Last brick (well almost)

[Gentcpa]

Hi:

Yeah, the dome is done. It has been cold here in the NE, so I have had a heater in the dome over the last week. Especially as it poured with rain on Monday and for some reason the oven wasn't covered so it was very wet right before the colder weather hit.

Now I just need to finish the chimney transition and some cosmetic details on the arch. The plastic jug is being used as a form for the Duratech anchor which I will mortar in place tomorrow.

Thanks for everyone's advice, I wouldn't have been able to do this without it.

Peels, brush, flour, tomatoes, olive oil and probably most important insulation are all on the way from FornoBravo.

Thanks again

Julian

[gjbingham]

Re: Last brick (well almost)

Julian,
She's gorgeous. Really nice work!
George

[asudavew]

Re: Last brick (well almost)

Yeah. that keystone.. Awesome!

Really nice !

[Ken524]

Re: Last brick (well almost)

Nicely done!! Love the plastic jug.

[Gentcpa]

Re: Last brick (well almost)

Now this is the last "brick". I decided to do something different for the last one. Living in the "granite state" I grabbed one of the granite boulders that I had pulled out of the ground when the ovens foundation footings were dug. Managed to cut it into a nice block and then into the final brick. I finally killed the Harbor Freight 10" blade cutting the granite and switched to a new Home Depot blade. I prefer the HF blade it is thicker and cuts slower but it doesn't flex as much so it runs much truer. I started out the project with a HD blade, and switched to the HF blade early in the project because the HD blade was flexing enough that it developed a dangerous looking harmonic wobble.

The granite ended up being close in color to the fire brick so some of the effect is lost. Still not certain exactly where I am going with the arch for the final finish. However, I get to play with fire next weekend... The final finishing is going to wait until next year as it is really too cold to be messing around with mortar and water. My hose pipe and water buckets were all frozen this morning and the layer of ice on the pool didn't melt during the day. Today I cleaned up all the brick working gear and drained all the outside water pipes.

So one month and 230 odd bricks later it is done.

Thanks for looking


Julian

[asudavew]

Re: Last brick (well almost)

Your avatar...

Is that your finished dome?

I can't seem to find a large picture of it.

And I want to see it!!


How did that vent turn out?

I want to see that too!!

And sorry bout the weather.

But maybe you can keep busy with some curing fires.

[Gentcpa]

Re: Last brick (well almost)

Hi:

I have been building several fires a day. I am starting to get the hang of it. The dome started to turn white in some areas today. I did ok with the newspaper and cardboard fires. I even did ok with twigs. I had trouble when I moved up to bigger stuff. My brother in law gave me some seasoned wood. It may as well been petrified wood as mostly it would just smoulder and smoke out the neighbourhood.

Today I bought some nice hardwood and that burned very well. I had no smoke for most of the burn.

The good news is no dome cracking. The bad news is my arch did crack. Looks like I made a mistake in not allowing enough expansion room for the Duratech anchor.

My Ratek thermometer seems to only go up to 600 degrees. My vent, top three quarters of the dome and portions of the floor were over 600 and white patches were beginning to appear on the dome.

I need to come up with a fix for the expansion issue on the chimney. Any suggestions? I'm thinking about cutting some expansion slots in the anchor.

I have tried to cook in it. I tried steak yesterday, which didn't work out very well due to the petrified wood. Today I searched for something to cook when everything was nice and hot the best I came up with was a bagel with some cheese. At least I played around with a peel.


Thanks for looking


Julian

[Ken524]

Re: Last brick (well almost)

Julian, sorry to hear about the cracks. What part of the anchor expanded? Did the diameter of the bottom that's set in your arch increase?

[Gentcpa]

Re: Last brick (well almost)

Hi Ken:

Yes, the collar is a pretty tight fit in the arch. I didn't anticpate how much that would expand. It cracked pretty early in the firing process. My flue temps are over 600 degrees so it only makes sense that is why the arch cracked and opened up the way it did. Thankfully it is on the outside not on the dome side, so I could potentially repair it if I so choose.

I am thinking about pulling the anchor off tonight and either cutting some slots into it or crimping it so it has some expansion freedom. When I think about it I'm kind of surprised Duratech doesn't crimp it.

[Ken524]

Re: Last brick (well almost)

When I think about it I'm kind of surprised Duratech doesn't crimp it.

While the Duratech system is almost perfect for our ovens, I suspect we are using the the product for an application the engineers didn't anticipate.

The Duratech website lists designed applications: Wood stoves, fireplaces, furnaces, boilers, stoves, ranges, water heaters, or other appliances fueled by wood, coal, oil or gas.

With the exception of "other appliances" the applications listed wouldn't need to worry about a little stainless steel expansion.

I'm curious now... I'll pull my Duratech booklet and see if it mentions expansion.

[Gentcpa]

Re: Last brick (well almost)

I pulled the Duratech anchor of last night. I used some tin snips to cut the collar so it can expand freely. I will see what happens now.

There isn't much I can do about the cracks, but it will be interesting to see if they open up again.

[gjbingham]

Re: Last brick (well almost)

Julian,
Do you have any pictures of the failure that you experienced due to expansion and your modification to the anchor? I'm having trouble visualizing your solution to the Duratech anchor (never having seen one before)
Thanks
George

[Gentcpa]

Re: Last brick (well almost)

No sorry, I should have taken some pictures so everyone could see and hopefully learn from what happened. I thought about it but didn't feel like recording it.

The Duratech anchor has a four bolt flange and a round collar that is supposed to fit into something else. The collar is just flat thin guaged metal that was easy to cut with tin snips. As was previously mentioned I don't think the anchor was designed with this application in mind. It was probably designed as a pass through for ceilings so it was designed for a metal to metal contact. In my situation I built the arch so that the collar was a tight fit which in retrospect was a bit dumb. It had no where to expand and cracked the arch pretty early during the last hot firing. I had flue temps over 600 degrees.

I hopefully fixed it by cutting the collar so that it is more of an individual tab arrangement. We will see if it works.

The crack could have nothing to do with the anchor but I doubt it. The dome has no cracks "yet".

Kind of begs the question of what happens with the angle iron support that is often used in the entrance. It seems to me that dissimilar materials should be avoided if possible. I was originally going to go with a clay flue but after reading about trouble others had with cracking and the clearance that needs to be built around them for a structure I went with the Duratech.

The Duratech from a chimney point of view my flue temp was over 600F while the outside never went over 80F. Just need to rethink clearances for attachment.

Sorry for the book but hopefully someone else learns from this and doesn't make the same mistake.

PS. the crack was big enough to see right through it.

Julian

[sarah h]

Re: Last brick (well almost)

Sorry to hear about your arch and vent woes. I think perhaps I'm experiencing something similar as my chimney pipe has cracked in a straight line from top to bottom - I can't help wondering if it's due to the metal vent on which it's mounted. I have no advice to offer but I'm sure we'll both get past these problems.

Sarah

PS - don't think I ever posted to say I love your granite 'brick'!

[Gentcpa]

Re: Last brick (well almost)

Thanks for the encouragement Sarah. Glad to see you are cooking pizza. I am planning on pizza over the next two days.

Good luck with your flue as well. I guess we are all going through some growing/ design pains.