IBM 4704 F107 Restoration
Posted: 13 Jan 2023, 04:53
Part 1
This is description of my process restoring a 1985 IBM F107. For reference this keyboard is from the IBM 4704 terminal computers used at banks in the 1980s. You can find more info on the 4704 keyboards here: http://kishy.ca/?p=648
I have reproduction F77 and love it but also need a full size keyboard with a numpad. This was on my “white whale” wish list and I was fortunately able to get one. This isn’t a guide but I hope you find it useful. I relied on others experience for help and you might also find them useful:
4704 Model F 107-key Restoration Log
[Restoration] IBM 4704 F77 FINISHED
IBM 107 Key Model F 4704 Restoration Thread
IBM 107 Key Model F 6020218 Restoration Work Thread
I’m not the first to do this and hopefully not the last! Without further ado, here we go!
Tools used:
1. Normal size flathead screwdriver
2. Large size flathead screwdriver
3. Clamps
4. Channel lock pliers
5. Hex bit and driver
Items used for cleaning:
1. Denture cleaner or any cleaner good for key caps
2. 90% or greater isopropyl alcohol to clean the PCB
3. Scrubbing pad
4. Sand paper (80 to 100 grit)
5. Toothbrush
Items used for restoration:
1. Rustoleum Rust Reformer (I used black but any color is OK)
2. Medium-Large cardboard box to paint barrel plate
3. Two Blocks to Rest Barrel Plate on for Barrel and Flipper Installation
4. Replacement foam
5. Vertical and horizontal stabilizers for ANSI conversion
I’d recommend replacing the foam if you’re opening the barrel assembly. My F107 was 37 years old and the foam completely disintegrated when I touched it. Not replacing it could cause it to further disintegrate which could cause problems like loose barrels and debris affecting the switch contact.
If you are going to sand and paint the barrel plate then you should plan to replace the foam. I purchased replacement foam from this eBay seller and from Ellipse who executes the New Model F program.
My F107 is original except for an Xwhatsit controller.
First I removed and cleaned the key caps. I only reused the top row numbers keys but wanted to make sure all were clean for storage. I put the keys in a mason jar and cleaned them with denture tabs.
After the denture clean bath I put them in an ultrasonic cleaner and rinsed them.
The keys take a while to completely dry so I left them out for several days. I would recommend putting a fan on them if you want them to dry faster.
Next I unscrewed the case screws which requires a hex bit.
Closeup of hex screw:
Once the screws are off the back case can be removed:
There’s another hex screw holding the cable coming from the controller and after that’s removed the inner assembly can be removed.
The barrel plate was pretty dirty. I suspected the foam was in bad shape, so the barrel plate would need to be removed.
The barrel plate is secured to the back plate with locking tabs that slide together and one that’s bent down onto the back plate.
Sliding locking tabs:
Bent locking tab:
I used a pair of needle nose pliers to bend the locking tab back:
After the locking tab was bent back the barrel plate needed to be pushed away from the sliding tabs. I put a large flathead screwdriver in between the barrel plate and backing plate that rises to secure to the case and twisted to easily push the barrel plate away and slide it from the locking tabs:
I opened the assembly and could see the original foam was in pretty bad shape:
The foam is interesting in how shiny it appears. Closeup of the original foam:
Next I removed all of the flippers and barrels:
I decided to clean the barrels the same way I cleaned the keys using denture cleaning tablets:
I added the tablets first, then the barrels:
Then water to created a nice, bubbly barrel soup:
I let the barrels soak for an hour or so and noticed the foam didn’t completely come off, so I used an old electric toothbrush to remove the remaining foam. I used an old baking tray to keep track of the barrels:
It was tedious and took a long time to clean them all, but the barrels were just like new after:
Then I let them dry near an open window:
Next I had to remove the stabilizers from the barrel plate. I remember reading they are fragile and could break easily and that it was next to impossible to remove them without breaking one and I came close, but did break one using my method. The stabilizers are plastic so I put the barrel plate on a towel to catch the stabilizer after pushing it through with a flathead screwdriver. I used a screwdriver head that perfectly fit into the notch in the back of the stabilizer:
Next I cleaned the barrel plate, running it under water and using a scrubbing pad to remove the remaining foam and debris:
The barrel plate was clean, but showing signs of corrosion and pitting. It needed to be painted so next was sanding to prep for paint.
I used a rough (100-120 grit) sanding block to get the original paint off and any rust.
I kept sanding until you could see mostly metal.
The corrosion was more apparent after the sanding.
I chose Rust-oleom Rust Reformer because I had it laying around in the garage and it seemed like it would work.
I sprayed several coats, waiting a day after each coat based on the experience of another person’s restoration, to ensure a good seal.
After a few coats it looked brand new!
Closeup of the back of of the barrel plate showing the part number?
I then cleaned the foam on the back plate with an alcohol pad.
Along with the PCB. Note: I learned on a Focus keyboard using less than 90% alcohol results in an opaque film on the PCB. I don’t think the film damages the PCB, but I recommend using a higher concentration to be safe.
Next I reinstalled the spacebar stabilizers. These are plastic, old and might not survive the reinstallation, so I recommend having a backup plan. My backup was to use steel spacebar tabs from the New Model F project. These would need to be glued to the barrel plate but would be a good replacement. You could also make your own by bending a small steel tab and gluing it to the barrel plate, or 3-D print a “U”.
https://www.modelfkeyboards.com/product ... tabs-pair/
The F107 spacebar stabilizer wire has a shorter height than the Model M, so I recommend keeping it unless you can install new stabilizer inserts.
The Model M stabilizer wire is thicker, and can’t be used with the original stabilizer inserts:
The original F107 stabilizer is made of several parts, with thicker pieces attached to the end to fit the spacebar.
The thicker piece allows the wire to fit in the original F107 and new Model M spacebars.
I installed the inserts without breaking them by fitting a small flathead screwdriver into the insert and pressing down into the barrel plate.
This is description of my process restoring a 1985 IBM F107. For reference this keyboard is from the IBM 4704 terminal computers used at banks in the 1980s. You can find more info on the 4704 keyboards here: http://kishy.ca/?p=648
I have reproduction F77 and love it but also need a full size keyboard with a numpad. This was on my “white whale” wish list and I was fortunately able to get one. This isn’t a guide but I hope you find it useful. I relied on others experience for help and you might also find them useful:
4704 Model F 107-key Restoration Log
[Restoration] IBM 4704 F77 FINISHED
IBM 107 Key Model F 4704 Restoration Thread
IBM 107 Key Model F 6020218 Restoration Work Thread
I’m not the first to do this and hopefully not the last! Without further ado, here we go!
Tools used:
1. Normal size flathead screwdriver
2. Large size flathead screwdriver
3. Clamps
4. Channel lock pliers
5. Hex bit and driver
Items used for cleaning:
1. Denture cleaner or any cleaner good for key caps
2. 90% or greater isopropyl alcohol to clean the PCB
3. Scrubbing pad
4. Sand paper (80 to 100 grit)
5. Toothbrush
Items used for restoration:
1. Rustoleum Rust Reformer (I used black but any color is OK)
2. Medium-Large cardboard box to paint barrel plate
3. Two Blocks to Rest Barrel Plate on for Barrel and Flipper Installation
4. Replacement foam
5. Vertical and horizontal stabilizers for ANSI conversion
I’d recommend replacing the foam if you’re opening the barrel assembly. My F107 was 37 years old and the foam completely disintegrated when I touched it. Not replacing it could cause it to further disintegrate which could cause problems like loose barrels and debris affecting the switch contact.
If you are going to sand and paint the barrel plate then you should plan to replace the foam. I purchased replacement foam from this eBay seller and from Ellipse who executes the New Model F program.
My F107 is original except for an Xwhatsit controller.
First I removed and cleaned the key caps. I only reused the top row numbers keys but wanted to make sure all were clean for storage. I put the keys in a mason jar and cleaned them with denture tabs.
After the denture clean bath I put them in an ultrasonic cleaner and rinsed them.
The keys take a while to completely dry so I left them out for several days. I would recommend putting a fan on them if you want them to dry faster.
Next I unscrewed the case screws which requires a hex bit.
Closeup of hex screw:
Once the screws are off the back case can be removed:
There’s another hex screw holding the cable coming from the controller and after that’s removed the inner assembly can be removed.
The barrel plate was pretty dirty. I suspected the foam was in bad shape, so the barrel plate would need to be removed.
The barrel plate is secured to the back plate with locking tabs that slide together and one that’s bent down onto the back plate.
Sliding locking tabs:
Bent locking tab:
I used a pair of needle nose pliers to bend the locking tab back:
After the locking tab was bent back the barrel plate needed to be pushed away from the sliding tabs. I put a large flathead screwdriver in between the barrel plate and backing plate that rises to secure to the case and twisted to easily push the barrel plate away and slide it from the locking tabs:
I opened the assembly and could see the original foam was in pretty bad shape:
The foam is interesting in how shiny it appears. Closeup of the original foam:
Next I removed all of the flippers and barrels:
I decided to clean the barrels the same way I cleaned the keys using denture cleaning tablets:
I added the tablets first, then the barrels:
Then water to created a nice, bubbly barrel soup:
I let the barrels soak for an hour or so and noticed the foam didn’t completely come off, so I used an old electric toothbrush to remove the remaining foam. I used an old baking tray to keep track of the barrels:
It was tedious and took a long time to clean them all, but the barrels were just like new after:
Then I let them dry near an open window:
Next I had to remove the stabilizers from the barrel plate. I remember reading they are fragile and could break easily and that it was next to impossible to remove them without breaking one and I came close, but did break one using my method. The stabilizers are plastic so I put the barrel plate on a towel to catch the stabilizer after pushing it through with a flathead screwdriver. I used a screwdriver head that perfectly fit into the notch in the back of the stabilizer:
Next I cleaned the barrel plate, running it under water and using a scrubbing pad to remove the remaining foam and debris:
The barrel plate was clean, but showing signs of corrosion and pitting. It needed to be painted so next was sanding to prep for paint.
I used a rough (100-120 grit) sanding block to get the original paint off and any rust.
I kept sanding until you could see mostly metal.
The corrosion was more apparent after the sanding.
I chose Rust-oleom Rust Reformer because I had it laying around in the garage and it seemed like it would work.
I sprayed several coats, waiting a day after each coat based on the experience of another person’s restoration, to ensure a good seal.
After a few coats it looked brand new!
Closeup of the back of of the barrel plate showing the part number?
I then cleaned the foam on the back plate with an alcohol pad.
Along with the PCB. Note: I learned on a Focus keyboard using less than 90% alcohol results in an opaque film on the PCB. I don’t think the film damages the PCB, but I recommend using a higher concentration to be safe.
Next I reinstalled the spacebar stabilizers. These are plastic, old and might not survive the reinstallation, so I recommend having a backup plan. My backup was to use steel spacebar tabs from the New Model F project. These would need to be glued to the barrel plate but would be a good replacement. You could also make your own by bending a small steel tab and gluing it to the barrel plate, or 3-D print a “U”.
https://www.modelfkeyboards.com/product ... tabs-pair/
The F107 spacebar stabilizer wire has a shorter height than the Model M, so I recommend keeping it unless you can install new stabilizer inserts.
The Model M stabilizer wire is thicker, and can’t be used with the original stabilizer inserts:
The original F107 stabilizer is made of several parts, with thicker pieces attached to the end to fit the spacebar.
The thicker piece allows the wire to fit in the original F107 and new Model M spacebars.
I installed the inserts without breaking them by fitting a small flathead screwdriver into the insert and pressing down into the barrel plate.