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Extensible sockets for wrench set


Ok, this is something I have to believe somebody else has thought of, but I haven't seen it, so I thought I would ask readers if they have, and if not, to put it forward.

Everybody has a socket wrench set. The wrench heads tend to come with a square hole in the top, typically 1/2" or 3/8" square, into which the square drive from the ratchet inserts. There are sometimes spring-locks to keep it in place.

However, when you have a nut that's going on a long bolt, you can't use a standard socket as the bolt won't fit inside. So you need to get a "deep socket" head, which may be able to handle the long bolt. Yes, you shouldn't have such long bolts, and perhaps should saw off the end, but in reality this happens in places where that's not easy or worthwhile. You can't have just a deep socket set, because that's bigger and heavier to carry around, and may not fit in various confined spaces.

The problem is that the drive is a solid square pin inside the wrench head. If the drive were able to grasp the wrench head from the outside, like a standard nut, then you could have an "extender" which could make any of your sockets a deep socket. To do this, the top of the wrench head would not be round, as it typically is, but hexagonal. In fact, your "extender" could simply be another, larger wrench from the set which fits around this hex head. Or you could have a small number of extenders in various sizes, and in extreme cases, multiple extenders. The extenders might do well to also have spring locks like the current drives do, to hold elements in place for you.

One could also have a thin hex shell embedded in the socket, the way lockable lug-nuts do, but that would not be as strong. Of course, one could try to do a whole new type of driver which is hollow, but the existing drivers are so well standardized now (there are not even metric versions) that I doubt it would get much adoption.

While we're on this topic, here's another idea. Organizing socket wrenches in a case is a pain. They often fall out and it's hard to put them all back in the right place. I've seen colour coded sockets (fairly good) and laser etched numbers that are easier to read, and cases that try to bind the wrenches so they won't fall out as easily. Realizing that the outside does not have to be round, I wonder if we could have patterns at the nut-end of the wrench that make it easy to slot how they go into their case. Perhaps just a couple of bumps or notches, so that no wrench can go in the wrong slot, even a slot for the wrench that is just a bit bigger.


I love how you just assume that everyone of course has a socket wrench set. I like that world view. Wrong, but I like it.

I've seen sets of box spanners that stack as you describe, the limitation being that you can only go either bigger or smaller from the size you start with (depending on which end you're using on the nut/bolt/socket head in question). They're common in older tool kits I suspect because they worked on spark plugs in the days when long sockets were prohibitively expensive.

While originally designed as a line wrench for use with such items as brass fittings on copper tubing, the open sided design would be fine for this use too.

You could get away with just a few Alden wrench sizes, if you find a set of sockets with only a few different hexagonal top sizes (or if you decided to grind your round ones into just a few hex sizes).

But one of the advantages of standardized socket wrenches is you can put them on a variety of handles, including power drivers, which is important if you're going to do a ton of bolts.

I'm not going to rush out and grind my sockets, but I just felt this was obvious enough that somebody would have done it, since for forged tools at least it seems a minor mod to make the round sockets something that can be gripped from the outside one way or another.

Your post is a great argument for including images in your postings. I could sit there and read your post slowly and carefully to parse what you are trying to illustrate in words. But that's too much work. Words are the wrong language for what you're trying to communicate. Please include a sketch of what you mean. Does your blogging tool not support that?

But it was a busy week. Imagine a round socket wrench head with a larger hexagonal nut on top of it with a square drive hole in the nut, through which one can put the drive, or one can have a bolt stick out if you are driving this head with another, larger head.

Interesting. I've found, though, that when the bolt is long enough to need a deep socket head, it's because the socket that the nut is screwed down into is deep. In that case, you need the socket head to be thin enough to fit into the socket and your idea would not work. I'm thinking of engine blocks, for instance. (The other case where the bolt needs to remain long is on parts where the assembly might need to be taken apart and put back together several times--exhaust clamps come to mind--and your idea would be useful here.)

But if these cases are both present for any significant subset of tool users, then having separate wrenches would be redundant because you would need the deep sockets anyway.

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