beating my head against the wall, i needed a 5'ID/6'OD structure or the flue would have to go outside the manhole structure. thus the larger structure,

to show my serf ignorance, i had even thought if one layer of brick floor is good, two may be better to provide more thermal mass. i decided to switch that around once a kept reading the forum.

since you jumped in and are a much, much higher pay grade, am i correct that i should use sand to level up the insulation board over any slight (and i mean slight, less than 1/32") irregularities? how about between the insulation and the hearth floor? will the fine masons sand be satisfactory? i was thinking the washed river sand may be too course. any thoughts from you or anyone?

and then speaking of hearth floor, would there be any issues with using 12"x12"x2-1/2" medium duty fire bricks set on a diagonal pattern for the floor in lieu of the medium duty 9"x4-1/2"x2-1/2" fire brick?

one thing not shown on the sketches is that i do plan on filling the whole space around the dome with vermiculite for insulation.

gulf, you mentioned in your post there are a couple more things. could you elaborate on these please!!!. i'd rather address any concerns now than later. as i go along this build you'll find i am pretty anal about doing things right the first time. i hate tearing things down when more planning and thought would have made the project a lot easier.

lots to learn on my part.
jon

[kanoer54]

Re: 38" build in southern IL

chris,

thanks for the input. i guess i was typing (not very quick at this typing stuff) when your post came over. thanks for the input. i have learned a lot from everyone and still have LOTS more to learn. i'll even post my mistake pictures (embarrassingly though and hopefully not too many) so others can learn.

i remember reading a thread about 2 ways not to build the oven door. how nice of him to share his mistakes so we can all learn.
thanks again.
jon

[UtahBeehiver]

Re: 38" build in southern IL

Jon,

Gulf's oven is not called the Queen for nuttin, it is huge. Listen to Gulf he has been around the block.

On the fire brick floor, nothing wrong with 12 x12 in fact less seams to worry about. You can mix fire clay and fine sand in a 50/50 ratio for leveling. I made a slurry and used a notched trowel to level my first layer of insulation on the hearth. I did not have to use anything after that. Some people have used a dry version as well.

Keep sending the pics, that is one unique base.

[SCChris]

Re: 38" build in southern IL

Jon, if you decide to use something as a leveler be careful. If you're not very careful the insulating board will suck the moisture right out of the leveler before you have a chance to settle it in, and I mean you had better be lightning fast. I recommend using something dry rather than wet because you'd have time to settle it. The rigid insulation will be dead flat and unless your 12 by 12 bricks need something to make them flat, I'd just set them where you need them. In the end ash will fill the small gaps between the 12 by 12 tiles and they'll settle in just fine.

Best to you!

Chris

[kanoer54]

Re: 38" build in southern IL

thanks all. i've been following a bunch of you guys build and have to say they look great. i wonder how many of you are really professional masons but not letting on to us? sure look professional.

if it stops raining here, i may be able to start laying insulation and oven floor. tarps and plastic are close by just in case the weather man is incorrect.

???: i think i will go with dry sand mix and see how that works. is masonry sand or river sand the right thing to use ?


jon

[Gulf]

Re: 38" build in southern IL

Original quote by Kanoer54

you and others are thinking what kind of nut wants to build a dome and then stick it in a concrete manhole structure

By no means Jon,
I do like you base. It is very innovative and I can see that it would be fun to work with for a final finish. I'm looking forward to see how you do this. Also, I can see that the manhole has saved you a lot of time, already.

Original quote by Kanoer54

you mentioned in your post there are a couple more things. could you elaborate on these please!!!

You've cleared all of that up by your responses except, the thickness of (what I interpret) as a 6" concrete enclosure? I think that your base is fine for most anything (and more) than most of us would put on top of it. But, it is my concern, that if your footing is not resting on bedrock, you might not want to get it too top heavy. If you want a concrete enclosure, I think think 1 and 1/2" to 2" panels is enough. One leaning tower of Pizza is enough .

Original quote by UtahBeehiver

Gulf's oven is ..., it is huge

Thank's Russell.

Jon, my oven is on the portly side. But, if someone can take the time to dissect it they will find lots of weight saving steps (done to off set some of my eccentricities) . Each one (I think) combined weight saving with more insulation.

I think that you now have enough interest from the forum to keep you out of trouble and especially, since that you have done a lot more research since you original sketches. Keep the pics and the intentions for each of your next steps coming.

From what I have seen so far, I am sure that your's, is going to be one an epic build .