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repairing an old (1980) computer keyboard...

DavidMil

New Member
Hello all! I'm new to this sight and I have a question about repairing the PCB on an old Atari 800 computer keyboard. I'm familiar with repairing traces
and replacing through-hole plating, but this is a new one on me. This is a single sided PCB (and keyboard) that I bought on ebay. It said the space
bar didn't work. When it arrived and I looked at it, I saw where someone had tried to do some terrible garage repairs. Evidently they had lifted the pads,
broke the traces and then for some reason tried to drill out the holes with larger drill bits. My question (beside the obvious one of throwing the hole thing out)
is what is the best way to fill in the two holes so I can safely put an eyelet into each them. I'll attach a picture so you can see what I'm talking about. Any
suggestions would be greatly appreciated. My wife suggested Bondo, and I thought about using super glue mixed with dust from other PCB's, but I'd like to
get some ideas from others. I'm retired and do this as a hobby so I'm not trying to make money here. Also there is no stress on the repairs from keyboard use.

Thank you for any suggestions,
David
 

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Ian Rogers

User Extraordinaire
Forum Supporter
Most Helpful Member
You can buy via rivets that may fix this.


You just need to use a conductive paint to connect to the rest of the circiut. ( I used to use car rear demister repair paint )
The paint pen is only about £6...
 

DavidMil

New Member
I can repair the copper traces and I have copper eyelets (via rivets). The problem is that the large hole is 4mm in diameter, and 3.5 mm
from end to end in the oval hole. So I need to fill in the drilled holes enough to allow the via rivets something to attach to. The
oval hole only has a jumper wire through it, so I think I can fill in the hole around an eyelet with a little epoxy glue to hold it
in place. There is no exacting measurements with it as there is with the larger hole.

Thank you for offering your ideas!
David
 

unclejed613

Well-Known Member
Most Helpful Member
there are epoxy sticks, like those used in fuel tank repairs that might work for you... it already has a filler material in it. you break a piece off the stick, mash it up with your fingers to mix it, and fill the holes with it... after it cures, drill new holes the diameter you need
 

KeepItSimpleStupid

Well-Known Member
Most Helpful Member
Actually, you take equal amounts from each end and knead it together, apply, let it harden somewhat. It's best to sand early, it easier. Then let it cure completely.

e.g. https://www.lowes.com/pd/J-B-WELD-WaterWeld-White-Epoxy-Adhesive/3389026?store_code=587


It's probably not worth using fiberglass and hardener?

You should get a hold of some Kapton (Polyimid (spelling)) tape. The stuff is extremely useful. You can bake it at 350F and it comes off easily (the silicon adhesive). You can also get it with an acrylic adhesive.
 

unclejed613

Well-Known Member
Most Helpful Member
Actually, you take equal amounts from each end and knead it together,
there's also a form of it where the hardener is on the outside, and the resin is on the inside concentrically
 

DavidMil

New Member
I want everyone to know that I bought some JB Weld (two part Epoxy) that is good for fiberglass, PVC, Copper, and
Iron. And is not affected by saltwater. It worked beautifully! I appreciate the tip about not letting it get too hard
before sanding too! Anyway, after the epoxy hardened I re-drilled the holes, inserted new eyelets, placed the new
traces, and it looked good. I kinda' messed it up when I put a little too much lacquer over it all, including the existing
traces that I had inadvertently exposed the copper while sanding the epoxy. But all in all it looks ok. More importantly,
it works great! Thank you all for your ideas and support!

David
 

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