Tension Wrenches a La Wiper Blade Inserts.





Introduction: Tension Wrenches a La Wiper Blade Inserts.

About: I pick locks for a living. Never pick a lock you don't have a right to.

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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23 Discussions

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.

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...

1 reply

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.

just a follow up- i made two of these today boris and there EXCELLENT. ive had these two 6 pin cylinders that have had me beat for months until now! it looks like the wrenches ive been making were putting too much/not enough tension on the plug but these little babys work a treat THANKS! ps/you dont happen to know of an instructable to make a plug spinner do you boris?

Now that you mention it, no. I don't know of any instructables for a plug spinner. I have seen some homebrew devices somewhere else though. One popular choice is the spring from a mousetrap. You put it around basically a tension wrench. Without the instructions, it may be hard to envision, but it does indeed work. Problem I have with homebrew spinners is that they tend to be knuckle-busters. Not a real problem if you're quick every time. ;) I usually flick my backward-picked locks, and I know one guy who snaps them. What you do there is turn in almost back to the locked position (as close as you cn get without relocking it). Then, just keep tension in the direction you need to turn, and flick it/snap it as hard and fast as you can. I you do it right, and if the lock is loose or lubed well-enough, it should spin just as if you had a spinner. Hrm, maybe I need to make an instructable on that.

I'm goint to try this when i find a wiper blade,I'v had good luck using those long & flat bobby pins you got to heat them up or the will snap some times when you are bending them

nice instructible. been making these forever. street sweeper bristles are not as flexible and tend to snap when you try to bend it. the trick is to go slow. but the wiper inserts are my favorite.

2 replies

I'm not shure on this but culden't you heat the section that you want to bend whit a map gas torch (or another type of gass depending on prefence/availabiliy) I'v never used street sweeper bristles so i was just guessing thats all.

i saw this and said to myself i posted somthing just like this a year ago but then took it off so wow i wasnt the only one with ideas like this i think ill repost that now.................

2 replies

Cool. I mean, not to dissuade you, but if it's the same exact thing, it's a bit redundant. I'm all about seeing different ways to do things. This way works great for me. Can't wait to see what you've got!

yeah when one figures out a way to cheaply produce tension wrenches then you have the upper hand i have friends who payed over 20$ for a tension wrench so i decided it wasnt worth 20$ and started to plan then one day my dad was changing windsheild wipers on the cars and i came across the metal strips... and you know the rest . so i had free tension wrenches and my friends were 20$ in the hole looking very stupid trying to pick locks.