Electrical – Backlight moving mirror in bathroom

bathroomelectricallightinglow-voltagemirror

Bathroom will have a medicine cabinet behind the mirror. Going to use wall mount sliding door hardware to make the mirror move. Will look similar to this:
https://annporter.wordpress.com/2011/07/28/small-bathroom-design-idea-kitchen-studio-of-naples/
I would like to use some 12v LED lights on the backside of the mirror to give it a nice look like this:
http://www.ikeahackers.net/2013/03/ambilight-enabled-hovet-mirror.html
The transformer will be hardwired
http://shop.ledwholesalers.com/index.php?route=product/product&path=40_110&product_id=149
located elsewhere; not on the back of the mirror.

Question is how can I transfer 12vdc to the moving mirror? I was thinking of 2 metal strips on the top back side of the moving mirror for positive and negative; with some sort of spring loaded contact pins
http://www.asianproducts.com/product/A11357503281461852_P13195330821854652/pin-pogo-pin.html
for power (+-) being centered right below the track. Doable? Better ideas on how to do it? Being discreet is key.

Best Answer

Sliding contact, bathroom, expect failure.

Using a ribbon cable in the manner of a cable carrier (should not actually need a cable carrier, though if you wanted to go there you could get a small one) would be far more reliable. Fixed contacts, cable moves. Seen on many inkejet printer printheads (the "doing it with a ribbon cable method", that is.) The real things are common on CNC tools, equipment with extendable booms, etc.

The "point that's not obvious until you use this method" is that the cable ALWAYS has a 180 degree bend, even at full extension. It leaves the moving part facing away from the fixed part then bends back to the fixed part - the bend moves as the item moves.

cable carrier from WikiPedia