Suggestion on how to fix edge connector - Page 1
Forum section: electronics / general

author: Ampera
author_rank: Super Contributor
timestamp: March 12, 2018, 03:22:58 am
content: So, I have an AGP card with a missing leaf on the edge connector that goes up into the board where half of the trace it goes into is gone (it's a smaller trace)My question is if there exists some sort of conductive epoxy I could use to patch this (just mask it off, paint some on, and sand it down a bit). I'm just curious if such a thing exists. I don't have good enough resources or skills to give it a fancier repair, with my only other idea is thinning out a piece of lead solder into a leaf, and then somehow applying and binding that to the board, which I think is impractical for various reasons.

author: Rog520
author_rank: Regular Contributor
timestamp: March 12, 2018, 04:31:59 am
content: Could you peel up a trace from a scrap board, cut it to size and then bond it to your card edge? And then connect it electrically to the old trace with something like this:https://www.amazon.com/CircuitWriter-Conductive-Ink-silver-based-4g/dp/B00B88B9KIAnd there is conductive epoxy if you want to give that a try:https://www.amazon.com/MG-Chemicals-Two-Part-Conductive-Adhesive/dp/B008UH4DB2

author: Ampera
author_rank: Super Contributor
timestamp: March 12, 2018, 04:40:15 am
content: I unfortunately don't think lifting a lead from a donor board would work. I might as well use the solder leaf idea.The conductive epoxy seems to be the best idea, but 50 dollars is more than the worth of the card, so. Thanks for the help though.

author: Rog520
author_rank: Regular Contributor
timestamp: March 12, 2018, 05:56:31 am
content: Copper foil tape might also be worth a shot?

author: Ampera
author_rank: Super Contributor
timestamp: March 12, 2018, 06:17:00 am
content: Quote from: Rog520 on March 12, 2018, 05:56:31 amI saw that too, but that might be too thick. Edge connector terminals are just metal leaves. I can make metal leaf, maybe even attack it (somehow), but I believe the main issues will be mechanical strain of the leaf to board bond, and reattaching the leaf to the trace.

author: tooki
author_rank: Super Contributor
timestamp: March 12, 2018, 06:58:23 am
content: Quote from: Rog520 on March 12, 2018, 05:56:31 amThe adhesive isn’t anywherenearstrong enough for a card edge connector. It would shear right off during insertion.Look at PACE Worldwide’s repair videos on YouTube. I’m pretty sure one of them covers this, and IIRC it did involve epoxying on new fingers.

author: ebastler
author_rank: Super Contributor
timestamp: March 12, 2018, 09:22:20 am
content: Collectors of old video games have to deal with this quite often. This guy (http://blog.system11.org/?p=243) recommends glueing on a new contact with superglue, which should be a decent compromise if you don't intend to plug/unplug too often.He surgically removes a contact pad from a donor board, but cutting one from a thin sheet of copper should work just as well if you can live with the non-gold surface. I wouldn't recommend adhesive-backed copper foil, as the adhesive may "creep" under shear stress. You don't want the pad to gradually slide into an adjacent contact...

author: Ampera
author_rank: Super Contributor
timestamp: March 12, 2018, 09:25:34 am
content: Personally I believe if I can find one conductive enough, an epoxy trace is the best possible option. I need one that's cheap and effective (don't we all).I can make a leaf contact if I need to. Tin/lead leaf won't be pretty, but will work. The issue with transplanting a leaf is I am absolutely sure I wouldn't be able to get the TINY (smaller than PCI-e leaves) contacts off another AGP card, and I am even more sure I wouldn't be able to bond it well enough for it to be worth using. My skills and resources simply do not allow for it.I thank everybody for all the help. Doing a bit tight on cash at the moment, but when I get some more money in I'll look into some conductive epoxy. Recommendations that are 15 dollars or under are welcome, though there may be nothing at that price point that would be conductive enough.

author: ebastler
author_rank: Super Contributor
timestamp: March 12, 2018, 09:41:46 am
content: Quote from: TwoOfFive on March 12, 2018, 09:25:34 amI am skeptical about conductive epoxy, especially regarding the mechanical strength of the required (thin and narrow) trace.Come to think of it, maybe your best bet would be to make a little extra room by cutting a short, vertical V-groove where the pad used to be (using a file, Dremel, Xacto knife...), and then glue in a short piece of bare copper wire? You are right, these AGP contacts are awfully narrow -- a thin contact pad will be hard to mount in a stable way. The intrinsic mechanical strength of a wire with a thicker cross section should help to stop it from crumpling upon first insertion, as should the lateral support from the V-groove.