Art Webb wrote on 03/24/15 at 15:45:47:


This isn't going to work on an "L" shaped allen wrench?  It will only help to strip out the hex in the bolt.

It also doesn't work on open end wrenches.....it just rounds the hex off the bolt head.

I don't recommend what I haven't done. And I've done this many times.

That's not to say it can't be done clumsily or ham fisted and a mess made of it, but I've been very successful with this approach.

Gary_in_NJ wrote on 03/24/15 at 17:37:18:

I said near as good, shock works, whether it's applied via a power tool or a hammer and wrench
also note that an impact wrench doesn't work quite the same way and impact driver does

If you are going to be hammering on tools.....this is the most productive tool to own.  I don't know how you ever get the Phillips head screws out of an engine case on a motorcycle without one of these.  Only $ 23 at Sears....and yes Harbor Freight most likely has a cheap version for less.

It works with the screw inserts, or any 3/8" drive socket.  You really need one of these if you are going to work on motorcycles...it was one of the first tools I ever owned, and I am still using the one I bought in 1972.  (Although I have had to buy a few replacement bits over the years).

You just insert the bit of your choice and place it on the fastener, hold onto the tool with your left hand like you are trying to turn the tool in the direction of removal and hold it tightly into the fastener, and then hit the end hard with a hammer.  The tool transforms the impact force into a rotational force.  The tool will work in either direction, and you have to make sure the tool is set for the direction you want it to move by twisting the tool in the direction you want to go.

https://www.youtube.com/watch?v=DUOghfo7VGI

Gary_in_NJ wrote on 03/25/15 at 05:17:26:


Must be technique....it takes a bit of practice.  Watch the video, and notice how his hand is torquing the tool in the direction you want it to turn while you hit it - they work great!

Like Dave said, you really need to torque the impact driver in the direction you want to turn the screw. Just whacking it with the hammer doesn't work so well. Its a brilliant tool once you get the hang of it and pretty much the only thing that will undo those horrible screws they used to use in the 70's and 80's on jap bike crankcases.be surprised if one didn't work on that disc screw. (+ heat!) Good luck.

Pressure, not sufficient to break anything, just get all the slack out and put some load on it. Be aware that striking it,more flex will be the result. Slowly increase the pressure, and, lest any cry HERETIC for striking a tool other a punch or chisel, remember, we own them so that they can serve us to solve problems. I've heated, bent, I've even cut a 1 3/8 Craftsman wrench in half to get into a tight spot on the backhoe. OR I could have spent several hours and injured my shoulders further disassembling to gain access.
If you have a socket and an Allen wrench, cut the Allen wrench and put it in the socket,,

Or, put a socket on an extension, put the Allen wrench in the bolt head, pull hard enough to see a slight flex in the Allen wrench, use anything LIGHT , a hard stick, something that you can spank on it with.
I Prefer not to use a ratchet here, because it won't flex.
You know I am always pointing out that Dave has it right.
Well, I can't on this. I have many times done what I'm saying. I still much appreciate what Dave has done for this place and respect his skills and experience, but here I disagree.

Quick, quick, quick,  imitate an impact. Also, put a pin punch down in the head of the bolt, smack the crap out of it several times.. rattle the threads.
If you have a butane powered soldering tool , take the tip off, heat the bolt till the female threads are hot, stick ice on the bolt head, get busy with the wrench. Even one of those flex tip refillable butane lighters for fireplaces could help you.
I've seen giving a bolt a jolt to tighten it break things loose.
Once it starts to come out, don't get excited and just go to cranking on it. Take care, oil. Turn it right, let the oil cool and lube the bolt, FEEL of it all the way out.

A ratchet, IMO, is not the best answer.