You might already know that Master combination locks of the cheap kind (are there others??) can be shimmed and even opened with a thin lever pushed between the dials.
But what do you do after months of absence when you can't open the lock on your beach shelter or storage place?
The answer is simple: give you lock a nice knock and it will pop open :)
Too easy and too complicated to explain, after all you have to hit a lock with something else...
So check the video and be surprised how easy it is.
And no it does not matter what you use for the hitting, wrench, hammer, steel bar, rock, your head...
Even the angle is not really important...
Here you can see how these lock pop open by y simple bump, or if you drop them on the floor...
In the following video you can see how the entire locking mechanism is bypassed with a thin piece of metal cut from a feeler gauge:
(Sorry, something went wrong with the video and there is no audio but I guess the clicking noise is not too important ;) )
Those locks (and many others) can be "shimmed" as well.
This is a simple technique where some thin metal is inserted around the shackle and pushed down to force the locking pins out of the way.
It only works on locks with locking pins, the ones using steel balls can't be shimmed, so look for those instead ;)
As there is more than enough info on this flaw on the net and Youtube I simply refer you to a Wiki link:
But just to show how badly designed these Master locks are I took the liberty to dismantle one.
No, not the usual way of grinding for hours to get a window in the case, there is a much easier way.
Simply drill out the only pin holding the entire lock together LOL
And it is not even hardened steel which would deflet your drill, even a blunt drill will get it out.
You can see in the vid the mechanics especially the locking bar that is simply hold in place by a single spring and the fact that the case is holding it all together.
Also explains nicely why the bumpning works so well considering the weight of this plate.
This is not intended to be used for illegal activities!
See it as yet another reminder why you should not use Master padlocks for anything of value!
Master also bought American locks and shortly after replaced their standard locking cylinder with a much cheaper version.
The new cylinder has only 5 instead of 6 tumblers, uses very cheap and soft cast iron instead of solid brass and there is no warning label on the thing either.
There are really good locks out there that most hobby pickers like me won't be able to open, the Abloy Protec series is one that offers door and padlocks, and there is the company Bi-Lock that makes locks with two keyways instead of one.
I can't stress it enough that a good lock is often what stands between your security or even life and some low life doing illegal things.