A FeatherTouch torsion that actually works

[nine4t4]

I've been having some issues with tension on some locks so I thought I'd like one of those feather touch tools. I've heard all the complaints and thought maybe those can be over come.The Concept is a 10/10, the application of the concept less so. The issues I've come across (in no particular order)
1) too bulky
2) handle kills the feel
3) because of it's weight you're actually pulling off tension
4) doesn't fit in a particular kit
5) doesn't fit smaller locks
6) The handle should be black (really?)

I realized that all I needed was a wrench that was stiff at the working end but that offered more flex at the handle. Ideally, the end result should be as close to a conventional TW as possible. I thought about grinding down some thickness in a wrench. (this softer spot would have been more flexy). But if it bent, the fatigue may soften to breaking. I didn't do the math but a semi-rigid TW seems to complicate the physics of a simple lever.

Then I looked at my BOGEYS. Raimundo's genius is contagious. The spring that holds my bogotas is almost perfect. It's small, it just slips over a tension wrench, it's cheap and easy to find. Although it's intended to spring a pen longitudally. so it's a compression spring, and not a torsion spring (like the Feather touch has), it's still springy laterally. It's not perfect but the levels of torque required as so small they'd be fractions of an ounce per foot.

Take a torsion wrench, cut off about 1 inch from the tail (where your finger would go)
Solder or glue one end of the pen spring to the end that was cut off.
Add about an inch of heatshrink or tape to the new tail end. Enough so that the spring can slide on, but has enough friction to stay in place.
Place the unsoldered end of the spring onto the covered end of the torsion wrench.
Done

You can adjust the sensitivity by sliding the spring up and down the wrench (I need to find a better spring and take pics). Also at the tip deflects the force vector from the finger becomes more glancing and reduces incremental force It's barely longer or wider than the original wrench, little weight has been added, and if it breaks so what?! It costs pennies. The pen spring isn't the best choice but I had one for proof of concept.

I've tried a rough version and it seems to work (I question the placebo effect). It does kill some of the feel, but the odds of hitting the sweet spot increase. On an Abus disc it made a huge difference. On a Master Magnum it was useless ((the return spring is very heavy, which ironically makes it the easiest lock I have to pick. I've had more trouble with 4 pin dollar store locks). It's built like a tank.....with a screen door.)

When it looks like a finished product I'll take some pics. I'd prefer if the end result didn't look so severly macgyvered/ghetto/homebrewed.