Grandpa bear baffle insulating question

[45cheese2]

I got my hands on some "kao wool" from work. I think that's the correct terminology. I think it's ceramic insulation. We run it in a furnace that runs steady at 2500-2600⁰f. I have been putting it in the Fire box of my square door grandpa bear. It's too warm to burn yet here, so I don't want to test it out yet.

I have installed a baffel earlier this summer per coalys instructions. And I just installed this insulation wool behind it. Has anyone ever done this and what kind of performance could I expect?
I have added extra fire bricks to hold the baffel where it matched the chimney as you can see in the pictures attached. The baffel plate had to be 3/8 as 5/16 wasn't available. Would the insulation behind it help keep it hotter? I looking forward to try this when the weather allows.
Should I expect increased box temps and even less smoke out of the chimney? Thanks for checking this out.

 

[Wisco Shepherd]

Id hold my breath when opening the door for loading and the like. Insulating wool like that spits out all sorts of carcinogens when exposed to flame directly. My forge uses kao wool but gets coated in a refractory cement for this reason.

 

[bholler]

Id hold my breath when opening the door for loading and the like. Insulating wool like that spits out all sorts of carcinogens when exposed to flame directly. My forge uses kao wool but gets coated in a refractory cement for this reason.

That is not true it really isn't effected by flame at all. It's used in side stoves unprotected all the time.

 

[Wisco Shepherd]

That is not true it really isn't effected by flame at all. It's used in side stoves unprotected all the time.

I have some that helps seal the bypass on my baffle but is not that exposed. I personally wouldn't use it that exposed in the firebox like he has especially if a piece of wood bumps into it and pulls it out. Then again I am used to using it in a 2000 degree forge and the blacksmithing community generally seals their wool to the best of their ability because of this. Maybe this product in this application is fine.

 

[Wisco Shepherd]

https://www.insulationindustries.com.au/wp-content/uploads/2022/05/MSDS_-_Kaowool_Blanket_and_Bulk_Products.pdf

Here is a safety sheet if you are interested.

 

[45cheese2]

OK I never thought of dredging up the sds for it. I'll see how bad I fu"ked up

 

[Wisco Shepherd]

OK I never thought of dredging up the sds for it. I'll see how bad I fu"ked up

The stuff behind the baffle is likely fine but the exposed stuff in the firebox is what I would personally avoid. If you got a mason wheel for your grinder you could cut firebricks to fit those angled areas and get some insulating effect that way.

 

[bholler]

The stuff behind the baffle is likely fine but the exposed stuff in the firebox is what I would personally avoid. If you got a mason wheel for your grinder you could cut firebricks to fit those angled areas and get some insulating effect that way.

I would absolutely do that just for durability. I see no potential danger there. If any silica is made there it's going to be sucked out the chimney

 

[Wisco Shepherd]

I see no potential danger there. If any silica is made there it's going to be sucked out the chimney

I do lots of cold starts so loading it up and messing with it while the stove is cold and not drafting would give me some concern. The risk may not be as bad as I initially stated but ill just leave the TDS for the OP to ponder and call it at that. I'm no princess on safety either I even split wood without eyepro.

 

[bholler]

I do lots of cold starts so loading it up and messing with it while the stove is cold and not drafting would give me some concern. The risk may not be as bad as I initially stated but ill just leave the TDS for the OP to ponder and call it at that. I'm no princess on safety either I even split wood without eyepro.

Oh I totally support you raising any concerns you have. But even in the tds the only concerns are about the possible production of silica and of course the air born fibers. Both of which are an issue with just wood ash in general already. So personally I don't really see any elevated safety risk because of this. But absolutely encourage everyone to look at the info and make their own decision.

 

[45cheese2]

OK. Thank you for all information. Would this have a positive impact on performance compared to just the steel plate? Is more heat going to stay in the stove and burn the smoke rather than go up the chimney?

Great safety meeting by the way. I'll look into that and talk to an engineer at work about it

 

[bholler]

OK. Thank you for all information. Would this have a positive impact on performance compared to just the steel plate? Is more heat going to stay in the stove and burn the smoke rather than go up the chimney?

Great safety meeting by the way. I'll look into that and talk to an engineer at work about it

It may improve efficiency slightly.