Freewheel removal tool FR-1.2 (this doesn't work!)

thingiverse

This is my attempt at making an FR-1.2 freewheel removal tool for a bicycle. The model has very accurate dimensions, however the torque required to remove a freewheel is much higher than the shear force of the material. First attempt was with pla, printed hollow to save on time, and printed in the vertical position. It went into the wheel with a few taps from a hammer. With the application of force, the teeth did not slip, but the material broke. Using a dremel, I removed the remnants from the wheel. For the second attempt I used ABS and printed in the horizontal orientation for improved strength. I made the model solid for this attempt. I was able to apply a lot more force, however the material still broke. Conclusion - This tool is not yet feasible with current materials. The torque required to remove a freewheel is too high and requires a tool made from steel. Luckily, the tool can be found for about $5 on ebay. Unfortunately you will have to wait awhile to get it (I was impatient so I tried making my own). Models include hollow and solid versions of 1" socket and square tools. ** edit 1 ** Edited the model to use two M4 bolts today. The bolts sheared. Use bigger bolts of hardened material?