TOK (Top of Keyway) Tension Wrenches -- How and Why?

[Bad_Jason]

Hi,

When is it best to use the top of keyway tension wrench technique. I've read around, watched videos and this technique seems to work well on higher security padlocks such as Federal and American with spools, mushrooms, etc.

Excuse my ignorance, but why is this a better technique and should I implore it every time I encounter a lock with security pins? Is it also helpful when picking a six pin - pin and tumbler lock with no security pins?

Also, would anyone be kind enough to share home brew TOK tension wrench designs and what materials one should use to craft one? Most of my homemade wrenches are made from the strip of steel commonly found inside window shield blades.

I looked around the site before posting this and didn't see the exact info I was looking for in other threads. Please excuse me if this has been covered already.

Thanks,
~J

[Bad_Jason]

Also, what is the best type of file (and grade) to buy for filing wrenches and picks. I plan on hitting up the hardware store after work.

[Squelchtone]

Hi and thanks for your question.

Top of keyway tensioning has 2 main benefits.

The obvious one is that by tensioning in the top of the keyway (or bottom of you're from Europe) gives you more room to go under the pins without disturbing for instance a long key pin.

The second reason has more to do with physics and mechanics of how motion is transferred to other objects. Have you ever been to a car show where hot rods and classic cars are on display with their hoods open to display the engines? If you were to start one of those engines and pull on the carburetor linkage to give the engine some gas the rotational forces of everything moving in a circle inside the engine puts torque on the engine and makes it twist (like the plug inside a lock cylinder) Most engines are not balanced properly in the engine bay and what you'll see when revving the engine is that one side of the car gets torqued more and pressed down towards the ground. When you let go of the gas, the shocks push the car back to its normal position and it sits perfectly parallel to the ground.

Going back to how locks work, especially well made locks, like a lot of the precision made high security locks, you have a cylindrical plug which turns inside a shell, and its central axis is the center of its radius. Because the lock is so well made, if you use a bottom of keyway tension/torque wrench and apply force while picking, the pins closest or furthers away from you will bind more against the sidewalls of the chambers than other pins will, because just like the car being pressed towards the ground unevenely when the engine is revved, the plug is not being rotated evenly, on a very small level one end of the plug is being pulled down lower than the other end. By inserting the wrench to the 'top of the keyway' you are applying the rotational force more evenly across the central axis of the plug, and thus binding the pins with equal force from front to back. It's by no means perfect, but seems to work very very well on locks that are machined to higher standards.

Making a top of keyway tension/torque wrench (turning tool as some call it) is very easy. Just take a 6 inch long piece of windshield wiper insert, take some pliers and bend a 1/8" to 1/4" inch bend on one end. Basically the point is to use the area of the plug just before the 1st pin as a place to rest your wrench. If you make it too long, it will interfere with the free travel of the 1st pin in the lock. Experiment and find a good length that works with the brands and models of locks you enjoy picking.

I hope this analogy was understandable, and you found it useful.

Squelchtone

ps. I will let someone else chime in about types of files and sand paper for making and finishing picks and wrenches.

[Brother Paul]

Hi and thanks for your question.

ETC ETC.

what a excellent answer i learned a lot from this ,,thx

[Bad_Jason]

Wow, thanks Squelchtone, your analogy and further explanation is excellent. I can't tell you how many videos I've watched and literature I've read on TOK with no explanation on the theory behind it. Very helpful stuff!

[loki-aka]

For FINISHING cuts on tools, use a flat and round files, fine cut. The round files work well for radiusing
hooks and rakes. Files come in a variety of qualities, from very poorly made imports to some very nicely made Swiss products. If your planning on making any substantial quantity of tools, invest in the better quality files. A well made
tool will give you a smoother, more consistent cut.

You proably know this, but I'll mention it for the benefit of others. When you file, use the full length of file. Don't
just confine your strokes to an inch or two of the file's teeth- otherwise you'll create an uneven divot on the tool.
Besides, you spent good money for a whole file, why just use an inch of it ?

Please, use safety glasses when metal working. Not worth putting your eye out, even over the most beautiful pick.

[Bad_Jason]

Toki, thanks for the file advice. Very useful.

And I just wanted to thank Squelchtone again for the TOK explanation. I made a tension wrench that fits the top of the keyway of an American lock that had been kicking my butt, and viola, opened in under 3 or 4 minutes. that felt good.

[raimundo]

everything squelchy said and there is the problem of binding at the bottom of the keyway where the tensor blade touchs the cylinder wall this can prevent picking success.
femurat has a post showing how to make a top of the keyway tensor out of a bicycle spoke.
its worth looking for.

[lock2006]

I been picking lock using this method top of keyway on padlocks like
brinks,american padlock and best lock and works pretty well
thank you squelchtone for your very well explain and understandable subject
on TOP OF KEYWAY
thanks.

[Eyes_Only]

I've been using TOK wrenches from Peterson for about 4 years now and they work great. Leaves the keyway mostly unobstructed to move your pick more freely. But when it comes to raking or ripping type techniques the pick can often knock the wrench out of the plug so thats the one disadvantage I see with TOK.

[Schuyler]

Considering how common this question is, and Squelch's phenomenal answer, not to mention Loki & Rai's additional comments, may I recommend this thread for a sticky?

[femurat]

everything squelchy said and there is the problem of binding at the bottom of the keyway where the tensor blade touchs the cylinder wall this can prevent picking success.
femurat has a post showing how to make a top of the keyway tensor out of a bicycle spoke.
its worth looking for.

Thanks for the good words Ray. Here is the link.

Cheers

[Bad_Jason]

Thanks again to everyone who commented on this topic. Very helpful stuff!

~J

[JK_the_CJer]

Also, lots of high security locks have elements in the bottom of the keyway. Using "normal" tensioners usually completely blocks access to these bits. As a result, you're pretty much forced to use top tension. I pretty much use only top tension out of habit on everything now because of this. I feels more reliable...likely for the fascinating reason Squelchtone wrote about. Top tension seems to be pretty common among folks that have been picking for a few years and these are likely the reasons for that.

Some examples: http://theamazingking.com/images/locks/spp-flat.jpg

[rontgens]

I recently got a Peterson prybar and I really like it, being a rookie I'd get frustrated with my homemade wiper blade tension wrenches slipping out thinking it'd popped the lock open only to find the wrench had slipped out.
I also had that annoyance of as said before, the tension wrench binding on the side of the cylinder wall.
The prybar in comparison feels slightly different for me to use but is rock solid.