lock design question

[E-Mind]

how about a large tubular lock that is designed similar to a mul-t-lock - where instead of pushing pins in like a regular tubular lock - you need to push pins to the sides (with pin-inside pin configuration) - meaning you have groves on the side of the tubular key.

does something like that exist? I would think that would make some pretty good high security lock if the keyhole is small enoguh... you would have to pick many pins in a 3d configuration and have the advantage of pins relocking as you turn the key so you would have to repeat the process as in a regular tunular lock...

I am not sure I am visualizing it good myself, and I'm pretty new at this lockpinging thing so I am not sure if I'm missing any obvious problems here...

[Mad Mick]

Kaba?

[digital_blue]

Well, tubular tho. And with telescopic pins... so... um... no. I don't think he means like a kaba.

db

[master in training]

sounds similar to a bramah if im remembering it right, look on crypto, i know theres some great pics of a bramah on there! your idea just sounds like one step more in security with the pin-in-pin system as well.

sounds good though!

[Shrub]

You can get tubular locks which are pin in pin,

The idea you suggest would require a key to push on its side, unless you have an angled edge so the thickness of the key (cut at differant heights around its circumfrance) would move the pins in and out, the thickness required to do this would make it a big keyway as you can not have a radiused cut like a tubular key as when the key was inserted you would meet the shearline but as soon as you attempt to tun it the pins will be trying to go to a slightly differant height as they are rolled around the bottom of the radius, the fact you are pushing the pins outwards would also make it a very easy pick especially with a homebrew tool,

[funboy79015]

Just to add to the idea. Since the pins are moving radially you could add several rows of pins too. So if you had seven pins around and five pins deep in addition to the pin-in-pin idea. I would think that at the very least it would take a lot of time to pick.

[Shrub]

And for the reasons stated above that idea will not work doubly so

[funboy79015]

you can not have a radiused cut like a tubular key as when the key was inserted you would meet the shearline but as soon as you attempt to tun it the pins will be trying to go to a slightly differant height as they are rolled around the bottom of the radius

On the tubular locks I've seen the turning force on the lock is not applied to the pins. It is applied through a ridge on the inside of the key and a nub on the outside of the key so I don't think the quoted reason would be any more of a problem than it is in normal mul-t-locks locks.

With my idea, having a big keyway isn't that big of an issue since it would be a 70-pin lock in which 60 of those pins would have to be repicked every 1/8 of a turn.

[Shrub]

I dont see why i seem to have to explain everything 4 times lately but here it goes again,

The suggestion was to have the pins around the inside of the lock ie perpendicular to the key, if this is wrong then the reason is wrong,

The turning of the lock has no bearing on the explanation i gave,

You could still have the pip or slot that normal locks use to turn the plug,

If you have a pin resting in the side of a hole instead of having a flat bottom hole, the pin will raise or lower (more like rock side to side) when the flat bottom pin moves across the radiused bottom of the hole,

The way described here would require a key that has cuts on the shaft rather than the end like normal ones,

To make the lock actually work properly the pins will have to be pushed in or out to the correct height to meet the shearline, for this to happen the key will have to be like a funnel style,

Actually im bored and give up, you will understand what im on about if this design ever gets made or even if a bit of designing goes in to it,

[raimundo]

the logical extension of this hobby will be when people start making their own lock prototypes to prove these ideas. Since there are people with home workshop who make quarter scale steam engines, it couldn't be that big a streach, oh, right, the home machinest is a different generation, now everyones into computers, so it will have to be an animated graphic of the Idea.

[Shrub]

there are people with home workshop who make quarter scale steam engines,

Been there done that, 1/4, 1/3, 1/2 and now own full size !!!

Making locks would be an interesting hobby but same as you wouldnt raimondo i wont make things that are obviously not going to work.

I will do some drawings to explain myself better on this thread and to why this idea will not work in its present state or it would but the keyway width will be massive and would allow you to push the pins in with any tool and how the lock will be very easy to open.

I am sorry for being short tempered but i think about problems like this in seconds and come up with pro's and con's for the design, it is inbreed to me and also as i have been a mechanical engineer for so long i see things straight away and can visulise the finished products almost instantly and work them in my head, looking at the lock design suggested i immediatley found the main concerns but then did not manage to get my point accross properly to the rest of you,

I will do some sketches and come back better prepared.

[MrB]

See, I think Shrub that you are taking a concept and forming it into a design that won't work; then you are extrapolating backwards and saying that because your design won't work, the concept won't work.

A more positive approach is to take the concept, see the potential problems in your mind's eye, and come up with practical design that will work.

In fact, a radial lock something like the OP said is an old idea, and with a bit of adjustment to the mechanical design it does indeed work. I believe they are called cruciform locks, and the key has four key blades in the shape of a cross, and four separate rows of pins at 0, 90, 180 and 270 degrees. All four shear lines have to be set for the plug to turn. If you were to pick the lock and turn it a quarter turn, all the pins would reengage and you would have to pick all four shear lines again.

[NKT]

If it were something like a cruxiform key, then it would work.

But that isn't how it is described, since the OP says "a tubular lock with ridges", and Shrub is right, it won't work.

Say you take a tube shaped key. You put it in the lock, and turn it. Once turned 45 degrees (with 8 pin stacks), the lock is locked again, only now the key is jammed in it. Since the pin stacks don't move with the key, it just isn't going to happen. And if they do, you are going to need seriously good tolerances to stop the whole thing being a little off-center, which would mean the key would jam again anyway!

If it isn't a tube shaped key, why have one? Go with the cruxiform or H shaped key, or whatever. Otherwise you have a long cylinder down the middle it makes no sense, because, although it turns, nothing else does.

[toomush2drink]

Also you would need to design a new key machine to cut keys

[MrB]

Also you would need to design a new key machine to cut keys

That's going to give you tremendously good key control.

OK: Think of a tubular lock, so the key is a hollow cylinder that fits over a pin in the centre of the lock. Now make the key longer, so it fits more deeply into the lock. Now imagine dimples in rows along the length of the cylindrical key. Finally, let the key have a nub so that the cylinder turns with the key, and so that the key is retained in the lock until returned to the normal position. There is your lock.

Is it worth it? I don't know. Would it work? I think so.