Tool1 was design to make use of a 17mm spanner or a 6mm hex key to give leverage on those stubborn bolt.
Usually the crank bolt are hand tight and thus Tool2 is good enough for the job.
Tool3 can be printed without any support.
Use whichever tool you prefer to tighten the crank arm so that it has no free play yet not so tight that it pressed hard on the bearings.
Tool1.stl | 164.3KB | |
Tool2.stl | 188.4KB | |
Tool3.stl | 670.8KB |