Did I ruin my Heatplate, is this repairable?
My Mk3S+ heatbed cable cover became damaged, very very similar as described here.
I was able to successfully extract the cover, but there was plastic bonded to the heat bed. I used a heat gun and removed the bonded plastic. I was happy.
For a moment.
I *then* noticed that the plastic/heatgun process also removed the copper plating on the bed itself.
BEFORE the burned Plastic removal it looked like this: 
After the plastic removal (with heat gun), the copper was also removed and it now looks like this:
Is this recoverable? (Im not an expert, but I'm handy enough with a soldering iron / electronics / etc)?
Or shall I purchase an entire new plate? (which sucks).
Thx.
It's hard to decide from the pictures but I would probably try a home fix expecting about a 50% chance of success...
You are trying to re-establish connectivity with the heating tracks in the print bed; so with a continuity meter do some probing to check which areas of copper are still connected and maybe expose more if necessary; you need a big enough cross section of conductor to carry the current (amperage).
Soldering might leave a raised area where the print-sheet will no longer lay flat but you might try several coats of conductive paint (not the pens) - the stuff sold to repair PCBs for those who can't use a soldering iron, some of the water based ones are surprisingly good; you have to wait for a while to let each coat dry - then I would probably add a square of copper on top as the contact point.
OK, none of this is tested but there is at least a chance of a fix and if it fails the heat beds are still available as spares.
Good luck! Cheerio,
RE: Did I ruin my Heatplate, is this repairable?
I'm not optimistic this can be safely fixed.
The primary reason for the failure was that the cables are mounted below the PCB, and not above. I did this exact same thing and experienced the melting too. I think what ends up happening is this creates a lot of resistance and thus heat. I melted multiple covers before I called customer service and they got me sorted. I'd recommend when you re-assemble, you make sure to mount as shown in the attached image.
Aaron
RE: Did I ruin my Heatplate, is this repairable?
Thanks for the Tip. I definitely will do that. Ordered new heatbed from Printed Solid.