Glass Shatter?

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Ridgewood

New Member
Oct 21, 2018
28
Westchester, NY
I have a Jotul 550 Insert - and sometimes a large piece of wood will tumble and lean against the front glass. Should I have any concern that this bright red burning piece of wood is full on burning against the glass?

The wood doesn’t come crashing into the glass - so i’m not concerned about that - its the heat rating / will the glass shatter from the intense heat.
 
no stove glass isn’t subject to thermal shock like normal glass rapid heating or cooling won’t do anything ( impact and flexing are the weak points of robax and ceramic glass)
 
Not sure what the 550 firebox internal dimensions are but have you considered loading your splits straight in or what is commonly called a north -south arrangement?
 
I believe it's not glass as we're usually familiar with such as pyrex, but a clear ceramic. It can be heated to far greater than stove temps and not loose it's form or become brittle.
 
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Never had a problem with that. Just don't slam the door onto a split sticking out too far.
 
My Rockland does this more than I would like. Firebox designed for east-west burns only and the andirons are useless. Wood against the glass here and there is ok. Just don’t get anal and open the door thinking you can fix the issue in progress, as the wood is likely to fall out of stove.
 
image.jpg Same here CTwoodtick. I burn slabs and there constantly tipping forward. Actually been using the andirons to my advantage and been putting a part of my first piece on them tipping the stack backwards a little. Helps on and off. Dave T.
 
Well, this is good to know. My first year with a stove, and wood has fallen against the glass once or twice. It worried me, but opening the door worried me more.
Thanks for this thread.
 
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Happens to me occasionally as well. I can only burn E/W and when it does I gauge how long it would have to be like that, meaning is it kinda coaling or still a have to burn awhile. My hearth really heats up a lot more when that has happened as well. So, I put on the gloves, then barely open the door trying not to let it completely fall out, then squeeze the fire poker thru the little gap and hope to hold/catch as much as possible then grab it and maneuver it back in the box. Usually there's a little more mess, so scoop the coals and dust off. You will remind yourself when you load the box next time to be aware of how it's going burn and strategically place the logs in the jigsaw fashion a little better.
 
As mentioned, the thermal aspect is nothing to worry about. Sometimes a fresh piece of wood near the glass will leave a tar / soot stain that is hard to get off - unless you're planning a good hard 'glass cleaning' burn, anyway.

Many moons ago, I had a log roll forward and break out a 'glass' pane. The ceramic sort of breaks like you'd expect of normal window glass... maybe just a crack, or spiderweb, or similar. It doesn't break into a million little pieces like you'd expect of tempered glass. In my case, it made a spider web and one little (2" x 3") pie shaped piece fell out. That immediately let a jet of air in and turned the whole thing into a blast furnace. I put a 'patch' of several layers of aluminum foil over the hole until things settled down.

Now I try to be a bit more careful when loading... rounds typically on the bottom / back. Bows and splits stacked so they have a natural tendency to fall 'into' the stove and try not to stack small things in the middle which burn away and let a big chunk on top fall.

Every once in a while something will still shift, but so far, so good over the past ~20 years...knock on wood!
 
No worries . . . as mentioned the material is actually a ceramic or similar material and is extremely resilient in terms of temperature and even an occasional blow.

About the only time I hear of cracked "glass" is when someone rams their poker into it or attempts to slam a door shut with too long of a split or round.

Worse part of wood resting against the "glass" is the smudge it makes.
 
No worries . . . as mentioned the material is actually a ceramic or similar material and is extremely resilient in terms of temperature and even an occasional blow.

About the only time I hear of cracked "glass" is when someone rams their poker into it or attempts to slam a door shut with too long of a split or round.

Worse part of wood resting against the "glass" is the smudge it makes.
Totally accurate but the slightest impact from something hard is all it takes . My friend Ed was changing a light bulb on a six foot ladder , I asked for the truck keys and he dropped a nickel from his pocket it hit the second step and bounced of the bottom step it traveled about 6-8’ and just barely had enough velocity to make it to the door glass and literally just tapped the glass and it cracked right in 2 . If I hadn’t witnessed it I would have sworn he was exaggerating about the distance and the ultra slow speed ( it really looked like it happened in slow motion ) moral of the story ceramic glass is WAY more brittle than any actual type of glass
 

Durable unless hit at just the right frequency.
 

Durable unless hit at just the right frequency.

Impact, and also close to zero thermal coefficient is something a guy can get a handle of. Do you have a video, or can you cite another source for a frequency test. Not sure if I'm believing it yet.
 
I recall someone posting this video or something very similar a year or ago. But hit ceramic window the wrong way with a poker, or jam the door into a log and I wouldn't be surprised if they'd crack.
Hitting window with a 2 x 6 isn't something I'd do with my personal stove, but I guess if I were a sales rep I wouldn't have a problem.

I had a friend who was a Ceramic Engineering student. He brought back some super tough ceramic marble samples. You could slam them into a hard surface without damage to the marble. They were practically indestructible.