Recoding a door lock

Socrates

Socrates

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Wondering if anyone has experience of recoding a new door lock to an existing key. i.e disassemble the lock and change the pins to match my existing key.

PS1: I’ve done this successfully with other kinds of locks, but not Pebra.
PS2: Subscriber of The Lock Picking Lawyer channel ‍
 
I tried it once and I failed. Since then I let Gerhard from our German forum do this job for me.
What may go wrong:
- you might not have the necessary pistons matching your key
- the locking plates might get damaged during dismantling and you will not be able to mount them anymore.
Regards
Thomas
 
I tried it. As tomhom describes, you'll need to buy a few to have enough tumblers of the right length to match the key shape you desire.

The locking plates are crimped in place.
I tried sliding the plates out from under the crimps, but it wasn't easy.
Recrimping them back in place is also difficult, as the cast material doesn't bend well. I used an extra dab of epoxy glue for it.
 
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Different housing, same procedure
20251113_195232.jpg
 
Rek said:
So I guess this can be done to a boot/trunk key too. I have found that a screwdriver can open mine.
Click to expand...
if a screwdriver can open it, it either has no springs / pins inside or the pins are frozen in the correct position. if they are frozen, perhaps a little spray of a penetrating oil or lubricant might free them up to move - best to use a small straw so you don't get it everywhere, followed by pushing the key in / out several times.
 
TomHom said:
I tried it once and I failed. Since then I let Gerhard from our German forum do this job for me.
What may go wrong:
- you might not have the necessary pistons matching your key
- the locking plates might get damaged during dismantling and you will not be able to mount them anymore.
Regards
Thomas
Click to expand...
I had trouble with piston length, recoding my keys so I eliminated those that didn’t “fit.”
 
Couple years back i recoded several sets for e9 with a good result, in general to make one good set you need two average or even more bad sets, some pins are damaged/rounded or bent, some pushers or springs are absent, sometimes also inner rotor/barrel is so scratched that it might be unusable, due leveling, same with pin holes.
The best donor for parts is a glovebox lock (due to it little usage).
Pretty precise & time consuming work - springs are flying everywhere while case closing, so flashlight & nerves of steel are must have.
 
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if anybody takes one apart, please measure the diameter of the pins ... also measure the diameter of the cylinder tube. with residential type locks, when removing the cylinder, you push a rod in the other side to keep the springs / top pins from flying out. the top pins aren't as big, but they keep the springs from going into the cylinder and damaging the springs. the bottom pins are what go into the holes of the key and if they are flush with the cylinder, the lock will turn.

with the cylinder out, and the key in place, all of the pins must be flush with the surface of the cylinder. if the pins are too long, you can file / grind them down ... if they are too short, there is a problem.

if when removing the cylinder, you don't push a tube in (to keep the springs / top pins from flying out), you can use a pair of tweezers to load the slots (one at a time) and cover the slot with the cylinder and keep going until they are all in.

if you don't have the key, you have to remove the covers off of the outer assembly - if you do this, do it inside of a plastic bag so you catch all of the springs + pins.
 
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Fascinating! This is what I love about this site. You guys do the most amazing things and think nothing of it. I have no talent or patience for this sort of process. I can do the macro stuff, change oil, replace bulbs, etc. But when it comes to the fine micro work, the jeweler work, I am lost.

But fortunately for me Bill lives about five miles away across the Delaware River in NJ. We shared a true barn find, a 1974 CSi. I did what I was told, Bill did the rest, a successful adventure for both. People like me need a Bill. thanks Bill
 
I replaced a door lock tumbler in my (long gone) 88 635. This lock was somewhat differently constructed, but the principle was similar.

Someone had buggered the driver side door lock, so I decided to fix it. I got a lock kit from the BMW dealer. It came in a bag that was labeled "not for public sale" but they sold it to me anyway.

In the bag were the various tumbler parts including springs and small slotted wafers (the 635 tumble uses wafers instead of pins). The wafers slid into an array of small slots in the tumbler. They had different lengths of tabs on either side of the slot, and small springs on the sides. When no key was in the tumbler, one side of each wafer stuck out of the slots.
Screenshot 2025-11-16 at 9.38.19 AM.png


The key was double sided, so when it went in it would move the wafers one way or the other causing the extended wafer tabs to slide into the tumbler some distance based on how the key was cut. I had the key, but had no idea which wafers should go where. So this was basically a trial and error exercise. Put in the wafers, slide the key in, see which, if any wafers retracted properly, Set that wafer aside in a labeled spot, based on which wafers did what, re-arrange them, and try again. It took about 20 minutes to finally get the right wafers in the right spots and in the right orientation. It truly felt magical when I got it right and when the key went in, all of the wafers disappeared into the tumbler.

With the key in the tumbler, I then sld the tumbler into he door latch housing, and connected the back side to hold the tumbler in place.

I do recall that you had to be super careful about holding the assembly or all the wafers and springs woudl fall out and you had to start over.

I am pretty sure the pin version of this used in the E9 is similar...
 
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