Green residue?

[espruino-discuss]

Posted at 2025-01-14 by DanTheMan827

A green residue keeps appearing on the rf shield over time on my puck.js, has anyone else had this happen? What is it?

It cleans off easily with isopropyl alcohol

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Attachments:

• IMG_0303.jpeg

[espruino-discuss]

Posted at 2025-01-14 by @gfwilliams

That's an odd one - I've never seen that before! Does it clear off completely? It looks like corrosion, so you'd expect that the metal shield might look a bit damaged after.

Is there a possibility that the PCB inside is getting damp at all?

And is this the Puck of yours that went through the washing machine 3 years ago? https://forum.espruino.com/conversations/358498/ It looks like it's the same revision.

If so, I'd make sure you give it a really good rinse out with water (maybe leave it to soak for a bit) and make sure it's left for a week on a radiator to really dry out. It's probably still got some of the detergent in it

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Posted at 2025-01-14 by @yerpj

I've always seen this same deposit on the puck after some time inside the silicon cover. As far as I can tell, no damage inside the module. Sometimes I clean it but to be honest I do not take this too seriously. You can add some tape on the RF shield to isolate it from the silicon cover it should protect it

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Posted at 2025-01-15 by @gfwilliams

Wow, that's really strange - out of interest what colour covers do you use? maybe there was some manufacturing residue left on them?

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Posted at 2025-01-15 by @yerpj

I am mostly using the red ones

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Posted at 2025-01-17 by DanTheMan827

No, that puck isn’t the same one that went through the washing machine, I got another… although that one still does work albeit with a busted battery holder… that got repurposed as a uart dev board.

Yes, the green stuff cleans off with isopropyl and there isn’t any damage to the shield afterwards.

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Posted at 2025-01-17 by @gfwilliams

Thanks - it's really strange - what colour case are you using @DanTheMan827?

Maybe you could try washing out the inside of the case in case there's something in there that's causing the corrosion. You could check the battery around the seal in case maybe it has leaked?

I've got tons of Pucks kicking around here and I can't say I've ever noticed this happening here...