Trying to keep my Fisher alive

[DianeB]

Have had my Fisher Mama Bear since 1978 and have used it as our primary heat source in Western Massachusetts. Because of storms last Fall, we decided to repair our masonry chimney and then got involved in a total rebuild. We had to pull out the stove (had been connect to a stainless liner) and it was then we noticed the outet collar was separating from the collar as it went internal. Can we solder the collar back on to the rest of the collar? We are looking for a mobile welder to do this job and hoping Coaly or others may have some suggestions. Also found some hairline crack in the back about 1/4 inch if that on either side of the collar - these look to be hairline. Could we fix this as well?

About 10 years ago we had a chimney fire and therefore ended up with the stainless liner as the red liner in our chimney was cracked from the fire.

Lastly, the stove going on 33 years old and on examination, I noticed two fire bricks on each side cracked - I think each was the 4th one in from the front. One is a more than cracked - a small triangualr chunk missing.

I have no idea on how to take out and replace the bricks - do masons do this kind of work?

Love our Fisher and hate to retire it as it has been so good to us and odd to say, almost a member of the family. The new EPA stoves do not thrill us at all. Hoping you guys have some good advise for me. My grown kids are angry that we are even considering retiring the stove -they don't even live with us anymore and they are upset. My husband is not physically able to do this work himself any longer so have to find welders etc. to help us. I do have lead on a mobile welder but not sure if he is familiar with this kind of work and the fire bricks stump me -they look jammed in their pretty good and even if I smashed and hammered them out - I would have not clue as to how to reset them.
thanks in advance for advice (or sympathy) whichever it may be!

 

[Crane Stoves]

Im sure it could be welded and the firebrick can certainly be broken out and replaced (the hairline cracks your talking about kind of scare me though), 30 years of good use... this thing owes you nothing, id buy a new stove at this point you deserve it!

 

[webbie]

Metal

Yes, this stuff can be repaired - welded by a guy with a mobile unit. My guess is that you can get it done for $100-$150.

Firebricks

Those types of cracks and even the missing piece, if smaller than a couple square inches, probably do not mean anything. The bricks are simply to keep the main large coals of the fire away from direct contact with the steel.

Personally, I'd probably do nothing...that is, if you want to use the stove...or patch up the big piece with a bit of refractory cement you can get in the hardware store....

Or, it is is time, sell it (someone will restore it!) and get a cleaner burning modern stove.

 

[DianeB]

Thanks for the info about repair-ability. I had not known about refractory cement but will give it a try. I would imagine I will have to clean the current bricks pretty well first - should I vac then use some TSP on them and let them dry and then apply the cement? Or could I just smear some on the dirty bricks?

hairline cracks may have been there since the fire - same with the collar coming loose where it meets the stove and the internal collar. The EPA stoves don't seem to have the burn time we need unless we get one that heats 2,500 sq feet and we only need to heat 1,500. Those burn times are 6-8 hours and I am afraid they may not give us an overnight burn or hold coals until we come home from work. Having to re-light twice per day using kindling and small chunks of wood would be a pain and i think the stoves I have check out that heat 1,500 take small pieces of would - we would have to re-cut 20's into 10's and then split even those to fit the 1,500 sq ft. stoves.

If the Fisher fix-up does not work out, any suggestions on smallish stoves?

 

[Crane Stoves]

You can muck up that refractory cement on almost anything and it will stick LOL (its kinda like hydrolic cement), but certainly give it vac. and quick once over scrape to remove any hangers and a wipe with a damp sponge (you dont need to etch or chemically treat the brick no matter what the directions tell you) I would be more concerned with the stress fractures of the steel, but thats just me (maybe nothing would happen if used again for years or overheated), what would tend to happen if these fractures were overheated is you would eventually start seeing the crack and warping of the metal to a point where the stove is releasing gases into the home (just keep your eyes on them, they can be welded also but once the metal has been compromised in this way it will always be weak and that CANT be fixed, most people would say the stoves life is up when they see stress fractures around it).

im not sure about todays woodstoves as much as i know about pre epa stuff but ive heard good reviews about the shanedoa (idk how to spell it) or the blaze king.... I will differ to some other members to make some suggestions about a new unit that might fit the bill for you. GL

 

[DianeB]

I am afraid of the fractures as well. I just took 3 pictures. Facing the outlet to the left is the largest of the two, the right is smaller and the outlet itself showing gap at top, but outlet attached the rest of the way around. You can't see light though through the fractures though so may just be surface. Hoping the welder is skilled

 

[BrotherBart]

I guess I am the only one that stove scares. With half that damage my old stove went out back for evening fires while I sit in a lawn chair. And a new one went into my fireplace. I am fond of this house.

 

[Prof]

I guess I am the only one that stove scares. With half that damage my old stove went out back for evening fires while I sit in a lawn chair. And a new one went into my fireplace. I am fond of this house.

I tend to agree--once metal is fatigued, that's as far as I'm willing to go. I also get why you wouldn't want to scrap it. Fisher stoves are listed on ebay and CL with regularity--you could probably find one for under $500 that is in decent shape. Just a thought.

 

[coaly]

I picked up a Mama Bear about a year ago for myself on Craigslist for $100. Then another for someone else off Craigslist in NJ this past February for $250. Probably cost as much to fix it as finding another.

One has to wonder if a 5/16 baffle plate across the outlet would have eleviated the high temp area on the back around the collar?? It would have directed the heat to the thicker top surface.

The bricks only set in place, but ash packs around them making them tight to remove without breaking one to remove them. Once the broken one is destroyed, the others can be slid into it's place to loosen and remove.

If you can get the stove on a vehicle, I'm not far south of RT 84 in NEPA. It would need to be dropped off (I have lifting equipment) and picked up at a later date. A 1/4" steel plate can be made to fit over the original back, and welded away from the stress area. I'm guessing about $200 repaired, rebricked, with new baffle added, without seeing the stove.

 

[DianeB]

I picked up a Mama Bear about a year ago for myself on Craigslist for $100. Then another for someone else off Craigslist in NJ this past February for $250. Probably cost as much to fix it as finding another.

One has to wonder if a 5/16 baffle plate across the outlet would have eleviated the high temp area on the back around the collar?? It would have directed the heat to the thicker top surface.

The bricks only set in place, but ash packs around them making them tight to remove without breaking one to remove them. Once the broken one is destroyed, the others can be slid into it's place to loosen and remove.

If you can get the stove on a vehicle, I'm not far south of RT 84 in NEPA. It would need to be dropped off (I have lifting equipment) and picked up at a later date. A 1/4" steel plate can be made to fit over the original back, and welded away from the stress area. I'm guessing about $200 repaired, rebricked, with new baffle added, without seeing the stove.

We travel that route (84) to get from western mass to northern virginia to visit family. I would love to get our stove to you, but not sure about truck availabilty, I will have to look into this.

Would you lay the new steel plate on top of the entire rear exterior of the stove or would you cover sections that are damaged with pieces of steel plate? Is the baffle the shelf inside just under the outlet?. Thanks for all the info coaly, could tell from reading your fisher history you have a passion for these stoves.

 

[coaly]

The rear is welded around all four sides, then the angle iron is tacked top and bottom over the back plate. It's not worth removing and replacing the entire back sheet, so I'd cut a piece of 1/4" plate (the same material stove back is made of, lay it on top of the affected area and weld all th eway around it. Including welding it to the collar.

A Smoke Shelf Baffle Plate was added to the double door stoves after 1980. 5/16" thick, same as top material. It's a good idea to add to any model. Here's a description with pictures. It sets on the small horizontal plate under the outlet, and can be supported by a brick on each side. Factory baffles had angle iron welded inside the stove to make a shelf to sit on. It directs the heat to the stove top instead of the rear of the stove. It also helps roll the smoke back ito the flame, and a high flame goes up the plate and hits the top of the stove. Any smoke passing between the plate and stove top (called the smoke space) has a good chance of being burned passing through the flame.
https://www.hearth.com/talk/threads...d-fisher-more-heat-less-smoke-under-25.74710/

Was this stove set back in a fireplace recess to prevent good air circulation around the back?

 

[DianeB]

The rear is welded around all four sides, then the angle iron is tacked top and bottom over the back plate. It's not worth removing and replacing the entire back sheet, so I'd cut a piece of 1/4" plate (the same material stove back is made of, lay it on top of the affected area and weld all th eway around it. Including welding it to the collar.

A Smoke Shelf Baffle Plate was added to the double door stoves after 1980. 5/16" thick, same as top material. It's a good idea to add to any model. Here's a description with pictures. It sets on the small horizontal plate under the outlet, and can be supported by a brick on each side. Factory baffles had angle iron welded inside the stove to make a shelf to sit on. It directs the heat to the stove top instead of the rear of the stove. It also helps roll the smoke back ito the flame, and a high flame goes up the plate and hits the top of the stove. Any smoke passing between the plate and stove top (called the smoke space) has a good chance of being burned passing through the flame.
https://www.hearth.com/talk/threads...d-fisher-more-heat-less-smoke-under-25.74710/

Was this stove set back in a fireplace recess to prevent good air circulation around the back?

The stove was set in front of the fireplace box. The fisher was actually an inch too high to fit in the box, was perhaps 2 inches in front of it. If we had a fire in the outlet pipe, would this have caused cracking of the back around the collar? I checked your link and see what you mean about the shelf being added. Ours does seem to have a little shelf there already, will have to take a picture and post. We installed our in 1978 and is a momma bear - we bought it new - I think for $400 which was a fortune then.
.

 

[coaly]

No, the fire from burning debris in the pipe would rise overheating the chimney liner. Free circulation air around the stove is needed to radiate heat into the air keeping surface temperature weakening steel. Cooling down from a dull glow over and over will fatigue the metal, starting with cracks radiating from outlet hole. The combination of flame moving toward the back and out the outlet with less airspace at the back creates the highest surface temperatures right where it cracks. Doubling up the metal also acts as a heat sink lowering temperatures at the outlet.

Here's a picture of a half inch thick aluminum plate across the back of my kitchen cook stove and heat source in the house. A 24 gallon water tank sits on it, and this moves the heat into the tank with better heat conductivity than steel. It gets another piece around the outlet cut in a radius to fit the pipe. This extracts the normally wasted heat around the stack and transfers it into the water with increased area of tank contact. A second benefit is keeping the area where yours shows fatigue cooler.

 

[DianeB]

Does anyone know how much the Mama Bear weighs? I found the link to the manual, but the manual does not list the weight.

 

[coaly]

370 pounds with brick. A hand truck under the side moves them nicely. I put a couple short 2 X 4's across the foot of the hand truck to press on the bottom so it tilts easily. Going through doorways, if you have to go lengthwise, it's nice to have a rectangular furniture dolly with 4 wheels. To get them into a truck or trailer, I use a couple 2 X 6's as a ramp and lay them on their side and "walk" them up. Picked many up by myself, without lifting. It's all about keeping it on wheels! Steps are the issue if you have any to deal with.

 

[DianeB]

"The rear is welded around all four sides, then the angle iron is tacked top and bottom over the back plate. It's not worth removing and replacing the entire back sheet, so I'd cut a piece of 1/4" plate (the same material stove back is made of, lay it on top of the affected area and weld all th eway around it. Including welding it to the collar."

Coaly - your advice above...how far down the back should we go - the entire back or perhaps just a few inches around the collar - say 4-6 inches?

I got the stove on the deck with a dolly - a friend's husband does excavation work and weld repairs all his equiment - he is going to come check out the stove for me (truck show season so can't for a couple of weekends - LOL

 

[coaly]

A couple inches is fine, just so the weld is on solid metal away from the cracks. He'll probably know to "stop drill" the crack as well if he works on heavy equipment.