Just wondering if anyone here is familiar with the Fitbit Zip, and if you are how are they molding this part (the front housing)?
There are no seams where the LCD window is, and the whole part is highly glossy. I’m assuming they are molding the color, they overmolding a clear plastic (PC, or similar?).
I’m working on a project, that is a totally different application, but a similar size and having similar internals (PCB, LCD, battery, touch sensors). The Fitbit is 28mm x 35.5mm x 9.65mm
If it isn’t an overmold, could this be done as a secondary paint process, or in-mold decoration; at this size, and having a nice clean window left behind??
There is a back housing that looks to be molded slightly differently (it is usually covered by the flexible case), but couldn’t find a good photo.
Hard to be sure with these photos but I think you may be right on the in-mold decoration guess.
They might be using a colored in mold graphic with a cutout for the LCD under a clear polycarbonate or copolyester.
Back painted clear plastic, and a mask for the LCD? If the ‘Fitbit’ graphic look elevated off the surface I would guess that.
Thanks for the replies. I may have to buy one and tear it apart!
Guessing the following:
Backscreened Makrolon film, polycarbonate.
Pressure formed to shape.
Injection overmolded for exterior cosmetic and structure.
Thanks NXAKT, I’m leaning towards it being IMD as well.
I’m surprised FitBit didn’t do more with the opportunity to add some nice subtle graphic elements to the body color, rather than just the neon colors and a logo? Especially since I imagine you pay an upcharge for IMD, over painting??
Unless they went with the IMD to be able to screen the capacitive button circuit to the back side of the IMD substrate. I know Serigraph has the capability to do that.