Is there a way to rekey a master lock to accept a blank uncut key?

I need to secure an ammo can that has a hasp and a Master Lock. The first time I replaced the lock because of lost keys, I had an additional key made the second time and I ended up letting someone who lost their key take it to get another duplicate made and he lost it too. What I want is the ability to just tell someone who has lost the key to go buy a blank and therefore won't have to give up my own key. That is the purpose of my question.

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iceng6 years ago
You can re-key it to accept his key and the blank at the same time.
That's Cool don't you think ?

lemonie iceng6 years ago

How do you do that then?

iceng lemonie6 years ago
A picture of single pin two key tumbler lock and
a real 5 pin one key tumbler lock........ A
lemonie iceng6 years ago

I know how these locks work, and having taken them apart I know what fiddly-sods they are to reassemble.

The right tools help. So does a bit of practice, and knowing a few tricks of the trade.

But it's _still_ the wrong answer to the querant's stated problem.
Just like any other master keying. The bottom pins are replaced with appropriately split pins, so the two keys each create their own shear lines to permit the plug to rotate.

As I mentioned in my other post, that does have side effects. Sloppy master keying of this sort loses more security than proper master keying would. Knowing how to manage those trade-offs is part of what makes locksmithing an engineering field, or even a craft in the medieval sense, rather than just another job -- having the tools and parts is only the start; knowing what to do with them is what you're really paying for.
I get that, but it sounds like more hassle than getting a few copies made?

Absolutely. Master keying, especially to that key, is the Wrong Solution for this user.

"The customer is not always right. The customer is always the one with the money. Sometimes it's better to be right than to take the money." I'd pass on this job; it frankly feels more like someone is trying to make an excuse for buying uncut blanks than anything else.
orksecurity6 years ago
Alternatively, you could always remove _all_ the pins, so any key (or screwdriver, or sneeze) could open it...
Vyger6 years ago
Another even simpler solution would be to get a combination lock. Just make sure to write the combination down somewhere.
orksecurity6 years ago
Well, the size of blank uncut keys is a bit variable, but ignoring that complication -- yes, you could do it.

Of course you'd destroy your security by doing so. Straight-line keys are never a good idea, and this one in particular is begging to be picked. Also, master keying has been called "controlled destruction of security" for good reason -- adding that uncut key to a lock that responds to a normal key is going to actually create a whole bunch of other security holes.

It's really easier and cheaper and more effective to just make a bunch of duplicate keys. Not least because it's often harder than you might expect to get a store to sell you an uncut key blank.

Possible? Yes. Wise? No.
Also: It depends on what you mean by "a Master Lock". The cheap padlocks are not rekeyable. Master *does* make rekeyable padlocks, along with many other kinds of locks, but they cost more than the simpler prekeyed locks.

Also remember that there are a number of different levels of both physical strength and security in the Master padlock line (as is true for other manufacturers, of course). If you buy the cheapest possible, don't expect it to perform up to the standards of the more expensive ones. Of course for many applications, where you aren't looking for serious security but just tamper prevention, that cheap-and-cheerful model is all you need.
You'll have to see how accurately the blanks are made, as if the tolerances are quite large, it is possible that some blanks may not work.

Also, it is unlikely that a locksmith will be able to make any alterations to a padlock, at least not without a lot of time and effort.

Have you considered using a simple combination lock, and setting it to a simple combo like 2345.
lemonie6 years ago

I thought that the purpose of keys was to effect some kind of security.
Why not just leave the thing unlocked?