Yet another question about hairline cracks

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Griz

Member
Hearth Supporter
Dear friends,

I have a Lange 6302 wood burning stove that I just bought used from someone.
It is cast iron with enamel coating. I think it is beautiful.

It looks similar to this one that someone already posted in the picture gallery:
Lange 6302

I have a few questions.

1) The stove is made from separate metal panels that are fitted together and there are very slight gaps between the panels that get wider or tighter as the stove heats up and expands or cools down. Sometimes I can see the faint glow of the fire through the gaps.
There isn't any apparent leaking of smoke into our living space.

a) Are these gaps normal or should I be concerned?
b) Will the gaps affect the performance of the stove?
c) Should I use some kind of furnace cement to try and seal the joints?

2) There is a small hairline crack on the left side panel about 2 inches long.
See the photo below:

[Hearth.com] Yet another question about hairline cracks




a) Should I be concerned about this?
b) Should I try and stop any further cracking by using any cement on the inside? If so, would you recommend using High Temp Silicone Cement or some kind of furnace cement?
c) Will this affect the resale value of the stove?

3) Do you think $550 is a reasonable amount to pay for this stove?

4) Does anyone know what the date of this stove might be?

Thanks much!
 
Stove is probably about 1977-80

The front crack is in the seam where the stove is put together. You can apply furnace cement from the inside - after cleaning the area and making it a bit damp. Squeeze the furnace cement using your fingers from the inside.

As far as the side crack, that is a cracked casting.....not a good thing, but it is rare that a crack like this expands too much, and almost impossible for the stove to fall apart. Some people used to suggest that a repair might be to drill a small hole at either end of the crack - which might stop it from spreading. Personally, I would not do that unless the crack was actually spreading. You can spread some furnace cement from the inside over it...might hold for a few weeks or month.

As far as the price, that is a buyer/seller thing. It might be an OK price, except for the side crack. That does take some value off the stove.
 
A good welding shop that repairs diesel engine parts could weld a bead inside of the stove to seal the crack, but it might dammage the coating on the outside. Unless it travels, the worst it will do is give you a little extra air.
 
The stove should be completely broken down taken apart and all seams re done smearing refractory cement will crack out in no time It needs a total rebuild as for the crack again I would no pay a lot for that stove personally I would pass
 
Delete rant.
 
im afraid i gotta side with BB , the unit has a stress crack in the casting , and the panels are apparantly flexing apart while running from the heat of the fire,( assuming cause you said you could actually see the fire at times through the seam) this condition may not be fixable with refractory cement , when this condition occurs the stove is extremely succeptable to runaway or uncontrollable fires which are not a good thing. shame cause it is a pretty stove, but im not sure if it could be rendered safe without some major work , and even then it may not be completely trustworthy
 
Thank you all for your replies.

The panels do expand and contract, but after closer examination, I think not too much.

I think what is happening is that the original cement is starting to deteriorate here and there, leaving gaps between the joints, through which I can see the glow of the fire inside.

At this time, the natural draft is sufficient to pull the flames up the flu, but my concern is about possible continued deterioration and/or spreading of the crack. Some stove technicians suggested the problem is likely to just continue due to the expanding and contracting of the metal. Increases in the gaps could also result in hotter fires and possibly a fire hazard from the fire coming out of the stove. The same technician suggested I try furnace cement on the inside of the crack, but thought any smearing of furnace cement along the joints would be pointless b/c he thought it would just fall out shortly. Technicians recommended a rebuild to get the proper sealing, but unfortunately, that isn't possible b/c parts that are supposedly necessary for a rebuild are no longer available. This is all more than I want to get into at this point anyway.

Enuf said.
I welcome any further comments or discussion.

warmly,

Griz
 
I would put that stove in the corner of my L/R with a flower pot on top of it. ;-P
 
Bear in mind that the other plates in the stove have gone through the same number of burns as the plate that cracked: in our experience, there are more cracked plates in this stove's future.

If you do decide to put this critter into service, I'd side with Elk in recommending you completely disassemble it, grind the edges clean, and reassemble with fresh furnace cement. Then, keep your eyes peeled: any expansion of the present crack or appearance of a new one should be followed up with a trip to the metal recycler.
 
What are the parts required for the rebuild? Does the stove have a liner?
 
In short, the gaps are very normal and part of the stove design. They can be refilled.

The crack is the part that is not designed to "be". At the same time, there are a vast number of cast stoves being used that have hairline cracks in them. It cannot really be repaired in any "real" way other than replacement of the plate. On the other hand, the stove is not going to fall into pieces, etc.
 
To me I thought the educational part of this forum was directed towards safety. Cracks in the outer casing of a fire box is a sign of metal fatigue. I could never pass a stove exhibiting fatigue.
I would call into question that the fatigue is such, that it is unsafe and that it may be the beginning to further deterioration. No one here can claim it is just an isolated issue Also mentioned is heat flexing the joints. Again a real indication of metal fatigue. No amount of refractory cement will solve metal flexing

This statement is completely reckless and not representative of safety. Never should have been typed. I don't know why it was made. Griz it is my personal opinion you should disregard this statement it is totally wrong

At the same time, there are a vast number of cast stoves being used that have hairline cracks in them. It cannot really be repaired in any “real” way other than replacement of the plate. On the other hand, the stove is not going to fall into pieces, etc.

Every one of these cracked stoves should be taken out of service . Structural cracks a are fatigue fire box cracks metal fatigue where your safety should not be selfed off so calvalierly.
 
To answer one member's question about whether the stove has a liner or not: I am not sure b/c I don't know what a liner is. I can say that there are individual metal plates inside the stove, held against each wall with cotter pins. As for the rebuild, I do not know exactly what parts are required. I called a local company that has been around for a while and seems to really know wood stoves (Chimney Sweep, in Vermont), and they said that the parts weren't available for them to do a rebuild.

It does not appear as if the plates are flexing much, but I can see the glow of the fire through the side gap when it is hot, and I do notice additional areas where the cement has deteriorated and fallen out. When the stove is functioning, the gap is large enough that the stove makes a whistling sound as the air is sucked into the gap.

So, it seems as some of the forum members suggest that the crack may not be a problem in terms of functioning, and some suggest that the gaps and crack are just the beginning -- an indication that further deterioration is in store -- and pose a serious hazard -- and that the stove should not be used. Correct?

Griz
 
Griz said:
To answer one member's question about whether the stove has a liner or not: I am not sure b/c I don't know what a liner is. I can say that there are individual metal plates inside the stove, held against each wall with cotter pins. As for the rebuild, I do not know exactly what parts are required. I called a local company that has been around for a while and seems to really know wood stoves (Chimney Sweep, in Vermont), and they said that the parts weren't available for them to do a rebuild.

It does not appear as if the plates are flexing much, but I can see the glow of the fire through the side gap when it is hot, and I do notice additional areas where the cement has deteriorated and fallen out. When the stove is functioning, the gap is large enough that the stove makes a whistling sound as the air is sucked into the gap.

So, it seems as some of the forum members suggest that the crack may not be a problem in terms of functioning, and some suggest that the gaps and crack are just the beginning -- an indication that further deterioration is in store -- and pose a serious hazard -- and that the stove should not be used. Correct?

Griz

Correct. That stove is beyond its useful life. Just like my cracked stove that I junked last year.
 
I think to encourage someone to fire up a cracked stove is not good advice. Get a new stove, it might save your home and maybe your life.
 
I have the same stove. I also have a crack. Its on the top plate. I feal if its weilded properly it will not spread. I have an old wood stove I use in the back yard outside. It was weilded by someone once. The crack has NEVER spread at all. I really crank this thing up with wood and leaves ect.. The outside glows red ect..

its retared to scrap this stove simply beacuase of a small crack. I Would not pay 550$ for it though.
 
loust said:
I have the same stove. I also have a crack. Its on the top plate. I feal if its weilded properly it will not spread. I have an old wood stove I use in the back yard outside. It was weilded by someone once. The crack has NEVER spread at all. I really crank this thing up with wood and leaves ect.. The outside glows red ect..

its retared to scrap this stove simply beacuase of a small crack. I Would not pay 550$ for it though.

Welding cast iron is highly specialized. To do it properly requires someone with a large enough oven to bring the entire piece up to temperature and then a process to let the piece cool at the proper rate. It's an art form that seems to be dieing out (in my area at least) although there have been some new advancements in recent years.

I have a diesel head with a hole at this very moment. I found people who could do the job but the outcome is still going to be "iffy" although they will not tell you that. I ended up buying a used head to rebuild because the cost would be about the same and it's more likely to produce a good result in the end. I agree with the other poster - put flowers on it.

Kirk
 
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