I am looking at installing an insert, and looking at the TN20 by PE and CW2900 by STI. The 20 is listed as 10 gauge steel construction, while the 2900 is 5/16”. That’s a big difference in my mind, and wondering what roll the thickness plays in stove construction nowadays. Between these two stoves, one is 1/2 the thickness of the other.
Stove steel thickness
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kennyp2339
Minister of Fire
I would stick with the cw2900 for the larger fire box and heavier material used.
Gearhead660
Minister of Fire
I think that’s the way I’m leaning. I really like the option of N/S loading of the TN20, but the CW2900 is a proven heater, has larger firebox, and not to mention $300 cheaper.
Does seem to be quite a difference. 5/16 is ~ .312" and 10 gauge is about .134" So I think the typical note is that a thicker stove will last longer.
Though I am burning a stove from the '80s or possibly early 90's. It has a ~5/16" thick top sheet in the firebox. I'd be hard pressed to say it has deteriorated much at all. If I'm generous, maybe .010 inch gone due to light oxidation on the steel surface ?
So even if I assume it was never burned before I got it (though the guy I bought it from said "it's our main heat, I'll let the fire die out and you can come back tomorrow to pick it up when it's cool"), It's lost 0.010" in 18+ seasons of primary house heating with me. If I throw it out once the metal is down to half thickness, then it's barely got 250 seasons of heating left!
The same rate on a 10 gauge stove, you'd burn away half the thickness in barely 120 years!
The other thing - I suspect in modern stoves, direct flames hitting steel (key contributor to steel burning away) probably doesn't happen. They have refractory lined fireboxes and baffles to take the heat and flame, then its the flue gas going through the rest of the stove.
But either way, hard to believe a decently cared for stove wouldn't last a lifetime, or more.
Though I am burning a stove from the '80s or possibly early 90's. It has a ~5/16" thick top sheet in the firebox. I'd be hard pressed to say it has deteriorated much at all. If I'm generous, maybe .010 inch gone due to light oxidation on the steel surface ?
So even if I assume it was never burned before I got it (though the guy I bought it from said "it's our main heat, I'll let the fire die out and you can come back tomorrow to pick it up when it's cool"), It's lost 0.010" in 18+ seasons of primary house heating with me. If I throw it out once the metal is down to half thickness, then it's barely got 250 seasons of heating left!
The same rate on a 10 gauge stove, you'd burn away half the thickness in barely 120 years!
The other thing - I suspect in modern stoves, direct flames hitting steel (key contributor to steel burning away) probably doesn't happen. They have refractory lined fireboxes and baffles to take the heat and flame, then its the flue gas going through the rest of the stove.
But either way, hard to believe a decently cared for stove wouldn't last a lifetime, or more.
Woody Stover
Minister of Fire
I guess you bought the BK before you knew it was 10 GA..
BKs are 10 Gauge! That makes me feel better about the TN20. I wasn’t looking at the BKs at all as I didn’t want a cat stove. Thanks for the heads up on that tidbit.
10 gauge stoves can hold up perfectly fine and thicker stoves can be destroyed in a season. It all depends on design build quality and how it is used.
Woody Stover
Minister of Fire
That's just the sides on the BKs, top is thicker. I don't know how a 10 GA top would hold up. I'd be leery of thin steel in a cat stove, since there's a lot of creo condensing in the box. I'd want more thickness. In a secondary stove, that's not really an issue. A 5/16" top is super-thick! Even the mighty Buck 91 had only 1/4" box, top and sides.
Yet bks hold up just fine. You press this issue all the time and it just isn't an issue that causes problems
Yeah the TN20 has a thicker top, think it’s 1/4”. I may just go that route as it does allow the N/S loading, and has slightly lower clearance distances.
Thanks all for the input
Thanks all for the input
Woody Stover
Minister of Fire
On the contrary, I've heard of some that rusted through.
I don't really dis on the BKs anymore..caveat emptor. But when a BK guy tees it up like Kenny did, it's hard for me to resist.
I wonder how many stoves other than the TN20 have a 10 GA top? I haven't seen near as many stoves as you have, but I've only come across specs of 3/16" in the literature I've seen.
The problem is there just isn’t a lot of info on the TN20. It says it’s construction is 10 ga steel, but also says “heavy plate-steel top” so I’m assuming it’s thicker than 10ga.
I have seen rusted out stoves of all thicknesses. If your concerns were valid we would hear about it allot more. Cracking due to abuse or not allowing for differences in expansion rates are far more common failures. And thickness plays very little into that issueOn the contrary, I've heard of some that rusted through.
I don't really dis on the BKs anymore..caveat emptor. But when a BK guy tees it up like Kenny did, it's hard for me to resist.
I wonder how many stoves other than the TN20 have a 10 GA top? I haven't seen near as many stoves as you have, but I've only come across specs of 3/16" in the literature I've seen.
kennyp2339
Minister of Fire
Now my stove season is complete.. got my 2 cents from Woody lol, missed you pal!I guess you bought the BK before you knew it was 10 GA..
Woody Stover
Minister of Fire
I'm seeing 10 GA, sides and top, but maybe that's not correct. That was the insert. I assume the insert and free-stander would be the same box but maybe not? I guess I'd be less concerned about thinner steel in the top in an insert, since the blower would keep top temps lower over all.
When I heard a loud pop, and thought I had possibly broken a weld on the Buck 91, I examined the stove and found some creosote erosion when I removed some firebricks. That stove was under ten years old. The "pop" was apparently a side flexing.
I don't know how you, much less an owner, would even be aware of such a problem unless the bricks were removed? Some guys in that thread said they were going to look behind their bricks, but I didn't see any subsequent posts, except for one guy that said he found some deep pitting. Maybe you would never know, even if it rusted through, if there wasn't a major performance issue to tip you off. I don't know when BK sales took off in earnest but with more of them in the field nationwide now, any issues should come to the fore as time passes.
When I saw the creo erosion in the Buck I said, 'At least it's gotta eat through a quarter inch..that will take a while.' If I'm getting less steel, I'd like to see a correspondingly lower price, but that's just me.
I'm curious to know more about the "differences in expansion rates" that you mentioned? Is that from running the stove too hard when bringing it up to temp, or what?
Back to the OP's question, I don't think creo erosion would be an issue with a non-cat since they don't smolder-burn like a cat might.
It's not always an option but I hope he can see both stoves in person to answer the steel question, and compare other features firsthand.
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I’ve seen a few pictures of one that wasn’t all that old and the thing had a hole burned through the bottom corner of the fire box. Sorry, but that has always deterred me and bothered me.On the contrary, I've heard of some that rusted through.
I don't really dis on the BKs anymore..caveat emptor. But when a BK guy tees it up like Kenny did, it's hard for me to resist.
I wonder how many stoves other than the TN20 have a 10 GA top? I haven't seen near as many stoves as you have, but I've only come across specs of 3/16" in the literature I've seen.
Many of the manuals for many of the new stoves I have studied for the last several years absolutely call for the hottest quickest fire you can build to prevent smoking out the chimney to satisfy the EPA...that is where the cracking issue is coming into play. Too hot too quick in cold stoves. It’s an easy way for manufacturers to pass the buck onto consumers and call it “abuse”. That said, I have no doubt some of your statement is true about true stove abuse, but it’s also an easy out for the manufacturers.
Just today I watched a YouTube video of a couple in a tiny home lighting a Jotul 602. The couple had heavy winter coats on inside the home, and a large pot of water sitting on top of the stove had 1/4” ice in the pot.
The first thing they did, instead of some wood shavings and 3-4 small pieces of kindling, was they filled the fire box full and lit it off and within 3 minutes burning super hot. That cast iron stove won’t ever last as long as it should for that couple. What a shame. That sort of stuff is even hard on a steel stove.
People are free to do what they want, but just because some pencil pusher says to do something doesn’t make it right. Most stoves, regardless of steel thickness, cast iron, soapstone, will last longer and in the long run take more heat if you heat them slowly at the onset of burning. Same with clay lined chimney’s. It’s no wonder they freaking crack...thermal expansion of a natural made product. Duh. It will bust wide open every time. Heat that clay slowly and properly and it’ll take more heat than most would imagine. I’m not suggesting it is superior or inferior...I am simply saying that these goofy videos shown by these chimney “police” organizations don’t tell the entire story. If the clay liner is clean to start with and heated slowly then a stove fire will not crack it no matter how hot. The key is clean and warmed up slowly. They show one section of new clay liner, stuffed full of news paper, light the fire, and bam...it bursts wide open. Meanwhile, everyone standing in the video has a winter coat on. It’s no wonder it bursts. Heat it slowly and that won’t happen unless the liner is full of glaze.
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So everyone should bring their stove and uninsulated clay liner chimney up to temp very slowly to avoid thermal stress? What do you think that will do to the walls of that chimney? Those pencil pushers are trying to help.you minimize creosote buildup which getting up to temp as fast as possible does. If the stove is designed properly so it allows for expansion differential it will be fine. And btw getting a stove up.to.temp as quickly as possible is noting new people have been doing that long before the epa was even a thought
So where are all of these rusted out stoves? Why don't we hear about them constantly?
Highbeam
Minister of Fire
Meh, steel thickness is overrated as an indicator of quality. Properly engineered stoves don’t need the crutch of overly thick steel. A well designed thin steel stove would heat up fast and start heating the room that much sooner. If your combustion technology needs thermal mass to smooth out the peaks and extend the “heat life” then the cast iron double wall seems like a nice way to get that mass. Looks great too without the drawbacks of a true cast iron stove.
We see lots of cracks on the forums but not much rust through. I saw the rusty BK and I’ve seen a cracked Bk but I’m sure it’s rare.
We see lots of cracks on the forums but not much rust through. I saw the rusty BK and I’ve seen a cracked Bk but I’m sure it’s rare.
So now, let’s take a cold chimney and light the hottest fire we can get in the stove. Absolutely brilliant. Sort of like going to the local college town and watching all those
mart young kids walking out in front of cars. Yeah...they’re smart alright.
My point was the manuals mention quick and hot fires to prevent smoke but they don’t go on and tell the entire story, that a really cold piece of cast iron can crack if you expose it to high heat too fast. I see these cracked stovesnalo the time, cast iron and soapstone. Only two ways they can crack, thermal stress fatigue fro cold to hot or over-firing. Otherwise if heated carefully they can take whatever you throw at them. The same reason antique cast iron stove collectors make casting repairs to cracks by cooling them slowly over a 24 hour period. They often slow heat them even before welding. Those repair methods alone tell you how to care for the castings, by slowly heating and slowly cooling. Natural stone or clay needs the same thing. Steel, somewhat of a different animal. I don’t for a second think I need to tell you these things. You know them.
At least one manufacturer has went to great trouble to deal with expansion and contraction of their stoves to eliminate metal fatigue between the outer shell and inner firebox and to prevent the noises associated with expansion and contraction. Apparently they thought it important enough an issue to deal with it.
Never said those pencil pushers didn’t minimize creosote...I said they don’t tell the entire story, and they don’t. We’ll agree to disagree. I know we’re not talking specifically about cast iron or natural materials, but a cast iron stove, like a good cast iron skillet, both should last more than a single persons lifetime with some common sense approach to proper care and proper heating and cooling...and it’s really that simple.
mart young kids walking out in front of cars. Yeah...they’re smart alright.
Don’t take my words out of context, Ben. Let’s keep it real. I’m not talking about a stove that has went out and warm air goes up the chimney when the door is opened. I’m talking about a cold house, stove, and chimney, not luke warm. And don’t tell me taking the time to warm up a stove and “any “ chimney slowly, metal or otherwise, is going to cause a creosote issue one time or ten times. Even when I burned wood, my stove was started and rarely went out for the year. Get it up to temp, then burn hotter than normal cruise for a 1/2 to an hour each day and there won’t be any issues if the system is built right, clay or not. That’s with older stoves. Should be less issues with these new “cleaner burning “ stoves just by design. I don’t see an issue either way. Maybe you do because most people you deal with are not “regular” forum type people.
My point was the manuals mention quick and hot fires to prevent smoke but they don’t go on and tell the entire story, that a really cold piece of cast iron can crack if you expose it to high heat too fast. I see these cracked stovesnalo the time, cast iron and soapstone. Only two ways they can crack, thermal stress fatigue fro cold to hot or over-firing. Otherwise if heated carefully they can take whatever you throw at them. The same reason antique cast iron stove collectors make casting repairs to cracks by cooling them slowly over a 24 hour period. They often slow heat them even before welding. Those repair methods alone tell you how to care for the castings, by slowly heating and slowly cooling. Natural stone or clay needs the same thing. Steel, somewhat of a different animal. I don’t for a second think I need to tell you these things. You know them.
At least one manufacturer has went to great trouble to deal with expansion and contraction of their stoves to eliminate metal fatigue between the outer shell and inner firebox and to prevent the noises associated with expansion and contraction. Apparently they thought it important enough an issue to deal with it.
Never said those pencil pushers didn’t minimize creosote...I said they don’t tell the entire story, and they don’t. We’ll agree to disagree. I know we’re not talking specifically about cast iron or natural materials, but a cast iron stove, like a good cast iron skillet, both should last more than a single persons lifetime with some common sense approach to proper care and proper heating and cooling...and it’s really that simple.
I would say steel thickness contributes as much to a hotter firebox as does firebricks. Maybe not equally, but so much as at least some contribution is made, not to mention the additional radiance factorGive me additional mass any day of the week over a thin stove.
Stoves like those old duel fuel box stoves from Sears, Warm Morning, Ashley, King, Wonderlux, etc., all of sheet metal. Heating monsters until you over-fire one and then they’re toast.
Stoves like those old duel fuel box stoves from Sears, Warm Morning, Ashley, King, Wonderlux, etc., all of sheet metal. Heating monsters until you over-fire one and then they’re toast.
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