Metallurgy question--defeat hardened padlock shackles?

[devildog]

Been doing some reading about metallurgy since the recent acquisition of my propane torch (hehehe ) and after learning how steel is made to be hard, soft, or anywhere in between and reading this OUTSTANDING post on how to heat treat your picks, which someone really should bump BTW, I got this notion once I learned what 'case hardened' meant and immediately thought of the 'Hardened' stamp you see on padlock shackles:

If you wanted to easily be able to cut through a padlock shackle with some boltcutters or saw through it quickly with a hacksaw, which is precisely what the hardening is meant to prevent, couldn't someone just heat up the shackle with a propane or butane torch, some of which are small enough to carry in the pocket, and then wait 15 or 20 minutes for it to air cool, and then cut right through it with a simple hand tool, such as a file or hacksaw or small pair of bolt cutters, which would then go through it as if it were warm butter?

Now, I don't know how well this technique would fair on the higher-end padlocks with boron or cobalt or whatever other weird super-hard element alloyed into the shackle, such as abus or medecos, but I would imagine that on your average decent-quality padlock such as Master or American it would work quite well, as these have shackles that are just plain steel that's been case-hardened, yes?

A locksmith could do this with something he couldn't pick, such as a particularly nasty American (look, I know that a lot of the guys here that are locksmiths may laugh at that idea, but most locksmiths, from what I understand, aren't particularly talented manual pickers, and many haven't used anything other than a snap-gun or electropick in ages--anyone who IS a locksmith and wishes to correct me, please do so!), or a thief could do it just by heating up the shackle, walking away, and then coming back 15 or 20 minutes later with a small pair of boltcutters under his jacket to just quickly slice right through the shackle.

[raimundo]

I don't think that the little torches would get it hot enough fast enough, but a regular size bernzomatic would do the job easily, it might also set fire to any nearby wood or plastic, and the whole thing would take time, to heat, then to cool enough to touch, quenching may harden the metal. and the springs in the lock would also lose their temper. if your gonna go after anything with a torch, use the oxyacetylene and just do the job right from the beginning, takes less than a minute. the oxyacetylene gets the part being cut very hot very fast, and its not a matter of de tempering then cutting. its just cutting. You should probably look at google for "dave mcomie's penetration party"

[wtf|pickproof?]

I don't think this is ontopic on this site and expect this tread to "vanish" soon.

My knowledge in metalurgy is very limited, but I don't see a reason why this shouldn't work. Maybe the only reason it isn't done, is: boltcutters cut them anyways and it might take some serious time to heat a padlock shackle with a pensized propane torch.

just my 0,02€

[yippeegollies]

I haven't found a shackle type padlock yet that my grinder wouldn't cut through in less than a minute.

Yip

[Chrispy]

Why not just heat the metal and cut it with bolt cutters straight away? The metal will obviously be softer while it's hot and you wouldn't have to wait 15 mins. Or am I way off base?

[devildog]

No, that sounds right Chrispy, I just didn't think about it enough before I posted .

Yip, you're dead on about the angle grinder being the easier way to go here, but I mainly had more nefarious characters in mind because of where I got the idea: I came up with this thinking about a news story I read a few days ago about thieves (article mainly concerned teenage punks trying to break into vending machines) being foiled by the new boron/cobalt/tungsten alloys that are being put into padlock shackles now, and that hardening of the shackles had already forced them to stop using the little 14 inch cutters that they could put under a jacket or shirt and start using the 42 inch ones that weren't quite so easy to conceal .

It just occured to me to mention it because most of us here know not to trust anything to a Master or Brinks padlock because they can be shimmed very easily, picked relatively easily, and now I thought I saw another reason--that it's possible to cut the hardened shackle if you feel like hauling around some 42 inch bolt cutters, OR something to heat the shackle with to anneal it (correct me if that's not the right term--I just started my 'wikipedia education' today, mainly metallurgy stuff ) and then take a smaller and more concealable hand tool to it. Anyone know if American is just using the regular case hardened shackle like Master is, or if they're doing something different (American seems to be a bit more on the ball, much more pick-resistant plus the unshimable ball-bearing thing and all, than the previous two that I mentioned)?

[Chrispy]

I have a portable butane gas torch (about 35 cm high) that could easily fit in a bag or under a jacket, along with some bolt cutters about the same size. It would be stupidly simple to head around to places you wanted to knock off and get into them by way of the above mentioned technique.

Anyway, this thread is heading in the direction of 'lockedtown', so I might just end it there, mmm?

[Mad Mick]

... if your gonna go after anything with a torch, use the oxyacetylene and just do the job right from the beginning, takes less than a minute. the oxyacetylene gets the part being cut very hot very fast, and its not a matter of de tempering then cutting. its just cutting. You should probably look at google for "dave mcomie's penetration party"

A portable ox/acet kit with a welding tip can cut quite easily. Get the material glowing orange, then open up the oxy valve to make the cut. Not quite the same as having a dedicated cutting torch, but lock hasps ain't that thick either.

Given the choice though, I'd go with Yip & use an angle grinder...with something protecting the door/frame/toolbox/locker etc. from the sparks. Probably a lot quicker than applying the heat & then cutting.

[Minion]

But noisier, no?

[mckutzy]

propane torch nomatter what size wont touch boron, cobalt, vandium, cromium, all bolt shackle materials. the shackles that are cheaper, that are case-hard are still tool steel. ur going to have a hard time heating the shackle to releve any temper as well leave it maluable enough to cut through unless they are less than 1/4" dia. i was talking to a couple of firefighters about locks they have come across and one time, was a gate with an abus padlock(3/8" dia shackle) they couldnt cut it cold with a 4' bolt cutters. so as for boron alloy i doubt it.

[n2oah]

i was talking to a couple of firefighters about locks they have come across and one time, was a gate with an abus padlock(3/8" dia shackle) they couldnt cut it cold with a 4' bolt cutters. so as for boron alloy i doubt it.

They still use manual bolt cutters? I was at a volunteer fd with my friend (his dad is a volunteer) and he was showing us around a bit, and we came across these hydraulic bolt cutters. His dad told us that they could easily cut anything they came across. We also played with the thermal cameras-- those things are awesome.
As far as cut resistance goes, I was thinking of doing tests with padlock shackles and all kinds of attacks. I have about 5 different shackles from American, Master, Abus, and some generic brands. I would test each schackle against cutting, freezing, and various other forms. I never got around to testing, though.

[Chucklz]

Just so that everyone knows, American is now owned by Master, so who knows if the shackles will be interchanged or what.

[n2oah]

Just so that everyone knows, American is now owned by Master, so who knows if the shackles will be interchanged or what.

I thought that too place a long time ago, but I wasn't sure.

[n2oah]

Just so that everyone knows, American is now owned by Master, so who knows if the shackles will be interchanged or what.

I thought that took place a long time ago, but I wasn't sure.

[devildog]

Actually, I was sifting through some stuff over at totse (there's some interesting things over there, but you have to dig through the rest of the crap first) and something mentioned in a post/file/whatever about bypassing padlocks was that even with cobalt and whatever else they're putting in the shackles, hydraulic bolt cutters would probably go right through it, and they had a link to http://shop.store.yahoo.com/landfallnav/-snrc2.html, of course the only problem is I doubt the script-kiddie who wrote it or your average thug trying to break into a vending machine can afford to pay a grand for some bolt cutters