Pompeii started in San Jose

[UtahBeehiver]

If you go with a 4 x 8 inch vent, you need to make a smooth transition at the throat of the anchor plate adapter so you have a full 6" round opening and not to have a restriction right at the brick to chimney transition. Smoke takes the path of least resistant.

[SteveB48]

I hope to attach the chimney plate this evening. I'd like to use a sealant between the plate and brick in addition to the masonry anchors. What sort of temperature rating do i need? I'm trying to find something at Home Depot or Lowes.


thanks,
Steve

[david s]

The highest rating high temp silicon I can find is Permatex Ultra Copper, any other type of non silicon goo I've found to go hard and brittle.The oven gets pretty hot in that position and will really test the silicon. If using masonry anchors make sure you use stainless ones, anything else will be corroded by the heat.

[Larry P]

I used something called "high heat mortar," black stuff in a caulk tube from Lowe's or Home Depot. Indeed it cured hard as a rock. I was useful to take up gaps between the plate and the brick, but with that and 4 anchors the plate could still flex quite a bit. I wasn't 100% happy with this. When I rendered the dome, I filled above the plate with surface bonding cement and it's solid now. 50mph winds and no visible deflection of the chimney. Between Home Depot, Lowe's, and OSH, your selection will be very limited. You'll find 2-3 high-heat products total.

[SteveB48]

Thanks Larry. Lowes and Home Depot don't seem to carry that in the store at least over here. It looks like that's rated for 2000 degrees. Does it really need that kind of temperature rating? The Permatex Ultra Copper is rated for 700. I can find Permatex RTV Red at OSH. According to Permatex's web site, that's rated for 650.

[UtahBeehiver]

You can easily get to those higher temps especially if you start a fire in the vent chamber to start drafting. I used Uni-Extreme, good to 2600 F but it is hard to find and expensive. Some people have used Kawool caulk, runs about 20 bucks a tube good to 2000 F plus. These products you do not find at the big box stores and typically available at refractory suppliers, IE brick, blanket, CF board. You spend hundreds of dollars to get to this point, don't scrimp here.

[SteveB48]

I have no interest in going cheap,. especially with something that I may not be able to get to after the stucco is on. I've ordered DAP Silicate Cement Black from Granger. I believe is what Larry has and the specs say 2000 degrees. I'm going to start my drying fires on Saturday so I'll bolt down the chimney without sealant and then reinstall it on Monday when this arrives. I plan on having insulation but not stucco at that point.

Steve
DAP Silicate Cement Black

[Larry P]

Sorry I was mistaken where I bought this - turns out it was Amazon:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

I think I have a spare tube, if you want it.

[SteveB48]

Thanks Larry. I have some on order.

The first fire is burning! Ok the first fire went out rather quickly. The second fire is burning. Just over 200 at the top of the dome. I'm going to need some practice with my firing skills. This is different than a locomotive!

[Larry P]

Not easy to control a fire at 200º. It takes a lot of attention, and it's almost impossible to not overshoot.

I'm smoking salmon today, and debating if I should use the oven or the BGE. If the oven was cooling through the 180º range, I think it would be a no-brainer, but I'd have to heat it up *slightly* right now to get it at the right temp, which I think is probably not possible.

[SteveB48]

200º just happened to be the temp when I posted. Most of the 8 hours was spent between 300º and 350º. Today I'm between 350º and 370º with brief excursions to 400º.
I need to find a better way (or bigger axe) to make kindling. That almond is hard stuff!

[Larry P]

I overshot my temps every day until the day I decided to hit 900ºF, then I couldn't get it that hot. It's a difficult game, just take it slow.

For kindling, I was using a hatchet and small sledge hammer, but just bought one of these:
http://www.kindlingcracker.com/

It arrived yesterday. I haven't tried it yet.

[SteveB48]

DAP Silicate Cement Black arrived yesterday.

I have 2 layers of insulation on the oven. I'll get the third one and the lathe installed on Saturday. It's amazing how much bigger it looks with 2 layers of insulation.
I'm up to 550º as of last night. I checked the oven this morning at it's at 320º. I don't have an insulated door yet. So far I'm just using the outside metal plate.

I started using the kindling method you described a couple days ago. Much better. Let me know how the Kindling Cracker works. I was looking at that as well.

Maybe Pizza this weekend.

[Larry P]

Kindling cracker works! It's the epitome of reliability. Zero moving parts. I'll put up a video this weekend if you like.

[SteveB48]

Nice! I'll check it out.