Tension Wrenches a La Wiper Blade Inserts.





Introduction: Tension Wrenches a La Wiper Blade Inserts.

This instructable will walk you through the quick and easy method for making tension wrenches from the metal inserts found in almost all windshield wiper blades.
A tension wrench is a tool used when picking a lock. If you're unfamiliar with its use, it's probably best to look elsewhere. This instructable will not show you how it's done - just how to make the tool.
Also, there is a video demonstrating this procedure in about 30 seconds at the end. If the steps aren't clear enough, that's most unfortunate, cause the video's not gonna clear it up at all (it's a whole heck of a lot darker than it was when I shot it). The download version should be a LOT better than the imbedded version.


Step 1: Pick an Insert

I have a small collection of these things, so I have the luxury to choose the height, width, and length of my tools. I use some smaller ones for smaller locks and larger ones for larger locks, as logic would have it. Most inserts fall right in the middle and can be used for either end.

Step 2: Size It Up.

Measure it if you want. I have no idea what the measurement would be. It really depends on how you like your wrenches. I tend to prefer mine on the long side as it gives me more spring. Some are shorter, to fit in tight spaces. So, it depends on the purpose of this particular wrench. Once you have a rough estimate, use the pliers to bend the insert back and forth.It should break right off.

Step 3: The Bend.

It may be surprising, but I don't measure this either. Basically,measure how much of the tool you want to be inside the lock, and insert the insert that far into the pliers and give it a 90-degree bend. I recommend making this almost exactly the same measurement as a commercially-made tension wrench if you've got one to compare it to. Otherwise, I'll give you the measurement of approximately 5/8 of an inch (I suppose I can figure out a measuring tape for that much). That size should do for most locks.
You can actually stop here, and that's how a lot of commercial wrenches are, but I like to keep going. It just depends on how you like the feel. Personally, I like to push against the flat side when I'm picking. It feels better,plus adds a bit of "spring." You'll have to try it both ways to decide.

Step 4: One Quick Twist....and It's All Over!

Using two pairs of pliers, vice grips, very very strong fingers, or whatever, give it a twist on the long side. It really is simple. Place one pair of pliers at the 90-degree bend and the other a little ways below that. An inch should be about right. Then, once you have it firmly gripped, just twist in opposite directions. You'll probably have to twist a little further than it seems you should, as the metal has a tendency to spring back a bit.
Congrats - you have a tension wrench. If you want, you can file (or Dremel) the ends to soften them up. I do recommend this, as you'll definitely cut yourself up using it otherwise.





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dats a lot. im in NZ any hints where I culd find windshield wipers ? Nice wrenches, but you need a pick to open a lock.

LOLOL, on a windshield.. Super cheap Auto

Just grab them out of the trash at any shop where they sell/change wiper blades.

That's exactly what I did, sometimes I didn't even go in. I felt a little weird, some weird guy pilfering window wipers out of the trash.

I made mine flat, however a couple days later I made another set with twists in them. So i have a short and a medium one, with and without twists.

Thanks for this instrucable.. My brother lost the only gas cap key I had (he was the lest to have it). I could not for the life of me find anything I could use to make a set of tools from, then I came here :-D

Got a few backup wipers, lots of metal inserts. 20 minutes with my dremel and cutting disk and I had a set of tools.

Got my gas cap off first try (well, second technically since I had to grind some thickness off...)

Been lucky enough to be able to buy any lockpicks n' tools that I wanted for a few years, and in a store where you can really see what yer getting. But, since I ran across Wiper blade steel inserts, I have no use anymore for the Store-Bot stuff that they pass off as 'the Real deal'. I've found different sizes and thicknesses of wiper blade steel, you can make 'em Any size or twist you want, so I never pick up the 'Pro' ones anymore. One problem. I might be bending 'em too fast or something...but, if I don't use just a little Heat from a small lighter? I always find small cracks around the bend spots, expecially underneath the bend. Just read the best stuff on Tempering Metal, in this section, that I've seen in the instructable called 'Yet another Lockpick making...........' ? Trying to say that I think that any metal needs to be heat treated before it will take this much bending (and Last for a while)? Either that, or I need a course in 'How to do it real.....slowly?' (bin told that)

I've been bending the insert for 20 minutes now, and it still hasn't snapped...

Honestly,I don't even use the pliers for this step much of the time. It's pretty simple, just bend as far as you can one way, then all the way back the other way. It usually doesn't take much more than one or two bends, back and forth. If yours isn't snapping, you really ought to call the UFO Hunters because you have some rare, unbreakable metal in your possession.