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Hi:
This is my first post as a new member.
I've been studying the 1905 and 1925 Miller catalogs from your web site. On the Champion 6-lever pdf page 32 of the 1905 catalog it mentioned "Unlimited Key Changes" but on the next page "Champion 4-lever" is says "120 key changes", then on pdf pg 34 "Empire 6-lever" is says "12 key changes". What are key changes?
http://www.prc68.com/I/Locks.html#Lever_Pancake_Padlock
Have Fun,
Brooke
The number of different keys that are available for a particular lock. I believe these are known as "differs" in the UK.Quote:
Originally Posted by brookeclarke
The variations in the "bittings" of a key, and the corresponding variations in the tumblers or wards of the lock, are designated by the term "key changes". Thus, a cheap warded lock, having only four variations, is said to have four "key changes".*
*from Yale & Towne Mfg. Co. Catalogue No. 26, (c)1929, pg. XXXII.
Pete Schifferli
note to BBE: perhaps this should be added to the LIST Council Locksmith Dictionary?
Hi Pete:
That's what I thought but seems to be inconsistent with my Miller Champion 6-lever lock which is listed as unlimited while the "Champion 4-lever" is "120 key changes", then on pdf pg 34 "Empire 6-lever" is "12 key changes".
From what I've read the 6-lever locks have 6 levers and each lever can have up to 6 different notch locations. So it would seem that the maximum number of key changes can be 6 * 6 = 36. Maybe less if the key can be inserted upside down.
Maybe the Champion 4-lever has 30 notch positions on each lever?
I can see how the number of key changes can be less than the maximum possible, but don't see how there can be more than the maximum and "unlimited" seem way to many.
Have Fun,
Brooke
this is inside of an L&N railroad 6 leverAttachment 17357this might be 16 changes
Obviously they were mathematically challenged, or they just lied. You are correct, 6 lever = 36 possibilities, 4 lever = 24 possibilities. It is entirely possible they limited the Empire to 12 possibilities.Quote:
Originally Posted by brookeclarke
BBE.
Thanks for noticing Pete. Many years ago it was in there, looks like some cut and paste may have gotten rid of it. I'll see if I have a printed version from the 80's, if not I have started the process to add it.Quote:
Originally Posted by Pschiffe
BBE
Not all theoretical key changes may be manufactured for a number of technical reasons. These might included all identical cuts exposing the lock to being easily picked as well as too many deep cuts that could weaken the key. Thus the actual number of key changes is likely to be less than the theoretical number.Quote:
Originally Posted by BBE
Pete Schifferli
As I see it, a 6 lever lock with 6 possible notch locations on a lever would mean 6x6x6x6x6x6=46,656 differs, assuming there are no other restrictions upon the key space.Quote:
Originally Posted by brookeclarke
...Mark
also a friend told me his 4 lever champion had 5 levers,i took one apart and it did have 5 levers but worked with the 4 cut push key ?
forgot to add i also have a 6 lever champion with only 2 of the levers having double cuts.
I don't understand that. Looking at the key there are 6 unique positions (assuming the entrance slot acts as warding so the key can not be used up side down) and for each of those positions 6 possible depths of cut for a total key space of 36 possible keys.Quote:
Originally Posted by mercury
Well, I don't know what I was thinking before, you are absolutely right. The full potential for the 6 lever lock is 46,656. The actual changes will be somewhat less, probably around 20% because the key can be reversed and you wouldn't want 6 1's, or 2's, etc.Quote:
Originally Posted by mercury
BBE.
Consider a key for a lock with just two levers, with 6 possible cut depths.Quote:
Originally Posted by brookeclarke
For each of the 6 possible cuts for the first position, there are 6 possible cuts for the second position. This gives 6x6=36 differs which could be represented as follows :
1,1 1,2 1,3 1,4 1,5 1,6
2,1 2,2 2,3 2,4 2,5 2,6
3,1 3,2 3,3 3,4 3,5 3,6
4,1 4,2 4,3 4,4 4,5 4,6
5,1 5,2 5,3 5,4 5,5 5,6
6,1 6,2 6,3 6,4 6,5 6,6
For a key with three levers, 6 possible depths, we can take the 36 possible two lever keys and multiply by 6 for each possible cut for lever 3. Therefore there are 6x6x6=216 possible keys.
The same logic gives us 6x6x6x6=1296 possible keys for a 4 lever lock, 6x6x6x6x6 for a 5 lever lock and 6x6x6x6x6x6 for a 6 lever lock.
As BBE explained, not all of these theoretical differs will be used for various reasons.
I hope that clarified this and not made it more confusing instead!
...Mark
Hi Mark:
I don't see it. What are the numbers in the table?
1,1 1,2 1,3 1,4 1,5 1,6
2,1 2,2 2,3 2,4 2,5 2,6
3,1 3,2 3,3 3,4 3,5 3,6
4,1 4,2 4,3 4,4 4,5 4,6
5,1 5,2 5,3 5,4 5,5 5,6
6,1 6,2 6,3 6,4 6,5 6,6
You show the first number AND the second number ranging between 1 and 6. It seems to me that if the first number is the wafer/lever and the second number is the cut on that wafer/lever then the table represents the 36 possible keys for a 6-lever lock.
Another way to look at it is when assembling a lock you can choose from 6 different levers for the first position, then again you choose from 6 different levers for the second position, and so on with only 36 possible ways to assembly the lock.
Have Fun,
Brooke
Each pair of numbers represents the cut depth for lever one and lever two as follows (depth for lever one, depth for lever two).Quote:
Originally Posted by brookeclarke
So 1,1 means a cut depth of 1 for both levers.
1,2 means cut depth 1 for lever one, cut depth 2 for lever two.
4,6 means cut depth 4 for lever one, cut depth 6 for lever two.
The list I made above represents all 36 possibilities for a two lever lock.
...Mark
Mark
Just some question to ask. It is probable could have an "O" cut?......Timothy......
Mark has a good explanation below your post. The problem was that HTML removes extra spaces or tabs and makes tables sort of screwy looking. This illustrates it better.Quote:
Originally Posted by brookeclarke
BBE.
Hi: What is the meaning of those numbers?
It looks to be for 6 wafers/levers where each has 6 possible notches.
Have Fun,
Brooke
Each pair of numbers represents a key for a two lever lock that has 6 possible cut depths.Quote:
Originally Posted by brookeclarke
The first number in each pair represents the cut depth for lever one. The second number in each pair represents the cut depth for the second lever.
For example 4,6 would mean cut depth 4 for lever one and cut depth 6 for lever two.
Six numbers would be needed to use this system to describe a 6 lever key.
Thank you for making that table, BBE.
...Mark
Hi:
I see. So the listed "key changes" for the Miller locks are not based on the number of possible different keys, but on something else.
Have Fun,
Brooke
Hi: The key has no stop, that's to say it is just pushed until the lock opens. That means the relative bit depths are important and the absolute depths do not matter. For example a lock with two wafers could have 36 possible keys if there was an absolute reference, like in a pin tumbler. Bot for a lever lock with two wafers there are only 11 unique keys (fewer of you can flip the key over). I have not figured out a general formula, got the 11 by listing all of them.
http://www.prc68.com/I/Locks.html#Lever_Pancake_Padlock
Have Fun, Brooke
Attachment 17553
the 3 keys here have had the stop removed for various reasons, all keys for these pancakes 4-6-8 lever did have stops as the new and used keys and blanks show
sorry, i have seen a few eagle with straight keys . i do not know if they were original and there were a couple others that had side and or a notch in the center
i have a nhc ,miller secure push keys and s/b and crank push keys with no stops.
the yale 633,and baffler keys do have stops,
apparently some do and some do not,enjoy the site and have fun collecting. the gentlemen here have a wealth of knowledge and understanding
I think that if the stops on the blank keys are left in place then the number of "key changes" would be much higher, but the stop works like warding so when removed the number of key changes drops a lot. In the case of a skeleton key the number of key changes drops to 1.Quote:
Originally Posted by nathanbonstein
Have Fun & Thanks for the photo.
PS How are push keys cut?