Smoke baffle plate for a Fisher grandpa bear stove.

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TCater

New Member
Oct 8, 2022
4
Mason Michigan
Last year I purchased a Fisher grandpa bear stove. Im finally getting it installed next week. I was reading older post about installing a baffle. However my stove unlike other grandpas I have seen on here has three fire bricks tall on the sides of the stove, all sitting in the horizontal position. There are two small pieces of angle iron that are welded to hold the this run of brick (only brick is held there for the third tier of brick) would place my baffle on top of those pieces of angle iron? If so I came up with a measurement for the baffle being 29.5 inch wide and 8 inch tall. Thanks for your input all is appreciated! I will include photos of my situation with were I think the baffle would go, thanks again!

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coaly

Fisher Moderator
Staff member
Dec 22, 2007
4,727
NE PA
Normal width for a Grandpa baffle is 27 inches across.

That is a strange layout for bricks. There were some made wider, not sure of the reasoning behind it. Bricks fit without cutting when made to the drawing size. All fabricators had their own way of doing things that worked best for them. Could have been the size of steel sheets ordered causing waste.

Bricks normally fit 6 across the back, upright. So 6 bricks at 4 1/2 wide each totals 27 across the inside. Then sides were put in. To build a stove a little larger, it is made to install side bricks first, so the 1 1/4 thickness on each end added to 27 gives you the 29 1/2 inside measurement. I’m assuming your top would be 31 1/2 wide overall?

The cut sheet size for the back on Grandpa drawing is 24 x 27. That makes the top width 29 1/2 with overhang. I’m just giving you the specs from drawings. The cheat sheets the welders used (instead of dragging prints out of the office) is actually 27 1/4. This allows easier brick placement, ash fills in anyway, which is a good example of why fabricators deviated from the exact plans to make later stages of assembly easier.

All you can do is make a cardboard template and fit into stove. It’s nice when it can sit on brick retainers, not always practical with upper courses of bricks. May have to remove that top brick. It was not added to protect side sheets, no issues of warping there. Strictly to raise firebox temperatures with more brick. You will be doing that with the baffle.

I assume this is a unlisted model with angle iron corners since the UL Listed version had angle iron brackets on sides for a baffle support. For what it’s worth, the factory baffle was 27 X 3 1/2 inches in a Series III with baffle. That smaller plate size was due to not knowing what size chimney was being connected, allowing more heat than necessary up chimney in the case of larger chimney diameters used with existing fireplaces.

After setting template in place, measure opening that smoke will travel through. That square inch opening should be the same size as chimney flue square inch area. 8 inch round being 50 1/4 inches. So 29 1/2 across would require 1 3/4 minimum opening all the way across. This would be for a strong draft, so making the plate adjustable with shims you should be able to drop it for a 29 1/2 X 2 opening if you have elbows, and horizontal run to chimney that deceases draft. The minimum opening works well on a straight up insulated chimney. The key is to never go smaller than the chimney cross sectional area.
 
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TCater

New Member
Oct 8, 2022
4
Mason Michigan
Normal width for a Grandpa baffle is 27 inches across.

That is a strange layout for bricks. There were some made wider, not sure of the reasoning behind it. Bricks fit without cutting when made to the drawing size. All fabricators had their own way of doing things that worked best for them. Could have been the size of steel sheets ordered causing waste.

Bricks normally fit 6 across the back, upright. So 6 bricks at 4 1/2 wide each totals 27 across the inside. Then sides were put in. To build a stove a little larger, it is made to install side bricks first, so the 1 1/4 thickness on each end added to 27 gives you the 29 1/2 inside measurement. I’m assuming your top would be 31 1/2 wide overall?

The cut sheet size for the back on Grandpa drawing is 24 x 27. That makes the top width 29 1/2 with overhang. I’m just giving you the specs from drawings. The cheat sheets the welders used (instead of dragging prints out of the office) is actually 27 1/4. This allows easier brick placement, ash fills in anyway, which is a good example of why fabricators deviated from the exact plans to make later stages of assembly easier.

All you can do is make a cardboard template and fit into stove. It’s nice when it can sit on brick retainers, not always practical with upper courses of bricks. May have to remove that top brick. It was not added to protect side sheets, no issues of warping there. Strictly to raise firebox temperatures with more brick. You will be doing that with the baffle.

I assume this is a unlisted model with angle iron corners since the UL Listed version had angle iron brackets on sides for a baffle support. For what it’s worth, the factory baffle was 27 X 3 1/2 inches in a Series III with baffle. That smaller plate size was due to not knowing what size chimney was being connected, allowing more heat than necessary up chimney in the case of larger chimney diameters used with existing fireplaces.

After setting template in place, measure opening that smoke will travel through. That square inch opening should be the same size as chimney flue square inch area. 8 inch round being 50 1/4 inches. So 29 1/2 across would require 1 3/4 minimum opening all the way across. This would be for a strong draft, so making the plate adjustable with shims you should be able to drop it for a 29 1/2 X 2 opening if you have elbows, and horizontal run to chimney that deceases draft. The minimum opening works well on a straight up insulated chimney. The key is to never go smaller than the chimney cross sectional area.
I have taken some more photos of the stove along with measurements. I'm missing the second row of bricks in the rear (waiting for it to get installed before I ad them). I also noticed that they sit horizontal. Have you ever seen a grandpa with bricks like this, or one that had this wide of overall dimensions( pic of top plate and front measurements)? I cut a template out and measured the rectangle opening of 29.5 inch by 2 inch tall which gives me 59 sq. Inches of opening. So I should be good to go with my baffle. Thanks Coaly for you help and input.

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coaly

Fisher Moderator
Staff member
Dec 22, 2007
4,727
NE PA
Yes, that’s the wide body stove. Notice the curved door hinge plates to make the doors work on a wider stove.

Bricks I’ve seen are always upright. If there was drawings for your type, I don’t have them. It was common for the Virginia and West Virginia fabricators, the Dunn brothers to use curved plates on wider than normal stoves. Didn’t know anyone else made them like that.

Yes, that opening area for smoke path is fine for an 8 inch chimney.
 

coaly

Fisher Moderator
Staff member
Dec 22, 2007
4,727
NE PA
I also was wondering what is the best way to remove the door pins? Best tools and tricks? Thanks
They should remove easily when greased regularly. Tap them out or just lift the door straight up. Once loose and serviced correctly they should remove by hand. That's in a perfect world where someone has maintained the stove....... If they don't remove easily, you probably would not be asking the question.

Open and close door to see if the hinge pin is rotating with the door. If so, it is stuck in door hinge ear and rotating in the hinge plate. Clean any portion that sticks through the bottom of hinge plate. Sandpaper, Scotch Bright, wire wheel, anything to remove rust down to a clean pin. Apply penetrating fluid of your choice to both ends of pin. PB Blaster, Kroil, Liquid Wrench, WD-40 is better than nothing, or even oil mixed with kero or diesel fuel. After soaking overnight, try tapping them out. If they don't start to move, rotating with pliers or vice grips usually breaks them loose. If the pin is long enough to grip on the bottom, grip by head and bottom of pin to rotate back and forth without damaging pin head. Rotating breaks them loose better than driving out with a punch or chisel under the head.

When removing pins from door, there is a possibility of damaging pin heads. Vice grips or pliers should be enough to break loose by rotating. When they start rotating, lubricate and work pin out rotating and pulling upward. All is not lost if the vice grips or pliers mar the heads putting grip marks in the head. They were 3/8 solid rivets. If they come out undamaged, clean rust off with wire brush or Scotch Bright, or lightly sanding.

To make new pins, use a 3/8 bolt with no threads under the head with shank long enough to cut threads off. Grind bolt head points off with a bench grinder. Chuck the bolt in hand drill. Running hand drill in reverse, run the head against the running bench grinder to form head. A little practice makes original looking rivet heads easily. Cut to length removing threads. Chamfer cut end slightly.

Apply high temperature grease or silver anti-seize to pins when installing. Grease annually. Hinge pins should remove with your fingers easily.

Also lubricate threads behind air intake damper. Open door, open damper, reach through intake opening in door to apply silver anti-seize or high temp grease to threads. This will prevent wear on the damper bolts and door hinges.
 

dirtyjerzy

New Member
Nov 4, 2020
13
N.J.
My stove had a broken door hinge pin when I got. Ordered new pins off of Amazon. Remove the old pins with a hammer and punch. I put a bit of copper high temp anti size, once in a while the hinges get tight I put a few drops of penetrating oil on the.
 

TCater

New Member
Oct 8, 2022
4
Mason Michigan
I was looking around on my stove for any kind manufacturing identification. I found an H stamped in the middle of the angle iron on the ash fender. I also looked underneath the stove and found part of what looks to be the original sticker from the manufacturer. Looks like it says manufactured by Hesston corporation for Fisher stoves. Took pictures of both. Was hoping you had some info on where there shop was or were it was made thanks! Also thanks for the advice on the door pins. I do not think I'll replace them yet. I lubricated every moving part on the stove. No more squeaky noises, nice and smooth! Doors seem to line up good together with minimal sag. Thanks again for your advice!

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dirtyjerzy

New Member
Nov 4, 2020
13
N.J.
My stove is from early to mid 70's I believe. I'd is written on bottom of stove with welding rod. It reads either PA1367 or 1361 hard to tell for sure.
 

coaly

Fisher Moderator
Staff member
Dec 22, 2007
4,727
NE PA
Fisher was about 60,000 stoves behind across the Nation with over 30 licensed fabricators making stoves during the oil embargo in the late 70’s. A cold winter was forecast for the East Coast. Bob and Carol flew to Hesston Kansas to make a contract to retool the factory that was making farm equipment and trash compactors. A deal was signed (the day Bob suffered a stroke) and the boxes were mass produced for fabricators across the nation. The H was stamped on the ash fender and you will notice the flue collar is welded on the inside. Fabricators making boxes of their own made boxes in advance and later hung doors, ash fender and vented the way they were ordered, welding the vent pipe on the outside of the finished stove.

A little know fact, as contracts were being sent around the table for all parties and lawyers to sign, Bob pulled out a pen, was so nervous he never clicked it open and signed his name without actually signing the contract. He was too embarrassed to eat on to what he had done. In the flurry of papers, no one noticed. That contract went unsigned.

If this stove was from Michigan, the fabricator with the rights to sell your stove was from “Fisher Stoves” R 131 Box 281 Schoolcraft Michigan 49067.