Grandma Firebrick and Install Questions

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NewOld

New Member
Jan 20, 2020
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Oregon
Since the Everything Fisher thread has so much hard to find information, I'll start a thread with detailed info on each model as I put it together.​
Anyone needing information on their Grandma or Grandpa double door stove is likely to find it here. Please ask if you don't find what you need !​
Grandma UL Unlisted pre 1980 with 2 square doors;​
Width ; 25 1/2" across top plate.​
Depth ; 28 1/4" overall with ash fender (shelf)​
Height ; 30 1/2" rear, 24 1/2" front​
Approx. weight 406 pounds​
Logs to 20" across stove​
Heats approx. 1500 s.f.​
Requires 5 bricks across back, 4 sides​
Flue size 8 inch top or rear​
Door opening ; 17" wide X 10 1/2" high​
Measurements from original 1977 prints, weight from ad; Dec. 1979​
Grandpa UL Unlisted pre 1980 with 2 square doors;​
Width ; 29 1/2" across top plate.​
Depth ; 30 1/2" overall with ash fender (shelf)​
Approx. weight 454 pounds​
Logs to 24" across stove​
Heats approx. 2000 s.f.​
Requires 6 bricks across back, 4 sides​
Flue size 8 inch top or rear​
Door opening ; 22" wide X 11" high​
Measurements from original 1977 prints, weight from ads; 1978​
The first double door stoves were made in Oregon in 1976. Jake Jackson was a neighbor (his stove patent has his address very close to Bob) and he asked Bob to build him parts for an outdoor barbeque. After the project, he ended up selling Jake a license to build Fisher Stoves in Redmond OR, and loaned him $1000 for his first steel order. Jake later had a customer want a double door stove to view the fire, and brought the idea to Bob Fisher's shop. Bob wanted no part of more cast door patterns, and knew the stove wouldn't be as efficient as his 6 inch vented single door stoves. Public demand (and Bob's wife Carol) caused the need for a "Fireplace Model". Bob took a ride to Redmond and found Jake selling an adaptation of his stove with double doors. They agreed to terminate his license to build Fisher Stoves after Jake fulfilled his stove orders. This wasn't far from Springfield where they both lived, and Bobs "factory" was now in Eugene. So that's where the first ones were produced. Jake went on to build the Frontier Stove line and their friendship lasted until Jake's death many years later. Fisher called the new line the "Fireplace Series". These have an 8 inch outlet compared to the single door "Bear Series" 6 inch outlet stoves. Available in top or rear discharge, best for placing the rear outlet type on a hearth exiting up the existing flue.​
The Grandpa Bear was the largest at the time, only one other Fisher model, the XL was ever made larger.Grandpa measures 29 1/2 inches across the top plate, with the box measuring 28" wide X 23" deep. Comfortable heating 2000 s.f. as suggested in Fisher literature, the stove is capable of even more.​
The first stoves had stars on the doors, and a 76 in the largest star on the right door. Like all other Fisher Stoves with solid cast iron doors, they do not use gasket material for a door seal ! The first door hinge ears were not drilled completely through for the common 3/8 round head rivet used as a hinge pin. These had a pressed in pin pressed into the bottom of the door hinge ear, so the doors could be lifted off without loosing pins, since the idea of double doors was to be able to view the fire with the use of a fire screen attached to the front of the stove.​
In July of 1977 a revision was made for adding a rear and bottom heat shield made of 20 Ga. Cold Rolled Steel. This was designated as a model II on the prints. A notation on the drawing states the shields are not required when installed on a hearth in front of a fireplace.​
In 1979 a Roman Numeral III was added and the door style was available in the original square with flat top, OR with a new arched top style, called "Cathedral". UL Listed stoves from 1980 on had integral shields with bent corners instead of welded angle iron corners that became the legs. A baffle was added for smoke reduction and optional nickel or brass plated doors became available in the cathedral style in 1980 until end of production in 1988.​
Many fabricators continued to produce the old style stove with angle iron corners that was not UL Listed $100 cheaper than the Listed model for installation on non combustible hearth.​
Leg options became available in 1980 shown in brochure as Straight, Furniture, and Bear Leg below;​
The III was later offered with Brass and Glass, and later the Model IV with larger glass was added..​
Attached Files:
Early 76 Grandpa, Pre 1980 Grandpa,
Metallic Brown Grandma III, Grandma IV (with larger glass)

View attachment 64924View attachment 64925View attachment 64926View attachment 64927
The posts are so old on here, not sure if I will get a response. I have a Grandma Fisher that has no firebrick, what size do I need and where do I buy it? Do I have to set it 36 inches from all sides?
 
The posts are so old on here, not sure if I will get a response. I have a Grandma Fisher that has no firebrick, what size do I need and where do I buy it? Do I have to set it 36 inches from all sides?
The posts are so old on here, not sure if I will get a response. I have a Grandma Fisher that has no firebrick, what size do I need and where do I buy it? Do I have to set it 36 inches from all sides?
Standard size thin firebrick. They are about 1.25"thick. And yes you need 36" from combustibles unless you do a proper ventilated heat sheild
 
Standard size thin firebrick. They are about 1.25"thick. And yes you need 36" from combustibles unless you do a proper ventilated heat sheild
If I install a fire shield on the back wall shouldn't I be able to put it closer to the back wall? What size would the hearth have to be?
 
If I install a fire shield on the back wall shouldn't I be able to put it closer to the back wall? What size would the hearth have to be?
Not a fire sheild. A ventilated heatsheild as spelled out in nfpa211 for unlisted stoves. If done correctly it will give you a 2/3 reduction in clearance. Which means 12". The hearth needs to be 18" on all sides.

It is all clearly spelled out in nfpa 211
 
The posts are so old on here, not sure if I will get a response. I have a Grandma Fisher that has no firebrick, what size do I need and where do I buy it? Do I have to set it 36 inches from all sides?

What Grandma Bear do you have? The older style with flat top doors, or the newer Grandma III with a rear heat shield and no angle iron down the corners?
The Grandma III has brick layout in the manual.
There are threads for both with brick diagrams. I'll link you to the one you need to follow.

The threads in the sticky section serve as an information source and most join to start a new thread with specific questions. I'll give you your own thread so as you go, more questions can be asked and found easily. Welcome to the Forum!

The cheapest place to buy firebrick is a local masonry supply store. They can be found for about $1.50 each there. Ace Hardware, some Tractor Supply and online sources are much more. They will be 4 1/2" wide X 9" long and 1 1/4" thick.
 
This article is very helpful and explains heat shield, and how to make one UL compliant.


Specifications are derived from NFPA 211 that you should become familiar with for other venting and installation safety factors of solid fuel burning appliances.

You will find in NFPA 211, a "fire shield" such as solid brick in contact with a combustible wall only allows a clearance reduction of 33% compared to the 66% reduction with a ventilated heat shield. This is listed in the section for unlisted appliances. (non-UL)
If you have the Series III Model or above, it will have a UL tag on the back specifying clearances. If no tag, revert to the NFPA 211 specs allowing 36 inches to combustibles, down to 12 inches with proper heat shield.
 
Not a fire sheild. A ventilated heatsheild as spelled out in nfpa211 for unlisted stoves. If done correctly it will give you a 2/3 reduction in clearance. Which means 12". The hearth needs to be 18" on all sides.

It is all clearly spelled out in nfpa 211
Sorry I have no idea where to find info on Napa 211 and I haven't had a stove for 20 years. After no power in freezing weather last year I'm more than ready to get this one going. BTW what is the value of my stove?
 
Sorry I have no idea where to find info on Napa 211 and I haven't had a stove for 20 years. After no power in freezing weather last year I'm more than ready to get this one going. BTW what is the value of my stove?
Found the link, thank you. Now I see the door does not close tight, what do I need to do to remedy this?
 
What Grandma Bear do you have? The older style with flat top doors, or the newer Grandma III with a rear heat shield and no angle iron down the corners?
The Grandma III has brick layout in the manual.
There are threads for both with brick diagrams. I'll link you to the one you need to follow.

The threads in the sticky section serve as an information source and most join to start a new thread with specific questions. I'll give you your own thread so as you go, more questions can be asked and found easily. Welcome to the Forum!

The cheapest place to buy firebrick is a local masonry supply store. They can be found for about $1.50 each there. Ace Hardware, some Tractor Supply and online sources are much more. They will be 4 1/2" wide X 9" long and 1 1/4" thick.
Well the model # shows H 419587 and it has square doors with a heat shield in the back and the bottom..I can post a pic of the back if needed..
 
Fisher used no model numbers. Square doors means it is pre 1980. Models made then with double doors would be Grandma or Grandpa.
The H means it was probably built buy Hesston in Kansas, and that would be the serial number.
If the outlet pipe is welded inside the stove, that confirms it was made by Hesston Corp.

The door seal is the channel iron welded to stove front. Clean the back of the doors and clean door seal with a wire wheel in drill if necessary. It was built to seal with metal to metal contact, no gasket material was used. Pictures are necessary to further identify it. (probably a transition stove built around 1979 between the I with no shields, to a II with bolt on shield, or III with integral shields).

There are no book values for classic stoves. Price is whatever buyer and seller agree upon. If it is a UL listed stove, it is worth more since that can be legally installed in other states, but no wood stove is legally sold or installed in your state without being an EPA Certified stove since 2009.
 
Fisher used no model numbers. Square doors means it is pre 1980. Models made then with double doors would be Grandma or Grandpa.
The H means it was probably built buy Hesston in Kansas, and that would be the serial number.
If the outlet pipe is welded inside the stove, that confirms it was made by Hesston Corp.

The door seal is the channel iron welded to stove front. Clean the back of the doors and clean door seal with a wire wheel in drill if necessary. It was built to seal with metal to metal contact, no gasket material was used. Pictures are necessary to further identify it. (probably a transition stove built around 1979 between the I with no shields, to a II with bolt on shield, or III with integral shields).

There are no book values for classic stoves. Price is whatever buyer and seller agree upon. If it is a UL listed stove, it is worth more since that can be legally installed in other states, but no wood stove is legally sold or installed in your state without being an EPA Certified stove since 2009.
Ok to clarify, and I apologize for the confusion Im in the middle of multiple projects. The stove is a newer Grandma as the doors are arched on top, not square, there is a 1 1/2 in air space between the stove and shield on the back and bottom. The door seems to loosen up after its shut and I pull it with my finger. So does it need a seal or do I readjust the door? Someone apparently removed one stove bolt from each door and installed standard bolts instead. The exhaust vent is welded on..the pic of the back does not reveal the air gap it just looks solid but its not.
 

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Note that the firebricks you need are commonly called "splits" since they are half the thickness of a standard brick.
 
I'd like to see a picture of the door bolts. Doors hinge pins were originally rivets 3/8" x 1-3/4". I buy replacements from eBay.
Unless the door hinges are completely worn out you do not need a gasket. The stove was designed not to have one.
 
I'd like to see a picture of the door bolts. Doors hinge pins were originally rivets 3/8" x 1-3/4". I buy replacements from eBay.
Unless the door hinges are completely worn out you do not need a gasket. The stove was designed not to have one.
Added two pics of the inside that shows the brackets to hold the brick. My understanding is 4 on each side 5 in the back
 

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Forget how I identified an older stove with flat top doors.
You have a Grandma III with integral shields made after 1980.
The Series III manual in sticky section has the brick layout in it.
The manual also has clearances and floor protection requirements.
fischermanual.pdf

The sealing area in center of channel iron looks clean.

The hinge pins shown installed at the top right and bottom left are correct.
You can get new, or I can walk you through how to easily make your own if you have a drill and bench grinder.
If there are threads on those bolts, do not use or move doors since it will wear the holes quickly. When you have correct hinge pins, grease the hinge pins with high temp grease or silver anti-seize.

Close the doors and latch the right side latch. The left door latch handle should not move.
Give us a picture of the doors closed and latched. We're looking for the angle of the door handles. (they should match, positioned at the same angle when latched) We can tell you if they are correct or if the latch rod needs adjusting, and how to do it.

When bricking a stove, vacuum or brush every thing out of the stove interior so absolutely nothing can get between the bricks as they are installed. Install bottom layer, rear wall, then sides finishing at front.
No pieces of brick or ash can be between any when installing. Any spaces will fill in with ash making them tight. Always burn on an inch of ash when removing ash.
 
Forget how I identified an older stove with flat top doors.
You have a Grandma III with integral shields made after 1980.
The Series III manual in sticky section has the brick layout in it.
The manual also has clearances and floor protection requirements.
fischermanual.pdf

The sealing area in center of channel iron looks clean.

The hinge pins shown installed at the top right and bottom left are correct.
You can get new, or I can walk you through how to easily make your own if you have a drill and bench grinder.
If there are threads on those bolts, do not use or move doors since it will wear the holes quickly. When you have correct hinge pins, grease the hinge pins with high temp grease or silver anti-seize.

Close the doors and latch the right side latch. The left door latch handle should not move.
Give us a picture of the doors closed and latched. We're looking for the angle of the door handles. (they should match, positioned at the same angle when latched) We can tell you if they are correct or if the latch rod needs adjusting, and how to do it.

When bricking a stove, vacuum or brush every thing out of the stove interior so absolutely nothing can get between the bricks as they are installed. Install bottom layer, rear wall, then sides finishing at front.
No pieces of brick or ash can be between any when installing. Any spaces will fill in with ash making them tight. Always burn on an inch of ash when removing ash.
The left door closes perfectly the right drops lower and the handles are not positioned the same. I have a drill and a grinder
 

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Forget how I identified an older stove with flat top doors.
You have a Grandma III with integral shields made after 1980.
The Series III manual in sticky section has the brick layout in it.
The manual also has clearances and floor protection requirements.
fischermanual.pdf

The sealing area in center of channel iron looks clean.

The hinge pins shown installed at the top right and bottom left are correct.
You can get new, or I can walk you through how to easily make your own if you have a drill and bench grinder.
If there are threads on those bolts, do not use or move doors since it will wear the holes quickly. When you have correct hinge pins, grease the hinge pins with high temp grease or silver anti-seize.

Close the doors and latch the right side latch. The left door latch handle should not move.
Give us a picture of the doors closed and latched. We're looking for the angle of the door handles. (they should match, positioned at the same angle when latched) We can tell you if they are correct or if the latch rod needs adjusting, and how to do it.

When bricking a stove, vacuum or brush every thing out of the stove interior so absolutely nothing can get between the bricks as they are installed. Install bottom layer, rear wall, then sides finishing at front.
No pieces of brick or ash can be between any when installing. Any spaces will fill in with ash making them tight. Always burn on an inch of ash when removing ash.
I learned from this forum I need brick on the sides and back but didn't realize I needed them on the bottom too. I will definitely clean the stove before installing bricks the seller sold it to me dirty at $200. I want to thank you for all the help, you're a great help to me.
 
Your door latch rod is wayyyy out of adjustment.

If you have a propane torch you can get the rod on the back side of the door hot enough to bend. It should glow a dull red. Heat the bend of the latch rod where it should be close to a 90* angle to latch on the other door when closed. Yours has straightened out over time and being over tightened. (people tend to push down on the door handle, but it is not necessary to tighten it more than necessary) It needs to be bent into a sharper angle. No more than 90* angle. If you bend it cold, which can be done without too much force, they tend to go back when heated with a normal fire. Bend It hot, and it will stay there. I use an adjustable wrench to bend when hot without too much force when hot enough.
Handles should be in this position when done;

GM III Before Adjustment-001.jpg Before GM III After Adjustment-001.jpg After

Bricks protect the steel plate from intense heat and reflect heat back into the firebox causing a hotter and cleaner burning fire.

It depends on how the brick retainers were put in for the bottom brick placement.
If a brick standing up the 9 inch height fits under the brick retainer and sits on the stove bottom, it was made to install side and back first, then fill in with bottom bricks to hold the sides tight. If the retainers measure 10 1/4 or more inches up off the bottom, the bottom bricks go in first as shown on diagram in manual. Some fabricators lowered the brick retainers so the side and back bricks can go in first, then the bottom layer holds them tight to the walls to prevent movement and breakage in shipment. They were originally designed to be shipped without brick, installing on site when in place.
I like to wet a cloth and wipe the stove out to remove any loose ash or brick crumbles. It only take a tiny piece of anything to make getting the last one in a row into place. Sometimes they fit perfectly tight. A touch of grit between them, they just don't fit. Wear gloves, once you do it, it's not a difficult thing.

To make your own hinge pins;
Find a 3/8 bolt with no threads from the head down to the length you need. (your existing bolts may be fine if they have a shank without threads) Grind the hex points off until round.
Next chuck the bolt in drill and run in reverse. Turn on bench grinder and grind the bolt head to a round shape with drill turning slow in reverse. This will shape the head round like a round head machine screw or rivet head. (they should match the 3/8 rivets you have for the correct hinge pins) With a little practice you will end up with a round head hinge pin.
 
Your door latch rod is wayyyy out of adjustment.

If you have a propane torch you can get the rod on the back side of the door hot enough to bend. It should glow a dull red. Heat the bend of the latch rod where it should be close to a 90* angle to latch on the other door when closed. Yours has straightened out over time and being over tightened. (people tend to push down on the door handle, but it is not necessary to tighten it more than necessary) It needs to be bent into a sharper angle. No more than 90* angle. If you bend it cold, which can be done without too much force, they tend to go back when heated with a normal fire. Bend It hot, and it will stay there. I use an adjustable wrench to bend when hot without too much force when hot enough.
Handles should be in this position when done;

View attachment 255700 Before View attachment 255701 After

Bricks protect the steel plate from intense heat and reflect heat back into the firebox causing a hotter and cleaner burning fire.

It depends on how the brick retainers were put in for the bottom brick placement.
If a brick standing up the 9 inch height fits under the brick retainer and sits on the stove bottom, it was made to install side and back first, then fill in with bottom bricks to hold the sides tight. If the retainers measure 10 1/4 or more inches up off the bottom, the bottom bricks go in first as shown on diagram in manual. Some fabricators lowered the brick retainers so the side and back bricks can go in first, then the bottom layer holds them tight to the walls to prevent movement and breakage in shipment. They were originally designed to be shipped without brick, installing on site when in place.
I like to wet a cloth and wipe the stove out to remove any loose ash or brick crumbles. It only take a tiny piece of anything to make getting the last one in a row into place. Sometimes they fit perfectly tight. A touch of grit between them, they just don't fit. Wear gloves, once you do it, it's not a difficult thing.

To make your own hinge pins;
Find a 3/8 bolt with no threads from the head down to the length you need. (your existing bolts may be fine if they have a shank without threads) Grind the hex points off until round.
Next chuck the bolt in drill and run in reverse. Turn on bench grinder and grind the bolt head to a round shape with drill turning slow in reverse. This will shape the head round like a round head machine screw or rivet head. (they should match the 3/8 rivets you have for the correct hinge pins) With a little practice you will end up with a round head hinge pin.
Don't have a torch and the stove is in the house so running propane inside is not something I want to do especially with so many chemical sensitivities. Might be able to get help to move it to the front door and find a torch somewhere. Looks like the bolt on the right door is smaller in diameter then the left one so maybe it hasn't ruined the hole size. I will replace both of them either by modification or buy new.
 
Don't have a torch and the stove is in the house so running propane inside is not something I want to do especially with so many chemical sensitivities. Might be able to get help to move it to the front door and find a torch somewhere. Looks like the bolt on the right door is smaller in diameter then the left one so maybe it hasn't ruined the hole size. I will replace both of them either by modification or buy new.

The latch rod you need to bend is on the right door. You can remove it to heat outside if that is a problem. I do them on the stove to try closing before it cools down in case it needs to be tweaked a few times to get just right. No worse than soldering a pipe inside. Actually less smoke without soldering flux. Connector pipe is going to smoke off a lot worse than heating an inch of 1/2 rod. If you heat the door latch rod after hooking up to pipe and chimney, burn some newspaper in the stove to start a draft. Air, smoke and impurities in the house is drawn up the stack with doors open like a vent fan. Same as removing ash. Do it with a hot chimney and fly ash rushes into stove and up stack. The chimney is your vacuum cleaner.

Make sure the bolts you use are 3/8 with smooth shank from head to length needed and cut the threads off, or cut to the same length as the original hinge pins you have. You can practice grinding on an old bolt to get the hang of making round heads look right. Keep greased to prevent wear.
 
The latch rod you need to bend is on the right door. You can remove it to heat outside if that is a problem. I do them on the stove to try closing before it cools down in case it needs to be tweaked a few times to get just right. No worse than soldering a pipe inside. Actually less smoke without soldering flux. Connector pipe is going to smoke off a lot worse than heating an inch of 1/2 rod. If you heat the door latch rod after hooking up to pipe and chimney, burn some newspaper in the stove to start a draft. Air, smoke and impurities in the house is drawn up the stack with doors open like a vent fan. Same as removing ash. Do it with a hot chimney and fly ash rushes into stove and up stack. The chimney is your vacuum cleaner.

Make sure the bolts you use are 3/8 with smooth shank from head to length needed and cut the threads off, or cut to the same length as the original hinge pins you have. You can practice grinding on an old bolt to get the hang of making round heads look right. Keep greased to prevent wear.
Didn't even think about removing the door! Will look for a torch…can't do it with fire, no pipe is installed yet and need to build a heat shield for the wall as well as a hearth. My pipe is all double walled 6" so will need an adapter at the stove top.
 
Didn't even think about removing the door! Will look for a torch…can't do it with fire, no pipe is installed yet and need to build a heat shield for the wall as well as a hearth. My pipe is all double walled 6" so will need an adapter at the stove top.
What chimney is it going into?
 
No chimney, it's just double walled pipe thru the ceiling and roof….
Double wall chimney pipe or double wall stove pipe?