Open a Master Lock Without the Combination in 5 to 7 Attempts 

2:08 decode a Master lock 9:26 find the 1st number 10:14 find the last number 11:44 find the 2nd number 14:53 decode a 10 push buttons lock 16:03 decode a cheap bicycle lock 17:34 start decoding the cheap bicycle lock 19:20 decode a luggage lock 22:40 open core of the luggage lock

Finally! A tutorial on how to do this that isn't just 'I already know the combination, so all I need to do is adjust pressure to make it look right on camera' kind of video. You go into the why and explain well. For reference though, I am a math major so I can see others struggling with the modulo arithmetic, but w/ this I was able to find my old combination so, cheers mate!

I honestly ran around my house screaming when my lock opened up! Thank you this was so awesome to try and figure out

Nice, thorough explanation. I still can't open mine but your video gives me hope.

Thanx i saved all my locks i firgit the combos for . Now ill have my locks back

I jumpscared myself when mine opened. 😂 I've been trying for three days. I really needed to see what was going on inside - not an animation. Thanks for prying that thing open. I want another lock to crack now lol.

I had a bike lock just like that when I was a kid. I thought I was clever when I removed the keeper spring and jumbled the rings to change the combination. My dad gave it a good pull and popped the keeper spring out and the lock opened. So the combination was "give good pull". This made me very curious about locks and I am still taking them apart to see how they work. Made me a better programmer.

Thank you. I'm waiting on the combo from Master lock, but this worked to solve the lock combo without having to wait. The combo works, so I will get to double check my work once Master lock gets around to replying to my email. Thanks Ted Shaffrey.

Great explanation. I was shocked when I finally got it open, as I didn't expect it to work. 😄

I’ve been trying to unlock my old gym lock for 2 hours now

I have master lock...and been trying for 7days already....tq...nxt video plss...

Thank you, worked perfectly - of course on the last possible option!

I just unlocked my lock . Thank you so much for the video.

I wanted to thank you for your video. My lock was really rough and I couldn't decipher Number 1 but could make out number 3 clearly. So I used your rules to create a spreadsheet of possible Number 1 and 2s based on the rules you presented which resulted in 56 possible combinations. It was the 44th one in my list that opened it. I'm stubborn enough to see if I could only open one only feeling the 3rd number and I guess you can. Thanks

Excelente explicación, muchos saludos desde saltillo coahuila MÉXICO.

This video finally made me remember my code combination.

THANK YOU for explaining in detail why things work the way they do. Every other video did not help me and seemed to be happenstance that they could unlock it. This made a lot more sense to me and with it I was able to get my childhood lock back open.

while listening to this scholarly dissertation on modulo 4 math applied to master lock combinations - i forgot the full sequence for my own master combination lock ! fortunately i was able to reconstruct the full combination with modulo 4 math calculations. (i hope !)

i could only find the first one but did a quick bit of calculating and a good soul read of my lock and figured it out!

We are trying to open a lock and it has been helpful.

I was waiting for your Leatherman to break prying like that. Glad it didn't.

Weird thing: my Dudley combination lock (by Master Lock BTW) has only 1#, not the usual 3#'s, to open it. Turning it to #10 always opens it. The combination card supplied with it only showed#10 as the 1st # to dial, with the 2nd and 3rd spots left blank on the card. Anyone heard of that?

that little nub by the yellow tumbler does in fact serve a purpose. Watch the tumblers when you close the shackle!

A lock only keeps an honest person out. I’ve got bolt cutters that’ll open almost any padlock in 10 seconds. That takes all the skill and fun out of it though. Thanks for making a video that explains how the mechanisms work. There’s too many videos out here that expect one to understand what they should be feeling, looking for, or hearing without any real visual. The cut outs are definitely a plus.

What's the physical lesson or manufacturing feature that parallels the mod math's possible solution suggestions?

This video is giving me hope to open my lock bc i need my books for class cause i forgot the order of my lock

Except for one major issue...the new Master locks with colored bodies or dials don't work using this format...that's because there are multiple "sticky" points when revolving the dial. Maybe i'm not doing it correctly, but i've tried every instruction video here and none work with the newer model locks. If anyone can comment or help, i'm more than happy to learn how to decode these type locks. Thanks anyway.

You've got it all wrong, officer - I'm an engineering student studying for an exam...

For the Master lock at 13:41 you mention the second digit will never be 2 before or 2 after the last digit. I finally got one I have from high-school unlocked and the last 2 digits were "2" and "4" so I'm not sure that is accurate. Everything else was super helpful though and I easily found the first and last numbers. I just had to use trial and error for the middle number when the 7-ish options I had didn't work.

Question, you said to find the second number for the combination it must be minus 2 of whichever mod 4 you get… what if it’s 1 mod 4 , or does that never happen?

Can the remainder be 0?

Thank you so much! no more jail for me :D

Bike lock is pi rounded 3.146 (3.14159... )

So on my combination lock, the combo's 2nd number is 10 before the first number (which you stated it never would be). And explanation for this? I'm curious. Great video by the way.

I am still struggling 😅

I just opened one of those locks a couple days ago and those 2 dials are plastic looked a little different inside uhmmm

Somebody stayed up late figuring out how to make the first combination lock. Now you need a PHD in mechanical engineering to open one.

what happened to the suit ?

I need a written explanation of getting the second digit haha toooo confusing there

What if the First and Last number don’t have the same remainder????

i opened two and more this padlock .. they all have different knots with different distance on the two wheels... not like this video talking about. all the two wheels have exactly measurements. you only find is the last # on the spinning wheel, the open gap is bigger than the the gaps ..

Hey Ted Shaffrey Look at what your “friend” Lincoln posted on RU-vid

The "not -2, not -6, not -10" rule for the second number is not correct. I have a lock with N2 = N1 - 10 mod 40. Also, for the last number, it doesn't hurt if you try multiple combinations. So, the algorithm is: - Find the first number D with the described method. - Try as first number A in (D, D-1, D+1) - For the second number try B in (A+2 mod 40, A+6 mod 40, ... A+38 mod 40) - For the third number try C in (B - 2 mod 40, B-6 mod 40, B-10 mod 40, ... B - 38 mod 40). For the third number don't re-set A and B. Just set another C and try to pull. This requires at most 3*10*10=300 pull attempts and at most 3*10=30 setups for the first+second numbers. As for the first number, let's assume the number is 7. When try to rotate the dial counter-clockwise slowly increasing the pull force. At some pulling force, you'll feel resistance exactly at number 7 and only at that number. If the rotation torque is low when the dial will just stuck no able to move to 6, unless you increase the torque. However, if you increase the pull force, then the dial will stuck earlier, at number 8.

LOCKS ARE TO KEEP THE HONEST PPL HONEST!!!

Two hours? Just as long as this video… fell asleep and when I woke up, it still wasn’t over… yawn

Huh

O

Chapters.. you need chapters so we can skip to the l9ck we are trying to see

Wake me up when he's done.

This guy shouldn't be explaining anything lol

No good 😢

Justin Cappos made a porno when he was 19. It was surprisingly good. At least of those statements is not true.

God my five year old Nephew can open this type of lock,

Aj ah uum ah ah ium ; not a guy that can formulate his narrative in real time. Comes across as premature dementia... tip: script what you want to say.

An Engineering Professor who didn't bother to learn lock terminology. How disappointing. But he's basically right. Lock Hobbyists use these ideas and others to pick locks. It's all about knowing how they are constructed. Keep it legal!

A horrible verbal instruction!

you talk too much !! Bye Bye

Boring

Sorry buddy, I fell asleep 😴 when you had the back of the lock open talking about the red and yellow gear, you need to be much more concise and your voice makes me want to close my eyes, wondering if you were a history teacher or other boring subject as a teacher.😴😴😴😴😴😴😴😴😴😴😴😴😴😴