Summary

Everything you need to mount a QU-BD or similar silicone heated bed. Includes bed leveling knobs, spacer with QU-BD bed cut out, and glass sheet clamping system.

Instructions

Print the large spacer parts (A-D). 10% infill is suitable. Assemble the spacer parts and drill four 3mm holes in the aluminium bed using the spacer as a template.
Print the remaining parts at >50% infill for strength.
Insert the bed leveling screws through the aluminium bed and wooden carriage, before screwing on the bed height knobs. They should be a very tight fit.
Assemble four sets of the bed clip pieces as shown in the photo. I had some M3.5 screws with wide heads left over from something else. I also cut down some springs that were laying around.
Push a counter sunk M3 screw through the spacer and drilled holes in the aluminium bed. Line up the bed clip assembly and turn the M3 screw to cut a thread and attach it.
Place silicone heater or heated PCB on top and then a piece of glass. 160 x 170mm is ideal to get some clearance for the nozzle when homing.
Print! (but don't forget to set the z-height screw in a safe position to avoid cracking the now higher glass. Don't forget to alter the bed thermistor setting in configuration.h of the firmware if you haven't used the original. If changing to a faster option, you will find far greater performance by enabling bed PID temperature control in configuration.h on line 161. Flash the firmware, and run bed PID auto tune with:

M303 E-1 C4 S90

This runs bed PID auto tune at 90 degreesC for 4 cycles. The log will spit out PID values when done. Change the PID values on lines 174-176 and re-flash the firmware after this.

Dimensions in mm.

More details at:

http://www.soliforum.com/topic/1819/heated-bed-upgrade-guide-with-picscomparisonsstls/

Solidoodle Silicone Bed Mounting Kit