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rpiguy9907

Posted Tue Feb 05, 2019 8:26 pm

A few days ago I posted pictures of a nasty Commodore 128 that I started restoring on Saturday.

Done:
- Case cleaned in dishwasher
- Case painted black
- New metallic 128 label affixed to case
- Keyboard cleaned
- Keycaps retrobrited
- Motherboard cleaned and tested (somehow it works despite all the mods and dirt)

To Do:
- Apply heatsinks to major ICs as this C128 did not come with an RF shield
- Apply new rubber feat

Sad discoveries:
- The F3 and F5 keys stick very badly
- The Enter key on the numb pad sticks very badly
- The clip inside the right hand side of the case was broken so it doesn't close quite flush on that side

Still it is looking a lot better than before and will match the black LCD monitor I intend to use it with.
Attachments
IMG_0217.jpg
IMG_0224.jpg
IMG_1771.jpg

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Mr.Toast
Roseville, CA

Posted Tue Feb 05, 2019 8:49 pm

Such an epic awesome restoration! The black is a very sexy look for the 128, I'm very impressed with how that turned out.

Any painting secrets such as surface prep?

Have you figured out why those keys are sticking?

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G8rduc
North Florida

Posted Tue Feb 05, 2019 8:55 pm

How did you clean each key?

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rpiguy9907

Posted Tue Feb 05, 2019 9:15 pm

Surface prep is not too difficult, I gave it a very quick sanding with a fine sanding block, probably about 5 minutes. I used a gray primer, then three coats of matte black paint. There are some areas that I should leave alone for a couple of days and then wet sand and repaint, but I am probably the only one who notices where lint or dust stuck to the paint so I am going to resist doing that.

Key cleaning starts by putting them all in a Tupperware container with soapy hot water. Why Tupperware? Because you can spin and shake it with the keys inside and it takes more dirt off. Then they go under a faucet and get paper toweled off.

The retrobriting of keys in winter is tough so I seal them in a zip lock bag with 40 percent peroxide and put it into a small aluminum pan. I set them outside and then turn my kettle on. I pour the boiling water over the bag of keys every 30 minutes or so. It really accelerates the process if the sun can’t heat up the keys sufficiently.

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rpiguy9907

Posted Tue Feb 05, 2019 9:21 pm

The keys stick because of bad plungers. To replace plungers you have to take the keyboard mounting plate off of the PCB, which involves removing a ton of tiny screws and desoldering three lock keys, so I am hesitant to try (and lazy, lol).

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intric8
Seattle, WA, USA

Posted Tue Feb 05, 2019 9:40 pm

That boiling tea kettle water idea is interesting.

Have you ever tried just putting the keys in a sauce pan and getting the temp to about 150F? There is a point where you can melt them, of course, so a temperature gauge is what I've seen some folks do.

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rpiguy9907

Posted Tue Feb 05, 2019 10:05 pm

intric8 wrote:That boiling tea kettle water idea is interesting.

Have you ever tried just putting the keys in a sauce pan and getting the temp to about 150F? There is a point where you can melt them, of course, so a temperature gauge is what I've seen some folks do.
I can’t take the fumes that method puts off, plus it is really easy for keys on the bottom to burn, and it is easy to over heat the pot and warp the keys.

If you are super careful, use a pot big enough so no keys sink and they all float, and you don’t mind the fumes, stovetop probably is the way to go for sure.

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Dynamic_Computing

Posted Fri Feb 08, 2019 2:45 pm

I am currently experimenting with fixing a bad plunger on my Commodore 128. I shaved it down so would no longer stick to the sides when the key was inserted. When they plungers develop a crack and you push a key in there it expands the plunger just enough to hit the sides of the little hole. That's what caused it to stick in my case. I took it out and I shaved the sides down of the plunger, and then glued the crack with some nice super glue. that appears to have fixed the sticking issue, but I still have to get that particular key to respond.

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bwldrbst

Posted Fri Feb 08, 2019 6:28 pm

I've been lurking on this forum for a while but I thought I should sign up to point out that the switches on the C128 keyboard look a lot like these or these found in Amiga and quite a few other keyboards.

I recently got my hands on a pretty common Apple M0482 keyboard and was able to replace a broken switch in my A1200. I also swapped the mushy metal springs on the A1200 for the much nicer feeling rubber ones in the Apple keyboard making it far more pleasant to type on.

Cheers,

Andrew

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rpiguy9907

Posted Fri Feb 08, 2019 7:05 pm

bwldrbst wrote:I've been lurking on this forum for a while but I thought I should sign up to point out that the switches on the C128 keyboard look a lot like these or these found in Amiga and quite a few other keyboards.

I recently got my hands on a pretty common Apple M0482 keyboard and was able to replace a broken switch in my A1200. I also swapped the mushy metal springs on the A1200 for the much nicer feeling rubber ones in the Apple keyboard making it far more pleasant to type on.

Cheers,

Andrew
Great tip and you are right the mechanism is identical on the C128 and it can be upgraded with the rubber sleeves. You know you can actually plunder any Mitsumi keyboard with the buckling rubber sleeves, even cheap PC clone keyboards of that era (Mitsumi KPQ-99 boards to be exact).

I could fix the sticky keys by replacing the stems but the C128 has three lock stwictches that are soldered on and I’m too lazy to do it right now.

I’ll add it to the long list of retro projects.





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