prusa i3 Zonestar p802/Anet A8 Y idler

updated Y idler with M3 screw thread tensioner

the fit between carrier and tensionier is very tight, so some sanding will be required, however it works well and has no movement when in use.

I printed the carrier with supports, with the 4 location lugs facing up.

I have put screw holes in the base to allow attachment to a wooden board, I'll also be uploading a set of mounting blocks for the M8 threaded rods to attach them to the board (now here http://www.thingiverse.com/thing:1305674)