Has anyone ever tried to fix display cables with 3M 9703 tape? They sent me a sample once, but I need to order some new. I have a little alarm clock with an LCD display that was losing segments; took it apart, found it was connected with the “thermally bonded film connector” — stupid design, very prone to failing. I have a credit-card language translator (eleven languages, even Japanese!) with a failed thermal-film-connector. Franklin products also use the approach, I have a Bookman Bible that’s failed.

So this 3M tape is double-sided, and laced with silver-coated particles that only conduct through the THICKNESS (“z” axis), not across the length or width; works like a “zebra strip”. But being tape, bonds to both surfaces — I can order some 1mm cables (the exact spacing on my clock), solder one end to the PCB, and stick the other end to the glass display with the 3M tape.

I dunno how conductivity would work on oxidized copper traces, but it should be a simple matter to clean them with a “kitchen copper-bottom-pan” cleaner, then maybe use something like “Tinnit” — a two powder solution mixed with water, plates shiny tin onto copper (just dip anything copper in it and it turns silver, makes some really fun pennies!).

http://www.adafruit.com/products/1656

Whaddy’all think???

We’ve talked about that stuff in the past… I think that’s similar to what they used at the factory (which obviously fails over time).

It could probably be used to fix a VB display, but I think you’d want something to continue applying pressure (bracket and foam or something) to prevent it from coming undone again (the datasheet suggests that, and it seems to work best when you press on it).

The other thing I don’t like is that peeling the cable off the display is a bit risky. It’s very thin and tends to curl, and sometimes leaves copper from the cable attached to the display. I think you’d want to chemically remove the old adhesive, rather than simply peeling. But you’d need to make sure you didn’t get any chemical on the clear window. And then you need to line it back up and re-attach.

So… IMO, it’s an inferior fix to soldering, and not any easier. I have some of the tape, and plan to try it if I ever come across another detached display cable, but haven’t yet. If you give it a try, I’d certainly be interested in how it works out.

DogP

I recently worked on a display with a detached cable (not peeled off; it seems to have just fallen off :-?), and I was dreading it, but it was surprisingly easy to solder. Given what DogP mentioned above, it was probably easier than the “Z-tape” would be, and, just like soldering any display cable, it will no doubt last as long as the display and cable themselves with no clamping and whatnot needed.

Although, for the other products you mentioned, which involve attaching a cable to ITO-coated glass contacts, it’s probably a pretty good idea.

BTW, for cleaning the oxidation off of copper, I suggest a fiberglass scratch-brush. I don’t have any experience with Tinnit, but if your copper and its substrate are heat-proof, you could just tin it with a soldering iron and solder.

DogP wrote:
We’ve talked about that stuff in the past… I think that’s similar to what they used at the factory (which obviously fails over time).

It could probably be used to fix a VB display, but I think you’d want something to continue applying pressure (bracket and foam or something) to prevent it from coming undone again (the datasheet suggests that, and it seems to work best when you press on it).

The other thing I don’t like is that peeling the cable off the display is a bit risky. It’s very thin and tends to curl, and sometimes leaves copper from the cable attached to the display. I think you’d want to chemically remove the old adhesive, rather than simply peeling. But you’d need to make sure you didn’t get any chemical on the clear window. And then you need to line it back up and re-attach.

So… IMO, it’s an inferior fix to soldering, and not any easier. I have some of the tape, and plan to try it if I ever come across another detached display cable, but haven’t yet. If you give it a try, I’d certainly be interested in how it works out.

DogP

Interesting — I guess I hadn’t realized they had some kind of conductive adhesive; I thought it was more “stuck on and held in place with hotglue”.

So when the displays are “dead” and submitted for repair — the flex cables still have to be dissolved off of the LED pcb’s?

vb-fan wrote:
So when the displays are “dead” and submitted for repair — the flex cables still have to be dissolved off of the LED pcb’s?

No… when they’re to be soldered, they just need a little bit of the copper of the cable exposed somehow (heat, abrasive, or chemical), so the solder can bridge the connection between the cable and the display. But if you were to use Z-axis tape, you would need to remove the cable from the PCB, since the new tape would have to go between the PCB and the cable.

DogP

RunnerPack wrote:
I recently worked on a display with a detached cable (not peeled off; it seems to have just fallen off :-?), and I was dreading it, but it was surprisingly easy to solder. Given what DogP mentioned above, it was probably easier than the “Z-tape” would be, and, just like soldering any display cable, it will no doubt last as long as the display and cable themselves with no clamping and whatnot needed.

Clearly soldering is the best “fix” — I’ve never used the tape, didn’t know how easy it would be.

Although, for the other products you mentioned, which involve attaching a cable to ITO-coated glass contacts, it’s probably a pretty good idea.

BTW, for cleaning the oxidation off of copper, I suggest a fiberglass scratch-brush.

I saw a post on another forum where a guy was trying to reconnect a glass LCD — but he removed the residue with a knife, and managed to SCRATCH the tin oxide (ruining the connection). I’ve used alcohol, but for aggressive glue lacquer thinner (toluene and methanol) would work if careful.

I don’t have any experience with Tinnit, but if your copper and its substrate are heat-proof, you could just tin it with a soldering iron and solder.

Solder by definition won’t accomplish a glass-smooth surface, to mate with the tape. Tinnit is just two powders dissolved in water, then you submerge copper in it for a few minutes. It’s great when making printed-circuit boards — rinse the ferric chloride off of the newly-made board, then throw it in Tinnit, and all your traces are shiny silver (colored)!

Although, for the alarm clock I made in college, I used nail-polish for “etch resist”, and just left it in place (scratching it off only on the solder-pads). It was cheap clear-red, and looked great.

But I’ll hafta get a girlfriend or wife before I buy nail-polish again! 😯

DogP wrote:

vb-fan wrote:
So when the displays are “dead” and submitted for repair — the flex cables still have to be dissolved off of the LED pcb’s?

No… when they’re to be soldered, they just need a little bit of the copper of the cable exposed somehow (heat, abrasive, or chemical), so the solder can bridge the connection between the cable and the display. But if you were to use Z-axis tape, you would need to remove the cable from the PCB, since the new tape would have to go between the PCB and the cable.

DogP

I guess I hadn’t realized the cable wasn’t totally removed when making the usual “repair”.

So you leave the cable ON the display PCB, and use NaOH to remove a little of the cable insulator and just solder-bridge onto the display PCB. My VB hasn’t died (yet), but I imagine the one I got from ebay needs the repair; I’m pretty good with a soldering iron, I’ll try that!

Thanx!

Here’s a video of someone doing a solder repair, to get an idea of what’s involved: https://www.youtube.com/watch?v=RQC4c9Lylg4 .

You can see that the cable is attached the whole time. In that video, he burned away the coating on the cable. I personally don’t like doing that, as it applies too much excess heat IMO. I originally used NaOH, though anymore I use a fiberglass scratch brush to carefully peel back the lamination, leaving the copper exposed.

You can see pics/details in this post: http://www.planetvb.com/modules/newbb/viewtopic.php?post_id=24012#forumpost24012 .

DogP

DogP wrote:
Here’s a video of someone doing a solder repair, to get an idea of what’s involved: https://www.youtube.com/watch?v=RQC4c9Lylg4 .

You can see that the cable is attached the whole time. In that video, he burned away the coating on the cable. I personally don’t like doing that, as it applies too much excess heat IMO. I originally used NaOH, though anymore I use a fiberglass scratch brush to carefully peel back the lamination, leaving the copper exposed.

You can see pics/details in this post: http://www.planetvb.com/modules/newbb/viewtopic.php?post_id=24012#forumpost24012 .

DogP

Thanx, Dog — very helpful!

Yeah I know what you mean about “too much heat”; gave me the willies on that you-tube video seeing how long he had the soldering iron on the board; either the temp was set very low, or he was lucky not to start lifting traces. And I woulda brushed away most of the solder before using wick, you use less wick. I just bought a kit that has a couple of very-fine pitch IC’s (one a PLCC, the other dual inline); solder wick is the only way I can imagine soldering it. Steamed that he sent those two chips in a non static-protected pouch…

PS — where does one get a “fiberglass brush”?

vb-fan wrote:
PS — where does one get a “fiberglass brush”?

They used to be easy to find (I had gotten them at Radio Shack and the auto parts store)… but in the last few years, it seems that most have either gotten rid of them (or, in the case of Radio Shack – gone out of business), or changed to a nylon bristle brush (still calling them “fiberglass”). The nylon brush is completely useless.

The last one I bought came from an art supply seller on ebay (who I just checked isn’t selling on ebay anymore). But again, you gotta make sure it’s actually fiberglass and not nylon.

DogP

vb-fan wrote:
PS — where does one get a “fiberglass brush”?

I recently (a month ago) purchased one of these, and, although they used “nylon” in the title, I actually received a fiberglass one. Actually, I asked the seller if he was selling fiberglass or nylon, and he said the “nylon” in the title was a mistake that he was going to fix… he obviously never fixed it, but I got an actual fiberglass brush, so it’s worth a try.

Good evening DOGP
Do you still repair any virtual boy system.?after reading all your miracle work i was wondering if you could do a miracle with mine?it a bad case of glitchy line one one side and also seeing double.hope you can help

my email malicedoll79@gmail.com
thank you

Malicedoll79 wrote:
Good evening DOGP
Do you still repair any virtual boy system.?after reading all your miracle work i was wondering if you could do a miracle with mine?it a bad case of glitchy line one one side and also seeing double.hope you can help

my email malicedoll79@gmail.com
thank you

Sorry… unfortunately, I don’t do repairs anymore. Both RunnerPack (USA) and TheForce81 (Netherlands) offer repairs, and do great work though… so I’d message one of them (depending where you live).

DogP