Bare Bones...


BOK – Radius and Ulna


Bare Bones has maintained a dislike towards BOK wiper tension wrenches since the beginning, but after enough pressure and inquiries, we have added the ‘Radius and Ulna’ (named by ‘TheGreenishOne’ given the similar ‘twist’ in the same named human bone). Its available in two sizes suitable for pin tumblers (3.5mm wide) and dimple locks (4.1mm wide).
Most locksporters agree that a 90-degree twisted BOK wiper tension tool provides poor feedback and dampens tension to the core. Its for this reason, majority of BOK wiper tension wrenches sold by manufactures use the sharp right-angle profile.
So what happens if you fully twist one end by 360 degrees? It improves the feedback compared to a 90-degree twisted profile as the dampening effect is now reduced (full twist provides equal strength in all directions and therefore equal feedback) but still provides some flex compared to the sharp right-angle profile. As a bonus, left/right tension direction or left/right-handed use is identical for feedback.
It seems an easy choice then to provide both the sharp right-angle profile at one end and a fully twisted profile at the other! Great! So how else can we improve BOK wiper tension? By increasing the length of the tool, we can improve control over the torque (as ‘Torque Formula’ can be a simplified to be  – 2 times Force times Distance). A ‘main body’ length of approximately 100mm plus the length of each profile seems a pretty good starting point.
Not really interested in the ‘Radius and Ulna’ and prefer to make your own? No problems. The same 304 stainless steel will be made available in flat lengths to make your own design or small finger picks.
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Additional information


3.5mm width to suit Pin tumbler lock, 4.1mm width to suit Dimple locks


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