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Re: Apples aren't the only fruit.
Posted: 27 Feb 2024 20:46
by stephen_usher
PVA seems to glue properly.
However, it's not as good as first thought.
After redoing five keys two don't work, so the bags are probably not evenly conductive.
Re: Apples aren't the only fruit.
Posted: 27 Feb 2024 21:22
by stephen_usher
Ordered some metalised emergency blankets...
Re: Apples aren't the only fruit.
Posted: 27 Feb 2024 21:51
by rubber_jonnie
Would contact adhesive be better? I Wouldn't have thought PVA would work well with plastic etc.
Re: Apples aren't the only fruit.
Posted: 27 Feb 2024 22:01
by stephen_usher
rubber_jonnie wrote: 27 Feb 2024 21:51
Would contact adhesive be better? I Wouldn't have thought PVA would work well with plastic etc.
Contact adhesive may melt the plastic foam.
Re: Apples aren't the only fruit.
Posted: 27 Feb 2024 23:08
by rubber_jonnie
stephen_usher wrote: 27 Feb 2024 22:01
rubber_jonnie wrote: 27 Feb 2024 21:51
Would contact adhesive be better? I Wouldn't have thought PVA would work well with plastic etc.
Contact adhesive may melt the plastic foam.
Ahh, good point.
Re: Apples aren't the only fruit.
Posted: 28 Feb 2024 18:50
by rubber_jonnie
Just realised I had this:
IMG20240228111852.jpg
Might be something to consider, it's metal tape with adhesive on one side, came with my PGA reballing machine for using to isolate components from heat.
Re: Apples aren't the only fruit.
Posted: 28 Feb 2024 19:23
by PhilC
That tape is quite a low resistance. We use it at work for boiler lagging.
What about conductive painting the surfaces?
Re: Apples aren't the only fruit.
Posted: 28 Feb 2024 20:02
by stephen_usher
I bought some mylar emergency blankets and tried making some pads tonight.
As long as you make sure that the metalised surface is AWAY from the PCB, i.e. on the foam side, they work well. The metalised side is very conductive so it causes a short.
The foil coated foam isn't great, so next stuff to try... weather proofing strip. You can get it as 12mm wide and 3mm thick strips with adhesive on both sides. Stick the mylar to one side and the plastic disc on the other. Well, that's my plan. It's also cheap.
Re: Apples aren't the only fruit.
Posted: 28 Feb 2024 20:04
by stephen_usher
PhilC wrote: 28 Feb 2024 19:23
That tape is quite a low resistance. We use it at work for boiler lagging.
What about conductive painting the surfaces?
The issue is that the keyboard uses capacitance rather than conductance. If you try foil (which I did at first) things go haywire as it bridges the traces and causes a short.
Re: Apples aren't the only fruit.
Posted: 28 Feb 2024 20:15
by PhilC
stephen_usher wrote: 28 Feb 2024 20:04
PhilC wrote: 28 Feb 2024 19:23
That tape is quite a low resistance. We use it at work for boiler lagging.
What about conductive painting the surfaces?
The issue is that the keyboard uses capacitance rather than conductance. If you try foil (which I did at first) things go haywire as it bridges the traces and causes a short.
Ok that makes sense. Good luck with trying to replicate that, I’ll be very interested to hear how you manage it