I need to loosen a 3mm hex bolt in side an appliance. The simple"Allen Hex "L" shaped key does not let me reach and turn the bolt located in a tough position inside the appliance

Have been told to get " a 1/4" drive socket with extension and an allen drive socket"

I need a 3mm "hex bit" as I have always called them.It has to be a "male" shaped bit as the bolt is female. I need a holder for that bit And I need an extension arm

But nothing is called that when I look on line What is a "socket"? Is that another term for the bit? What is socket wrench? Is that another name for the holder Why do I see so many female hex "sockets" and such few male ones?

All help will be appreciated. What do I ask for?


I believe you're looking for an allen head ratchet set, like the one below. A trip to your local hardware or home improvement store might be in order so you can see some products to get a sense of whether or not they can fit in the small space you have before you make a purchase.

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(http://chapmanmfg.com/ , also available on Amazon)

I've never used this particular manufacturer's tools (and this kit might be a little expensive for a one-time job) so I'm not necessarily recommending this particular kit, but the kit includes a low profile ratchet that may work well in a tight space. There are other kits out there that use a similar small ratchet.

enter image description here

Many ratchet sets use a standard 1/4" ratchet with an adapter socket that takes the allen wrench insert, so it ends up being a little bulkier than this ratchet above appears to be. Here's an extreme example, this looks like a 3/8" ratchet with a 1/4" adapter on it, then the 1/4" adapter has a hex bit adapter, then the hex bit is on the end:

enter image description here

Another option - flexible drive for a socket wrench:

If you do get a standard ratchet with a 3mm hex bit, then you might be able to use a flexible drive for your ratchet to get into a tight space -- it can bend around obstacles while still being able to turn a fastener:

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(Image from Amazon)

One more option - a ball-head allen wrench:

Another tool that might be useful would be a ball-end allen wrench:

enter image description here

(image from Amazon)

The ball-end lets you insert it into the bolt at angle instead of having to go straight in. However, the ball-end doesn't fit in the fastener head as securely as a standard squared off wrench, so you may not be able to give it enough torque to break loose a tight fastener. Here's a closeup of the ball-end:

enter image description here


Depends on access. Sometimes you must create access by removing parts. Other times there is a access hole to go through with a bit on a long extension. Or you can use a 1/4" 3mm hex bit with a 1/4" combo wrench to turn it.

Most of the time, if it seems like it is impossible, then typically you would be wise to disassemble further to gain access as most things are not that difficult to take apart. Just take pictures as you go, put screws back in holes they came from, and/or use a pan to keep the parts organized.


This is Joel from Chapman MFG.

Thanks so much for suggesting our set! We're a tiny shop (12 people) in Durham, CT and do not have a large marketing budget, so the majority of our sales comes from recommendations.

If you just need to reach one 3MM screw, we have a metric allen set for $13 http://chapmanmfg.com/products/2

Or you can buy just the CM-13 ratchet and the CMS-43 3MM open stock ($7.05). It won't let me post two links here but everything is available on our website, or you can give Peggy or Rebecca a call at 860-349-9228.

Without looking a picture of the fastener you need to reach, I believe a ball end allen or one of our ratchet & bit set ups is what you're looking for. The benefit of our tools is that they ratchet instead of a ball allen which you need to remove with every turn, but again depending on your situation either might work.

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