Rasoul jaan,

We've decide to use a 304 SS fireback to line the aging and now dirty brick in the back of our wood fireplace. I can get 304SS fabricated no problem, but ideally, I'd like to "glue" it to the firebrick at the back and sides of the fireplace. I know most construction adhesives would fall apart at high-temperatures and specialty adhesives (aluminum oxide or high temp. epoxies) are quite expensive (over $100 for a pint).

Theoretically, I could let the plates "float" in there, but I would like them to be secured to the back, to reduce warpage and wobbling if there's an inexpensive solution. Since you're in the auto industry, do you know of any easy application and readily available adhesives that are good up to around 1500 °F (slightly hotter than car exhaust)?

I did a few quick searches and other than the specialty stuff, I couldn't find anything. I figured I should ask you before I spend hours figuring it out.

Many thanks in advance.

Rasoul jaan,

We've decide to use a 304 SS fireback to line the aging and now dirty brick in the back of our wood fireplace. I can get 304SS fabricated no problem, but ideally, I'd like to "glue" it to the firebrick at the back and sides of the fireplace. I know most construction adhesives would fall apart at high-temperatures and specialty adhesives (aluminum oxide or high temp. epoxies) are quite expensive (over $100 for a pint).

Theoretically, I could let the plates "float" in there, but I would like them to be secured to the back, to reduce warpage and wobbling if there's an inexpensive solution. Since you're in the auto industry, do you know of any easy application and readily available adhesives that are good up to around 1500 °F (slightly hotter than car exhaust)?

I did a few quick searches and other than the specialty stuff, I couldn't find anything. I figured I should ask you before I spend hours figuring it out.

Many thanks in advance.

Mr, G.

Red RTV (example, Permatex 26B available through Auto parts and hardware stores) is supposed to be high temp. resistance up to 1600 deg. F., they are cheap, around 3.50 USD per tube, you might want to buy 1 just for testing.

At other hand why don't you use floating installation method. basically drill a hole in the mansonary, drive in metal anchor, pass a long screw through a metal spacer (size will depend on the desired gap between the metal shield and the wall, also you can make spacers by cutting them from metal tubing) then screw in the whole thing in the anchor. Just a thought.

Thanks so much for the info Rasoul jaan. The floating method was actually my first thought (since it is a better design to reduce stress/warpage from thermal expansion), but I'm a little worried about putting holes in the firebrick - not sure what the code says about this and I didn't want to take any chances.

I really like this RTV suggestion, especially since it's gasket material and designed for heat cycling. But I looked up a couple of different products (Permatex & Loctite) and they all say intermittent temperatures up to 700°F. Am I looking under the wrong heading or is the intermittent temperature lower than continuous operation - I know that's anti-intuitive, but I noticed that with the other high-temp bonds as well. If that's the case, is it because of fatigue from cyclical loading that the intermitten temp. is lower?

http://www.thefind.com/cars/info-high-temperature-gaskets

Thanks so much for the info Rasoul jaan. The floating method was actually my first thought (since it is a better design to reduce stress/warpage from thermal expansion), but I'm a little worried about putting holes in the firebrick - not sure what the code says about this and I didn't want to take any chances.

I really like this RTV suggestion, especially since it's gasket material and designed for heat cycling. But I looked up a couple of different products (Permatex & Loctite) and they all say intermittent temperatures up to 700°F. Am I looking under the wrong heading or is the intermittent temperature lower than continuous operation - I know that's anti-intuitive, but I noticed that with the other high-temp bonds as well. If that's the case, is it because of fatigue from cyclical loading that the intermitten temp. is lower?

http://www.thefind.com/cars/info-high-temperature-gaskets

Mr, G.
Being concerned about codes is valid and vital IMO, but you will not drill through the width or the length of the whole brick, 1 or 1-1/2 inches top.

About Permatex 26B, We don't but I've seen many people using it as gasket material on engine exhaust headers which is the hottest spot in all internal combustion motors.

Also you might want to consult with DIY network, as I believe they have an active Q & A forum.

This site is also very resourceful with active Q & A.

http://www.naturalhandyman.com/index.html

Mr, G.
Being concerned about codes is valid and vital IMO, but you will not drill through the width or the length of the whole brick, 1 or 1-1/2 inches top.

About Permatex 26B, We don't but I've seen many people using it as gasket material on engine exhaust headers which is the hottest spot in all internal combustion motors.

Also you might want to consult with DIY network, as I believe they have an active Q & A forum.

This site is also very resourceful with active Q & A.

http://www.naturalhandyman.com/index.html

Many thanks Rasoul jaan. The Permatex is only a $5 investment, so I'll give it a try and let you know. If it fails, we'll move onto plan B, which is either a floating instllation or these super high-temp and more expensive bonds. I don't believe these 1600°F estimates at the firebrick anyway, because I've stuck my hand in there to play with logs many times (compliments of being a fire sign ;)) and never got any burns or even blisters. In comparisson, I stuck my finger on the discharge end of an exhaust stack after one of my mufflers in a bio-gas application and got a blister upon contact. The Engine exhaust temperature is only 950° and by the time it goes through the muffler (mounted outside) and an 8' non-insulated stack with outside temperature around 40°F, I estimate the temperature at the point I made contact was no more than 700-750°F. So, I think we should be okay with this RTV stuff. I'll keep you posted and many thanks again from both of us :)

Many thanks Rasoul jaan. The Permatex is only a $5 investment, so I'll give it a try and let you know. If it fails, we'll move onto plan B, which is either a floating instllation or these super high-temp and more expensive bonds. I don't believe these 1600°F estimates at the firebrick anyway, because I've stuck my hand in there to play with logs many times (compliments of being a fire sign ;)) and never got any burns or even blisters. In comparisson, I stuck my finger on the discharge end of an exhaust stack after one of my mufflers in a bio-gas application and got a blister upon contact. The Engine exhaust temperature is only 950° and by the time it goes through the muffler (mounted outside) and an 8' non-insulated stack with outside temperature around 40°F, I estimate the temperature at the point I made contact was no more than 700-750°F. So, I think we should be okay with this RTV stuff. I'll keep you posted and many thanks again from both of us :)

Geeeeeeeeeez Krist, Mr, G.
You probably need to take some form of finger management course, you have been sticking them in pretty hot spots.:D

Geeeeeeeeeez Krist, Mr, G.
You probably need to take some form of finger management course, you have been sticking them in pretty hot spots.:D

ROFL. You know it Rasoul jaan :Notooth2: