can the dome arch be mortered to the chimney arch ?

[Gulf]

Re: can the dome arch be mortered to the chimney arch ?

.........But what should I use to seal the inside arch to the outside arch on the bottom of these two .?? I have a 1 inch overlap unlike yours where you placed it above the 1st arch .. It is a 1/4 inch space .. sealant or do I pack it with gasket material Looks like you used the black sealant for your whole closer.. ......

I did use gasket material to pack the space. Mine is an L shaped joint. If I had it to do again, I would not notch the outside arch brick for the break. I would just overlap it with a space outside the inner arch.





I did seal over the joint inside the flu entry, but I wouldn't do that again. I speant a considerable amount of time cleaning that mess out of my oven. Afterward, I used an artists brush to seal the rope fibers. I used a slurry of Type-N masonry cement and fireclay. Actually, the fireclay was the fines colected from my wet saw.

I think that 3/8th " rope is as thick as you could place in the 1/4" joint. I would use the rope for the final pass inside the flu entry, if you can find it. For the rest of the gap, I would use strips cut from one end of the cf blanket. That would be cheaper that buying enough rope to fill the entire gap. I used a sharp utility knife and a metal straight edge for cutting the blanket. A framing square works great for a straight edge. Just place a piece of plywood or a 2X4 directly under the cut. Press down firmly on the square and cut. You can use a good pair of scissors, but they won't be a good for very long .

[merlyn]

Re: can the dome arch be mortered to the chimney arch ?

thanks I will use the rope and I have some heat stop 50 left over, to seal the rope for the inside .. .. I`ll use the rutland for the top ..

Iv`e just posted 3 new pics in the photo gallery ..

Not nearly as intricate as your incredible oven but so far so good .. Iv`e referred to your photos countless times for information ,enthusiasm .. Thank you for your posts and help ..

[Gulf]

Re: can the dome arch be mortered to the chimney arch ?

Thanks, and you are very welcome, Merlyn.

I see that you have been attained the rank of Peasant on the forum. I am not sure if it was a coincidence but, my attempts at posting pics started working at that same time.

Almost finished! and no build thread .



Your oven looks great beside your fireplace . I took the liberty of linking this one back from the photogallery. The rest, are on you .

[Les]

Re: can the dome arch be mortered to the chimney arch ?

Sorry, but I disagree w/Les. You do get significant heat loss by connecting the arches and the hearth bricks w/out a thermal break. Enough to make a huge difference? Probably not. Think about it. You do all the other work designed to retain heat, then have both your floor and arches sucking the heat right out. You build a door to retain the heat, then have it sucked right out under and around the door. It's a simple thing to do and in fact does make a difference. Personally, knowing what I do now about it, I would never build another oven w/out thermal breaks. But, to each his/her own, I say.

NC, can you post your numbers? It would be interesting to see where the your hearth is after 48 / 72 hours. If there is a solid benefit then it should be incorporated into the PDF plans. From what we have seen, really doesn't make a big difference (if any). Insulation above and below appears to be the ticket.
In case it was missed I did a little test. For the record these are not strike anywhere matches
https://www.youtube.com/edit?video_i...m-upload_owner

[stonecutter]

Re: can the dome arch be mortered to the chimney arch ?

NC, can you post your numbers? It would be interesting to see where the your hearth is after 48 / 72 hours. If there is a solid benefit then it should be incorporated into the PDF plans. From what we have seen, really doesn't make a big difference (if any). Insulation above and below appears to be the ticket.
In case it was missed I did a little test. For the record these are not strike anywhere matches
https://www.youtube.com/edit?video_i...m-upload_owner

That link opened up three videos I shot. Were is the test you did?

[NCMan]

Re: can the dome arch be mortered to the chimney arch ?

NC, can you post your numbers? It would be interesting to see where the your hearth is after 48 / 72 hours. If there is a solid benefit then it should be incorporated into the PDF plans. From what we have seen, really doesn't make a big difference (if any). Insulation above and below appears to be the ticket.
In case it was missed I did a little test. For the record these are not strike anywhere matches
https://www.youtube.com/edit?video_i...m-upload_owner

I never mentioned me having done any tests. I stated my opinion based on many factors. I believe Gulf just recently posted photos of his using his infra red unit on his oven on each side of his hearth heat break. I believe his photos speak for themselves. I have done lots of research, both on here and mostly on the web. I've met with a man who builds ovens for a living (I think for 27 years) and is a FB Dealer, seen one of his ovens at work(w/three separate heat breaks, etc.) I can go on and on. No one will ever convince me that they are not the way to go. Nor could anyone ever convince me that an oven retains heat just as well w/out them. That, in my opinion, w/all factors being equal, is impossible. This has been debated alot on here, also. There are multiple positives to them (thermal breaks, expansion joint, isolation joint, etc.) and not one significant negative that I can think of, other than perhaps a small expense and perhaps a tad more work. If doing a few minor things to maximize heat retention(remember there are other positives w/them, also) matters to a builder, I recommend using them. If it doesn't matter or a builder disputes all this, then don't. All my 2?.

[Gulf]

Re: can the dome arch be mortered to the chimney arch ?

Funny, just a few minutes ago, I responded to a question on a friend's thread over on a BBQ forum that I frequent.

..................A heatbreak (thermal break) is a small gap separating the cooking chamber of the oven from the entry and flu. Like Ryan said "My inner arch and floor, which will get heat from the fire, can transfer heat through the brick to my outer arch and floor landing." The gap between them is packed with insulation. It can help stop some of the heat loss from the oven, same as the under floor and dome insulation. Since it is not as thick those insulated layers, a thermal break's importance can be debatable.

Their importance depends a lot on what someone wants out of their WFO. Will it be fired only occasionaly, weekly, or used several days a week?

If it is mostly pizza, a heatbreak is not necessary. For pizza, a live fire is going all the time. The insulated door is left off, radiational heat is escaping, and will heat up those areas anyway.

If someone is mostly interested in baking bread, and wanting to retain that heat for multiple batches. Then a heatbreak may become a little more important.

If someome is interested in baking mostly, and they live in an area where wood is expensive, then a heatbreak may become a lot more important. More/better insulation translates in to a more efficeint oven (less wood and longer heat retention for more cooking on a single firing).

It all boils down to what the oven will be used for mostly and the availabilty of wood. You also might want to consider the availabilty of wood in the near future. IE: I'm young, I can easily gather it now but, what about when I get a few years older? And, I can easily afford to buy a load of wood now, but what about a few years later when I am on a fixed income?

Having said all that: A heatbreak adds a little more difficulty to the build. They are only a recent addition to a thousands of years old technology, that has worked great for all those years without them. For the average owner, a WFO without heatbreaks, that is moderately insulated under the floor and over the dome will be enough.............. For now :smile:

Oven insulation and heatbreaks are too difficult to retrofit later, though. So, the time to decide is in when you are researching your build. I hope that my post doesn't scare anyone off. WFO' s are hell of a lot of fun to build and even more fun to cook in afterward.............[/QUOTE]

The debate goes on, but that is what makes FB so great .

[Les]

Re: can the dome arch be mortered to the chimney arch ?

That link opened up three videos I shot. Were is the test you did?

Stone, I don't understand why it isn't working. I clicked on the thread in you post and it took me to the video.

[Les]

Re: can the dome arch be mortered to the chimney arch ?

The debate goes on, but that is what makes FB so great .

Gulf we are in agreement - I am just asking (begging) for people to post their numbers. If I can put my finger one inch away from a brick that ignites a match, should I really be worried about heat loss? If we can get the data that supports a heat break I am sure James will get it into the plans. This will only help the future builders - I am totally satisfied cooking on day three without a heat break. As a side note; I remember working at Lockheed and they had a video of the space shuttle tiles - it was white hot but the guy could hold it in his fingers, kinda like fire brick

[cobblerdave]

Re: can the dome arch be mortered to the chimney arch ?

G'day
I'm in agreement with Les an oven without a heartbreak is still a great oven. Yes my oven will cook for days if I do wish. An insulated oven top and base with an insulated door will do that. You can only take out what heat you put in though.
I often run my oven still black and don't believe in taking to pizza temp just to wait so it cool enough to bake!
I believe we can sometimes shame people into building heartbreaks into their ovens for no great gain. We can run the risk of discouraging people from building ovens at all.
I recon the plans should never change as they are both an achievable and efficient working oven plan. This is the base line.
My 2 cents
Regards dave

[stonecutter]

Re: can the dome arch be mortered to the chimney arch ?

Stone, I don't understand why it isn't working. I clicked on the thread in you post and it took me to the video.

Weird. Maybe it's the type of link...like if you've uploaded a video yourself, the link takes you to your page?

[Greenman]

Re: can the dome arch be mortered to the chimney arch ?

I agree with Dave. I built a heat break into my oven and am sure it works but I am sure it would work without as well. It is just a matter of efficiency.

The base home build is about hammers and bolsters and the basic plans. From there it progresses in stages to precision cut bricks, heat breaks and flared entry galleries and all the rest from there.

We have the privilege of sharing it all here, from the exquisite to the rustic and some just rough but they all work to their own level.

Mine fits the middle ground and I am happy with it. I have built 2 more for other people and they are happy with theirs and each is better than the last in one way or another but they all are working ovens. No profit, just wanted to share the joy of the things.

Never be happy with one.

[Gulf]

Re: can the dome arch be mortered to the chimney arch ?

Gulf we are in agreement - I am just asking (begging) for people to post their numbers. If I can put my finger one inch away from a brick that ignites a match, should I really be worried about heat loss? If we can get the data that supports a heat break I am sure James will get it into the plans. This will only help the future builders - I am totally satisfied cooking on day three without a heat break. As a side note; I remember working at Lockheed and they had a video of the space shuttle tiles - it was white hot but the guy could hold it in his fingers, kinda like fire brick

Les,

I don't think that mine or anyone else's numbers will make a rat's as of difference. That is, until someone builds two identical ovens (one with, and one without heatbreaks, in a very close proximity to each other). If that is ever done, I will surely be a believer. One way or the other .

Until then, I have to go with my gut instinct, which leads me to believe that, at the very least,..........they help .

[SevenAcre]

Re: can the dome arch be mortered to the chimney arch ?

Mine seems to work, but more importantly I like the way it looks. Honestly, while building the oven it was rush, rush, rush. Now that it's done and I have all the time in the world to cook, I know I could have spent longer building. In other words, put it in now so you don't wonder if you should have later. Just the fact that you are thinking/reading so much about it now means you'll most likely regret it if you don't

I just pulled my door and took these pictures. Fired the oven 3pm yesterday and cleared the dome for pizza. Last stick of oak went in around 4:30. Door went on around 8pm. Cooked a 2.5lb Tri-tip before work for lunch (around 7am), and my wife did chicken for dinner around 11am. Door's been on since. It's now 8pm on day two, and I have a solid 350 remaining in the oven.

Generally, I run 1-2 hundred degrees difference directly over the break. The temps drop considerably every inch away from the break, and the difference is more when first firing (naturally), and for some reason when the oven is really roaring.

-J