Sat Oct 17, 2009 9:10 pm
Cutting Lever keys by hand
This applies mostly to those of you confident with cutting keys for inline pin cylinders by hand. Same skills, but levers are something completely different.
How many blanks would you think you've used\destroyed learning to cut for inline pin locks?
Roughly the same as that before you'll really get proficient at cutting lever keys. (for all sorts of locks)
If you're only cutting keys for one particular lock, or one brand of lock, you will pick it up fairly quickly, in three or four blanks.
Selecting a blank is important, though mostly if you can get the manufacturer of the lock, it will slim down the choices by a great deal.
Check how many levers are in the lock, and the size of the pin\pipe gauge.
Pin\pipe sizing and flag length\hight are best left to your local locksmith.
Also how easily you can cut a key depends how you can access the lock. If you can strip it down to the bolt and one lever, you've got an easy job.
If you're impressioning it, without removing any parts, it's a lot harder to learn.
Anyway, as a rough guide you should be following this basic outline:
Remove all components in order (assuming the combination is to be kept. Do this anyway, even if changing the combination, to force the habit)
Lay them out in a line of removal (left or right does not matter, just whatever you remember) starting with any case screws, then the casing itself, followed by any curtains or springs, second-last is the levers themselves, and lastly the bolt. (some locks have mid-range bolts, with levers under it. modify this layout pattern to suit)
After removing all parts in sequence, clean the back plate\casing lightly with a file, just dress it up a bit.
Also the bolt can have some damage to the talon (where the bolt-throw part of the key fits into the bolt, when turning) so this can be filed and repaired now.
After the bolt is moving smoothly in the casing, you can lubricated it and install it.
All lever lock lubrication should be dry powdered graphite, no exemptions.
This is done by laying a sheet of copy-paper on a flat surface and dusting it with the graphite powder.
Then you rub the bolt or levers onto the paper, to give them an even coating of graphite.
Never primarily just puff the powder at the levers, it does little help. In sections such as the top side of the bolt, where the first lever will contact it, you can puff some on to reduce friction. (Can't rub it on the paper most times)
With only the bolt in the rear casing, insert your key and check for hight of the flag. Most times you will only need to take minimal amounts off the top, for it to throw the bolt fully.
You're wanting to get the very end of the key to swing into the talon and throw the bolt all the way out, and all the way back in. Take this step very slowly. Filing too much off at this point will destroy the key. Hight of the bolt throw is 99.9% the highest cut possible on the key, so once it has been found, continue that hight across the key.
Assemble the casing now, and insert your key. It should insert freely and turn. If the flag is too wide, you may need to shorten it so that it does not contact the front of the casing. Manufacturers often make them slightly bigger, to allow for any problems.
Pin and Pipe key blanks only need the back of the flag (closest to the head of the key) modified.
Mortice key blanks (with a collar between the flag and the head) often need the front, the back, or both modified.
Levers. If you're going to change the combination, do so now. Attempt to keep any similar depth levers away from each other by at least 1.
Starting with the first lever (one closest to the bolt) you will first De-grease with your cleaning spray of choice, then lightly file both flat sides of the lever. This cleans any edge burrs or inconsistencies.
After that, hold your file at a 45 angle (best done with an impression file) to the belly of the lever (the half-circle part that contacts the key) and file the very edge off. You're not looking to make and serious modifications to the lever, just to put a very small bevel on the edges. Do this on both sides of the lever.
This allows the lever to slip down into the cuts of the key, if it's not perfectly cut. Also it prolongs the life and stops levers getting stuck together (the bellies flare out just like the head of a chisel)
Check the spring, these can work loose and loose tention. Replacement is relatively simple on most.
Once cleaned and repaired, you can lubricate in the same manner as the bolt, by rubbing against dusted paper. Install the lever, and re-insert your key.
This is all done without the top casing on, being careful to maintain a straight and aligned key.
Turning the key, the lever will contact the flag and you can take note of the height of cut needed, and the spacing of that lever. (Some locks have different thickness levers)
I coat my key with a blue permanent marker, but smoke and marking-dye can be used.
With time and experience, simply looking at the mark left on the key can give an indication of cut depth.
This is where the repair to your levers comes in, as you should have even, solid lines marked out by your levers on the key.
If not, visually inspect the lever for burrs and flares on the belly. Fix this now.
Be very careful to file straight, and slow. There is no rushing lever keys, they take time.
Never file straight down to the level you think you need, always back off a 1mm or so. This is to be allowed for rounding.
Rounding is employed on lever keys to account for wear and allow smooth operation of the key.
This can be done simply by holding the key in one hand, the file in the other, and rocking it against an object while filing back and forth.
For most cuts, the rocking should only be from 11:00 to 1:00.
Cut rounding
This step is highly important. This takes practice, and time.
This is the stage where you finally take the cut down to the right depth, allowing smooth rotation and bolt retraction, where the lever isn't blocking any movement.
Filing too low at this stage is only an issue if you cannot change the combination, or have no deeper levers. If this happens, start with another key.
When the first lever is done, temporarily install the front plate of the casing, and test the key. Though sometimes the lever will move around on the pivot post, it should give you an idea of whether or not you have cut the key correctly.
If you can turn, but it is binding, you have not cut deep enough. If you get a click, then free turning, you have cut too deep.
If you get no turning, either your bolt is too long, or you have cut much too shallow\deep.
To help this, be sure to keep the key straight in the casing when the top plate is removed.
The second lever is much the same, but you must ensure the levers are all flat against the bolt. Allowing them to ride up will cause spacing issues when you finally reassemble the lock.
Always clean, repair and inspect the levers when you are installing them. Malformed or damaged levers can cause issues when the lock is reassembled and may not manifest until you've reinstalled it in the job. On safes and vaults, you don't want this.
As you work through the levers, often check the key with the casing fully assembled. Bearing it mind that the more levers you have installed, the more they will move around on the pivot post (unless you have them all installed) this will give you a good idea of how well the key is working, and if anything needs to be changed.
Deeper cuts can be wider than shallow cuts. This means the levers can drop down into the deep cuts without grabbing the shallower cuts. Shallow cuts must not overlap into deeper ones, as this can pick up the lever and stop the key turning.
When you've installed all the levers, and you've got a working key, assemble the lock finally and check the operation.
When satisfied with the workings (it should be smooth and without binding, grabbing, jumping or clicking), hold pressure on the bolt at the retracted position, and turn the key to extend the bolt.
If the bolt falls back to the retracted position, when you've turned the key, your bolt throw is too short. Start with a new keyblank.
If the bolt stays locked out, you have a working key.
How many blanks would you think you've used\destroyed learning to cut for inline pin locks?
Roughly the same as that before you'll really get proficient at cutting lever keys. (for all sorts of locks)
If you're only cutting keys for one particular lock, or one brand of lock, you will pick it up fairly quickly, in three or four blanks.
Selecting a blank is important, though mostly if you can get the manufacturer of the lock, it will slim down the choices by a great deal.
Check how many levers are in the lock, and the size of the pin\pipe gauge.
Pin\pipe sizing and flag length\hight are best left to your local locksmith.
Also how easily you can cut a key depends how you can access the lock. If you can strip it down to the bolt and one lever, you've got an easy job.
If you're impressioning it, without removing any parts, it's a lot harder to learn.
Anyway, as a rough guide you should be following this basic outline:
Remove all components in order (assuming the combination is to be kept. Do this anyway, even if changing the combination, to force the habit)
Lay them out in a line of removal (left or right does not matter, just whatever you remember) starting with any case screws, then the casing itself, followed by any curtains or springs, second-last is the levers themselves, and lastly the bolt. (some locks have mid-range bolts, with levers under it. modify this layout pattern to suit)
After removing all parts in sequence, clean the back plate\casing lightly with a file, just dress it up a bit.
Also the bolt can have some damage to the talon (where the bolt-throw part of the key fits into the bolt, when turning) so this can be filed and repaired now.
After the bolt is moving smoothly in the casing, you can lubricated it and install it.
All lever lock lubrication should be dry powdered graphite, no exemptions.
This is done by laying a sheet of copy-paper on a flat surface and dusting it with the graphite powder.
Then you rub the bolt or levers onto the paper, to give them an even coating of graphite.
Never primarily just puff the powder at the levers, it does little help. In sections such as the top side of the bolt, where the first lever will contact it, you can puff some on to reduce friction. (Can't rub it on the paper most times)
With only the bolt in the rear casing, insert your key and check for hight of the flag. Most times you will only need to take minimal amounts off the top, for it to throw the bolt fully.
You're wanting to get the very end of the key to swing into the talon and throw the bolt all the way out, and all the way back in. Take this step very slowly. Filing too much off at this point will destroy the key. Hight of the bolt throw is 99.9% the highest cut possible on the key, so once it has been found, continue that hight across the key.
Assemble the casing now, and insert your key. It should insert freely and turn. If the flag is too wide, you may need to shorten it so that it does not contact the front of the casing. Manufacturers often make them slightly bigger, to allow for any problems.
Pin and Pipe key blanks only need the back of the flag (closest to the head of the key) modified.
Mortice key blanks (with a collar between the flag and the head) often need the front, the back, or both modified.
Levers. If you're going to change the combination, do so now. Attempt to keep any similar depth levers away from each other by at least 1.
Starting with the first lever (one closest to the bolt) you will first De-grease with your cleaning spray of choice, then lightly file both flat sides of the lever. This cleans any edge burrs or inconsistencies.
After that, hold your file at a 45 angle (best done with an impression file) to the belly of the lever (the half-circle part that contacts the key) and file the very edge off. You're not looking to make and serious modifications to the lever, just to put a very small bevel on the edges. Do this on both sides of the lever.
This allows the lever to slip down into the cuts of the key, if it's not perfectly cut. Also it prolongs the life and stops levers getting stuck together (the bellies flare out just like the head of a chisel)
Check the spring, these can work loose and loose tention. Replacement is relatively simple on most.
Once cleaned and repaired, you can lubricate in the same manner as the bolt, by rubbing against dusted paper. Install the lever, and re-insert your key.
This is all done without the top casing on, being careful to maintain a straight and aligned key.
Turning the key, the lever will contact the flag and you can take note of the height of cut needed, and the spacing of that lever. (Some locks have different thickness levers)
I coat my key with a blue permanent marker, but smoke and marking-dye can be used.
With time and experience, simply looking at the mark left on the key can give an indication of cut depth.
This is where the repair to your levers comes in, as you should have even, solid lines marked out by your levers on the key.
If not, visually inspect the lever for burrs and flares on the belly. Fix this now.
Be very careful to file straight, and slow. There is no rushing lever keys, they take time.
Never file straight down to the level you think you need, always back off a 1mm or so. This is to be allowed for rounding.
Rounding is employed on lever keys to account for wear and allow smooth operation of the key.
This can be done simply by holding the key in one hand, the file in the other, and rocking it against an object while filing back and forth.
For most cuts, the rocking should only be from 11:00 to 1:00.
Cut rounding
This step is highly important. This takes practice, and time.
This is the stage where you finally take the cut down to the right depth, allowing smooth rotation and bolt retraction, where the lever isn't blocking any movement.
Filing too low at this stage is only an issue if you cannot change the combination, or have no deeper levers. If this happens, start with another key.
When the first lever is done, temporarily install the front plate of the casing, and test the key. Though sometimes the lever will move around on the pivot post, it should give you an idea of whether or not you have cut the key correctly.
If you can turn, but it is binding, you have not cut deep enough. If you get a click, then free turning, you have cut too deep.
If you get no turning, either your bolt is too long, or you have cut much too shallow\deep.
To help this, be sure to keep the key straight in the casing when the top plate is removed.
The second lever is much the same, but you must ensure the levers are all flat against the bolt. Allowing them to ride up will cause spacing issues when you finally reassemble the lock.
Always clean, repair and inspect the levers when you are installing them. Malformed or damaged levers can cause issues when the lock is reassembled and may not manifest until you've reinstalled it in the job. On safes and vaults, you don't want this.
As you work through the levers, often check the key with the casing fully assembled. Bearing it mind that the more levers you have installed, the more they will move around on the pivot post (unless you have them all installed) this will give you a good idea of how well the key is working, and if anything needs to be changed.
Deeper cuts can be wider than shallow cuts. This means the levers can drop down into the deep cuts without grabbing the shallower cuts. Shallow cuts must not overlap into deeper ones, as this can pick up the lever and stop the key turning.
When you've installed all the levers, and you've got a working key, assemble the lock finally and check the operation.
When satisfied with the workings (it should be smooth and without binding, grabbing, jumping or clicking), hold pressure on the bolt at the retracted position, and turn the key to extend the bolt.
If the bolt falls back to the retracted position, when you've turned the key, your bolt throw is too short. Start with a new keyblank.
If the bolt stays locked out, you have a working key.
