Modding the lock on my 1971 Nishijin "A"

[SteveFury]

I want to build a semi-sealed cabinet for my vintage pachinko so I wanted to fix the lock so any screwdriver or properly grooved flat key will open it. I suspect it is a common lock for the period with a crooked keyhole.

First is a couple photos of the lock itself, the lock has a number 7 stamped on the rear:
Front.JPGRear1.JPGRear2.JPG

The lock is held together by 4 expanded tabs shown below:
SplitTab.JPG

Using a big channel lock pliers, I was able to squeeze the spits on each of the 4 tabs enough to pry it apart with a common screwdriver:
Opening.JPG

The 3 plates inside are arranged this way (The parts had fallen out when I took it apart but this is how the inside plates went):
Parts.JPG

The cylinder contains no springs or actuators like a traditional lock does. All the key does is go flat with the bottom plate, and when you turn the key it will directly move the slider which actuates the external door latch mechanism. Extremely simple.

It has two additional spring loaded plates which keep the key inserted while being turned.

In order for me to be able to open the lock by only turning the key shaft with a screwdriver, I had to make a tab to fit the bottom of the key slot.
I used a large size steel nail for the tab material. I ground the nail flat on two sides just enough to fit very snuggly into the key slot to stick out like a key would have.
Note: I took particular care to make it the correct length to properly fit into the slot in the slide. I did a bit more grinding to ensure a proper fit for operation.

I then mixed up a spot of "JB WELD" which is the strongest epoxy I've ever seen and applied it to the end of the steel pin I made and glued it into the key slot. The fit was very tight and I used a pliers to ensure the steel pin sank to the very bottom of the slot. I wanted a very tight fit because this is a potential breaking point and it simply MUST be tight.
Below is how the steel pin looks as the epoxy cures:

Actuator.JPG

You can see below how the key slot and steel pin move the lock slider:
ActuatorInPlace.JPG

I will be discarding the two extra plates which keep the key from being removed while operating the lock since I don't need them anymore. Besides they just get in the way of my steel pin and prevent it from working properly.
I needed to compensate for the space these two plates formerly occupied so I added a couple shiny washers to keep the slide flat against the bottom. (See below)

Washers.JPG

That's it, I am waiting for the epoxy to finish curing before reassembling and testing.

A few light taps of a hammer should be enough to squeeze the 4 split tabs which hold the lock together- enough at least to reassemble the lock.

I haven't tested this mod yet but I'll let you all know how it goes in a day or so after the epoxy has completely cured.

[SteveFury]

The two plates I am removing probably doesn't prevent the key from being removed, the slot on the front of the lock should serve that function.

The two plates would more likely be to facilitate different key numbers to fit different locks of the same type. All it would take would be for the slot on the end of them to be formed differently.

But in my case, my lock with a 7 stamped on its back would only need a key with a properly shaped slot long enough to fit to the bottom of the lock to work. The bottom of the key would need to be flat not pointed, and a single slot cut near the handle side of the key to allow it to turn.

[SteveFury]

Ok this modification is a success. It works perfectly and I can open the pachinko machine with only a small screwdriver.

The only additional thing I did was to remove the slider return spring. The spring is very heavy and it adds a lot of unnecessary resistance against the metal tab I made. The function of the spring is to return the slider back to its original position after unlocking the lock. The slider is very loose and floppy, and it faces upward in the cabinet anyway so gravity naturally returns it. I added just a bit of thin non-petroleum grease to the mechanism before reassembly.

This is the spring I removed. The only two moving parts in the modified lock is the key shaft and actuating lever.
Return Spring.jpg

[mxfaiman]

Okay. I'll say congrats to you on figuring out a different way on opening the lock.

I have been playing around myself with making keys for the Nishijin locks. So far the straight locks are easy to make the keys for it is the angled ones that are a tad bit harder.

I'll tell you all now the magic key blank that fits in these locks. It is made by HY-KO, it is a KK2. Or in other words a key for a KIA Sportage.

There is a few mods you need to make to the key. But once you make one with all the proper sized slots any lock smith should be able to copy it. ( Just don't go to Ace they have the wrong type of grinder. It has to be a V grinder not a square.)

I'll post another update later today with pictures of my angle lock (I have to find it, it is here somwhere.) And the rest of my instructions.

For now I have some pictures attached below.

1. Picture of a straight lock
2. Key original blank and prototype key.
3. Key blank for pachinko lock
4. Final key. (minor adjustments need to be made)

[mxfaiman]

Sorry I've been a little busy lately.

I also can't seem to find my modded angle lock. (It is here somewhere.)

If I have some time. I'll find the key I cut and make a full size pattern and upload it here. I have just been using a dremel with a cutting disk and a file to make the keys (note: use a small file. and make sure it is made for metal.)

I'll update a little later if I have some time.

[mxfaiman]

Okay I had a little time so I made a pattern on which shows you EXACTLY where to cut the key. (file attached)

What to do:
1. Buy you key(s)

2. Print out pattern. (make sure the 1/8" box is the right size)

3. Using the pattern mark where you need to cut the tip off the key.

4. Use the pattern and mark the lines the need to be cut out. (The Red lines) AlsoNote: cut ON the red lines don't cut next to them. If you do the key may turn out wrong.

5. Cut on the lines you made on your key.

6. Test fit your key in the lock.

7. If it is a little snug in some spots. Find the area that may be the problem and take your file and grind it down a little. (Other attached file: The Blue arrows show areas where you may need to file.)

8. Repeat steps 6 and 7 if needed

9. If you key fits perfect and can open your lock. Congrats your done.

If anyone has any questions feel free to ask.

I'll keep looking for my angle lock to show you my mod.

[Drunkenclam]

Out of interest. There is a set of Nishijin keys on YJA. I'm off to my locksmith tomorrow for work. Will see if he has one of those key blanks

¥ì¥È¥íµ¡!¥É¥¢¥*¡¼¡ªÀ¾¿ØÂ渰//£°£°£±¡Á£°£°£µÈֳƼ´õ¾¯ - Yahoo!¥ª¡¼¥¯¥·¥ç¥ó

[mxfaiman]

Hmm.Those keys look like they may work. Though finding a blank like that is almost unexhistent in the US.

[Drunkenclam]

I mean I'll see if I can get that KIA blank here in the UK

[mxfaiman]

You should be able to find it. It is fairly common.