# Help me break in (not illegal)
**URL:** https://boards.straightdope.com/t/help-me-break-in-not-illegal/604343
**Category:** Factual Questions
**Created:** [November 28, 2011, 3:03pm UTC](https://boards.straightdope.com/t/help-me-break-in-not-illegal/604343 "2011-11-28T15:03:44Z")
**Posts on this page:** 12
**Page:** 1
### Author:  [@Hershele\_Ostropoler](https://boards.straightdope.com/u/Hershele_Ostropoler)
#### Post date: [November 28, 2011, 3:03pm UTC](https://boards.straightdope.com/t/help-me-break-in-not-illegal/604343/1 "2011-11-28T15:03:44Z")
My girlfriend cleaned the bedroom this weekend and found two combination locks to which the combinations are long forgotten. Since I don’t like throwing anything out, and one is locked around the handles of a tote bag, I’m trying to find a way to figure out the combinations.
One of them, the one on the bag, is at least eight years old, from Master. I actually set the combination on this one, but I don’t remember what it is. It’s a four-digit combination, the lock consists of four rotating things. I’m trying the brute-force approach and so far I know 7777 through 7966 are wrong.
The other one isn’t locked. It’s a standard dial lock with no indication of the manufacturer or any identifying information. I’m unwilling to try brute force on that one, since there are between 59,280 and 64,000 combinations, and trying one is a more involved process.
I’m willing to post a link to a picture of the locks and today’s paper to provide evidence that I have these locks in my possession. I’ll set them to the numbers requested by the first response(s) to respectively provide a number between 0000 and 9999 and between 0 and 39.
If anyone can help me, it’s someone at SDMB.
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### Author:  [@randomface](https://boards.straightdope.com/u/randomface)
#### Post date: [November 28, 2011, 3:47pm UTC](https://boards.straightdope.com/t/help-me-break-in-not-illegal/604343/2 "2011-11-28T15:47:23Z")
I think this link might help you, at least for Master-Locks. [How to Crack a "Master Lock" Combination Lock: 2 Ways](http://www.wikihow.com/Crack-a-%22Master-Lock%22-Combination-Lock) It will narrow the possible combinations down to less than 100 for spinning dial locks.
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### Author:  [@Scuba\_Ben](https://boards.straightdope.com/u/Scuba_Ben)
#### Post date: [November 28, 2011, 5:58pm UTC](https://boards.straightdope.com/t/help-me-break-in-not-illegal/604343/3 "2011-11-28T17:58:37Z")
If I understand you correctly, the first lock consists of four dials, each with a digit 0 to 9.
I can brute-force a 3 dial lock of this type in about 15 minutes, depending on how bored I get. A 4 dial lock would take 2 to 3 hours. I don’t know of any shortcuts, sorry.
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### Author:  [@RearEchelon](https://boards.straightdope.com/u/RearEchelon)
#### Post date: [November 28, 2011, 6:43pm UTC](https://boards.straightdope.com/t/help-me-break-in-not-illegal/604343/4 "2011-11-28T18:43:23Z")
Depending on the model of the first lock (the 4-dial), you can sometimes feel out the combination by pulling on the shackle while turning the dials. If it is a type of lock that can be opened this way, you will be able to feel a difference when it clicks into place on the right number. Many locks will simply refuse to turn when pressure is put on the shackle, however.
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### Author:  [@FlyByNight512](https://boards.straightdope.com/u/FlyByNight512)
#### Post date: [November 28, 2011, 6:52pm UTC](https://boards.straightdope.com/t/help-me-break-in-not-illegal/604343/5 "2011-11-28T18:52:40Z")
Try 1492, it’s the usual default for resettable four dial locks. If you look up the brand there may be directions online for setting it that can help.
(I trust that you’ve got them legally, but if you’re going to post a photo I propose 9347 for the four dial lock and 8 for the combination.)
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### Author:  [@Hampshire](https://boards.straightdope.com/u/Hampshire)
#### Post date: [November 28, 2011, 8:41pm UTC](https://boards.straightdope.com/t/help-me-break-in-not-illegal/604343/6 "2011-11-28T20:41:16Z")
For the dial type check youtube. Theres a few videos of how to make a shim out of aluminum from a can that you can pop the lock open with.
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### Author:  [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)
#### Post date: [November 30, 2011, 3:27am UTC](https://boards.straightdope.com/t/help-me-break-in-not-illegal/604343/7 "2011-11-30T03:27:49Z")
I remember (from reading Dr. Richard Feynman’s autobiography) that the dials look more accurate than the locks actually are. I think that only about every 5th number was significant. Thus 3, 4, 5, 6, 7 were all the same for combinations. So he just used 0, 5, 10, 15,… as possible numbers for combinations. That really reduces the trials needed in the brute force method.
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### Author:  [@Reply](https://boards.straightdope.com/u/Reply)
#### Post date: [November 30, 2011, 3:36am UTC](https://boards.straightdope.com/t/help-me-break-in-not-illegal/604343/8 "2011-11-30T03:36:08Z")
Why even bother trying to figure out the combinations? Just get a bolt cutter or borrow a power tool and cut through them.
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### Author:  [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)
#### Post date: [November 30, 2011, 4:02am UTC](https://boards.straightdope.com/t/help-me-break-in-not-illegal/604343/9 "2011-11-30T04:02:05Z")
> [@Reply](#):
>
> Why even bother trying to figure out the combinations? Just get a bolt cutter or borrow a power tool and cut through them.
And waste a perfectly good lock?
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### Author:  [@Reply](https://boards.straightdope.com/u/Reply)
#### Post date: [November 30, 2011, 4:34am UTC](https://boards.straightdope.com/t/help-me-break-in-not-illegal/604343/10 "2011-11-30T04:34:40Z")
> [@t-bonham@scc.net](#):
>
> And waste a perfectly good lock?
Is your time really worth the hours it takes to brute-force a $10 lock?
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### Author:  [@Senegoid](https://boards.straightdope.com/u/Senegoid)
#### Post date: [November 30, 2011, 10:55am UTC](https://boards.straightdope.com/t/help-me-break-in-not-illegal/604343/11 "2011-11-30T10:55:43Z")
> [@Reply](#):
>
> Is your time really worth the hours it takes to brute-force a $10 lock?
This. If you spent the same length of time doing some money-gaining activity, you could more than pay for new locks. Even if you stood at a freeway offramp and begged for spare change, this is likely to be true. If you spent the same time inventing a new social-networking web business model, you could buy a whole bunch of new locks.
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### Author:  [@SmellMyWort](https://boards.straightdope.com/u/SmellMyWort)
#### Post date: [November 30, 2011, 3:45pm UTC](https://boards.straightdope.com/t/help-me-break-in-not-illegal/604343/12 "2011-11-30T15:45:36Z")
Maybe the OP sees it at a personal challenge. There’s nothing wrong with that.