All Disc Detainer locks alike?

[Benesato]

I've used my judgment and concluded that none of my questions or comments could be construed as advanced; if I am in error, please let me know.

I have previously lived - and will likely return to live - in Thailand, where padlocks are very often a primary means of security. Rather than doorlocks being used almost exclusively as in Western countries, padlocks are often used to secure doorknobs in apartment buildings, security doors, vendor's stalls to lamp-posts, and gates for those wealthy enough to live in a house.

What strikes me as odd is that there are very few pin tumbler locks (and those that exist are often pretty dodgy), and the market is dominated by disc detainer locks. While I imagine the precision required to make disc tumbler locks is less than for pin tumbler locks, I imagine it would have thought it would be a little bit more costly to manufacture them.

So I've got a few questions that hopefully some people can answer.

Q1. Which locks are generally cheaper to manufacture - disc detainers or pin tumblers?

Q2. Assuming I am correct, and disc detainer locks are more expensive (or at least comparably expensive) to manufacture, why are disc detainer padlocks greatly more prevalent in apparently much of S.E. Asia?

Q3. Are all disc detainer locks alike? Obviously the number of discs will vary, but if I use say a 5-disc lock is it going to be only a little less secure than say the 8-disc locks I believe exist in the U.S.A., or are there factors other than the number of discs (no need to be specific) that can significantly affect the security of disc detainer locks?

Q4. A few times I've had problems with putting the wrong key in, which left the disc in the wrong place (since they're not spring-loaded). I found that pushing the right key in and twisting it anti-clockwise would reset the discs and eventually I could get the right key in and I had no problems. I've also found that a couple of times the lock seemed to be jammed shut even with the correct key turned fully clockwise, but it just took a firm yank to re-loosen the shackle.

My father, however, had such a lock jam up and become unuseable. He's pretty cluey, so I can't imagine that he wouldn't be able to get it working unless it was truly jammed shut permanently (but the lock is overseas, so I can't inspect it myself). On the other hand from what I know of the design (just the basics), and what I know of the feel of using the lock, I just can't imagine it would be possible for such locks to become permanently jammed short of somebody doing something screwy with it. Thus, my final question...

Can disc detainer locks become genuinely jammed/inoperable in any way other than being forcibly messed with? If the answer is no then I will continue to trust them; if not I might take over some Aussies locks when/if I return, as the prospect of having my front security door padlock fail and lock me in or out doesn't appeal to me at all!

Thanks,

Benesato.

[LocksmithArmy]

Generally disc detainer locks are advanced, but you are not asking how to open them or even how they work so I personally dont see a problem with it...
a mod may feel different but till then Ill give my 2 cents

I bought a disk detainer off ebay once, It had a key in it... I have yet to get the key out or even budge it one bit.

from this I conclude they can be broken, I have no idea what happened to make this lock stuck like this... but it is deffinatly stuck.

[Benesato]

Addendum.

I realised I might have been a bit presumptuous there with question 2. So here goes:

Q5. What is the ratio of normal* to disc detainer locks commonly available (or at least non-commercially) in your country?

* pin tumblers and warded locks

In Australia I don't think I've seen a single disc detainer lock - they're almost exclusively brass pin tumblers or warded, so I'd say the ratio is about 98:2 (since I'm sure there are some that I've missed).

Benesato.

[Benesato]

Was it jammed in the open or closed position, LocksmithArmy?

If it was jammed in the open position then it might be the right key and it failed, in which case that's a mark against their reliability. But if it's jammed in the closed position I'd guess some bright spark may have tried the wrong key and been too heavy-handed, which I guess is still somewhat of a blemish, but not sufficiently to deter me from trusting them.

Benesato.

[Jaakko]

In Australia I don't think I've seen a single disc detainer lock - they're almost exclusively brass pin tumblers or warded, so I'd say the ratio is about 98:2 (since I'm sure there are some that I've missed).

And in Finland that ratio is the other way around: 98 disc detainers per 2 pin tumblers We mainly have Abloy locks, not those cheap disc detainers that can and will jam for just about anything.

The reason they jam is because of lousy tolerances (the lock barely works with the proper key) and if dirt gets between the parts, it doesn't help it.

The amount od discs or the amount of gates a disc has is in direct connection to the security of the lock. More discs means more to pick and more resistance to forcing/drilling.

Also the keyway shape determines a lot of the safety. If it is symmetrical and in the center of rotation, picking tools are easy to make and use. If the keyway is not symmetrical (like Abloy Classic) and possibly out of the center of rotation (like Abloy Classic), then it is quite hard to make tools and use them. If the keyway shape has wardings or there are wards in the bottom of the lock or in the last discs, it makes it even more difficult to make/use tools.

Also the location of the tensioning disc determines pickability. If it is the first disc, it is easy to tension and there is lots of space for the tool to move in the lock, but if it is in the bottom or in random position, then it becomes quite much harder to make and use tools.

Disc detainer locks in general will get jammed or stop working completely if forced by turning the discs.

The problem of not-aligned discs in the lock while inserting a key is a design flaw. There should be at least one cut that is cut to the deepest position, this prevents the key from being removed before the discs are in the "neutral" position. Other option is to use some sort of locking element (like in Abloy Exec, Protec and Disklock Pro) that locks the key in place if it is turned a bit.

Generally pin tumblers are cheaper to manufacture, because there is less different parts in them and they are technically very simple locks. But there are a few exceptions. A lot of the price also depends where the lock is made and to what quality.

[LocksmithArmy]

In the US I rarely see disc detainers... ever

It was an abloy classic, and jammed closed...

[unlisted]

I am locking this for now, there is already a discussion on disc detainers in the mod forum. Once the administrators made a decision this will be unlocked, or moved to advanced.


Please until such a time, no more discussion on disc detainer locks. Any further discussions before a decision is made will automatically be deleted without notification.