Seeking info about "Letter Box-Type Tension Tools"

[jbrau]

I was browsing the HPC site and noticed these Letter Box-Type Tension Tools http://www.hpcworld.com/Picks/p_lrboxt.htm. I've never seen them used nor heard about them, but it appears that they would give you some torque, yet lots of space to work in the keyway. Anybody with experience, please let me know how well they worked, and any less-than obvious caveats. Thanks!

[EvoRed]

They slot in the bottom/top of the keyway in front of the first pin and I personally use mine quite a lot, they work very well. Being so small I'm forever putting them down and leaving them on site though...

[MeisBarry]

I'm not quite understanding the picture on that site and don't really see how it's used. Is it for normal pin cylinder locks?

[mh]

I'm not quite understanding the picture on that site and don't really see how it's used. Is it for normal pin cylinder locks?

The tension tools shown (TEN-2 - TEN-5) consist of 3 parts, from the bottom left to the top right:

..........3
122223
1
1
1
1

You grip it at 1;
2 is parallel to the axis around which the plug should turn;
3 goes into the keyway.

It's useful if a small tension tool can't grip the plug properly.

3 is however obstructing the keyway a little bit, that's why you place it in front of the 1st pin, as EvoRed explained.

[MeisBarry]

Alright I think I see. '3' would be parallel to to the pins and next to the first. Makes sense.

[jbrau]

3 is however obstructing the keyway a little bit, that's why you place it in front of the 1st pin, as EvoRed explained.

Interesting, I thought 2 went along the bottom of the keyway and 3 went up behind the last pin, which is an application I'd like to try. Given that it wouldn't be easy for me to buy one of these HPC tensioners anyway, I think I'll try to make one.

[MeisBarry]

I made one designed for the method mh described out of a paperclip (please don't yell at me ). Actually it worked well and I liked the room it left for the pick. I'm going to experiment a little more with them, because I think it has potential to be a serious alternative in some cases.