"DoN. Nichols" wrote in
:

On 2012-10-10, Doug Miller
wrote:
Jon Elson wrote in
:

Ro Grrr wrote:


I'm getting a DIEBOLD FILE SAFE that is about 5 feet tall and
3 feet wide, double doors. Its locked and there's no
combination so I'm probably giong to have to drill the door
to get into the combination lock.
Do you know if it is a 3-number combination or 5? If 3
numbers, I'd just try them all, it is probably a lot faster
than trying to drill a good safe, even if you knew the exact
spot.

I don't know much at all about safes... but I do know a little
bit about math.

If there are (as has been suggested up-thread) 100 numbers on
the dial, "try them all" is not practical, as there will be
either 100*99*98 = 970200 possible combinations (if a number
cannot be repeated) or 100^3 = 1 million (if it can). Assuming
five seconds per try, with a standard 40-hour work week, the OP
could expect to finish trying them all by the end of June.

Five seconds per try is not practical.

I was just guessing. I believe I said that I don't know much about safes. :-) So I'll take
your word for it.

[...]

My own feeling is that it would be more like a minimum of 30
seconds, and likely 45 per try, which makes the time required
grow rather rapidly. :-)

Let's take the lower number. That means instead of finishing
around the end of June, he'll finish in mid-April -- of 2018.

But even using my guess of 5 seconds, it's hardly practical.

If there are only 45 numbers on the dial instead of 100, he
might finish by the end of this month.

Multiply by at least six for the longer time to work the
combination, so you are up to a half working year with the
smaller number of combinations.

BTW -- the same number can be used for the first and last
entry,
but should not be used for two immediately adjacent entries.
And really, you want something like a separation of two or
three. And the last entry should not be zero, because there is
a permanent zero following that.

Thanks, DoN -- I learned a bit today. I hope the guy that suggested "try them all" did too.