IBM Model M bolt mod help

[MercenarySnake]

Okay so this is my first time bolt modding and I tested the keyboard before I disassembled it, the keyboard indeed worked. I did exactly as all those bolt modding tutorials were telling me to but after I finished the bolt mod and tested to see if the keyboard would work but none of the keys registered. I checked the membranes with a multimeter and nothing seemed off. The leds light up when I plug the keyboard in but then the keys don't register even though the keys make the clicking like they're suppose to, I'm afraid I screwed something up and need help to see what I did wrong.

[hypkx]

Post pictures, maybe you cut some trace on the membran? Have you another controller to test if the keyboard is ok and just the controller bad?

[MercenarySnake]

Post pictures, maybe you cut some trace on the membran? Have you another controller to test if the keyboard is ok and just the controller bad?

Well will these pictures do?

[hypkx]

I think you need a multimeter to check if a trace is broken, Btw you helped me a lot with your post, I have a keyboard with some keys that dont register and I saw on your pictures the reason, that they are all in one row, which means that this trace broken. Thanks for that, now to your problem, check with multimeter the traces, but I think it will b emore likely a problem with the controller. Or the connection, I suggest if you have second model m controller to check if this is the problem. I had the same problem with a model m and other keyboards allready. What converter did you use? A standard ps2 converter?

[MercenarySnake]

I think you need a multimeter to check if a trace is broken, Btw you helped me a lot with your post, I have a keyboard with some keys that dont register and I saw on your pictures the reason, that they are all in one row, which means that this trace broken. Thanks for that, now to your problem, check with multimeter the traces, but I think it will b emore likely a problem with the controller. Or the connection, I suggest if you have second model m controller to check if this is the problem. I had the same problem with a model m and other keyboards allready. What converter did you use? A standard ps2 converter?

Ah you're welcome. I only have one controller which came with the keyboard. I already tested with a multimeter and all of them worked even though some didn't make a beeping noise though the continuity test did show they were working by showing the numbers on the multimeter(sorry I don't know what you would call that). Is there any place I could get ahold of another model M controller or no? Oh and I didn't use a converter, I plugged it into a ps/2 port since my motherboard still has one.

[taylorswiftttttt]

removed

[MercenarySnake]

A couple of questions.
1. How careful were you with the controller while you were working? Did you store it carefully?

2. Are you sure you assembled it correctly? The correct order should be: 1. backplate, 2. membrane with traces facing away from the backplate, 3. plastic sheet with holes, 4. membrane with traces facing towards the backplate, 5. rubber mat, 6. Barrel assembly

In your pictures, there are quite a few places where the traces look fried. Even if they pass the continuity check, you might want to go over them with a conductive pen/tape.

1. Yes I took good care of it and was cautious with it.

2.Oh wow I feel stupid now, I had the first two sheets facing the wrong way. I think that's my problem

I think I'm in need of a new rubber mat too since mine is grey with a lot of white on it and it keeps getting stuff on the membrane sheets, where would I get something to replace that mat at if you don't mind telling me?

Oh and is there anything I can do about a couple cracks which are located on the plastic barrel frame?

[taylorswiftttttt]

removed

[MercenarySnake]

Here is a shitty diagram of the correct order of membrane sheets:



You'll always get it right if you think about it logically. When the traces make contact, a keypress is registered. Therefore the traces must be facing each other with the plastic sheet with holes in between. This means that they are kept very slightly apart, and then when the flipper hits it, they are pressed together and conduct electricity.

If the rubber sheet is falling apart, you can buy a new one from unicomp. I think its on their website somewhere, but for some reason I can't find it.

Ah okay I have them assembled right now thanks to the help you have given me. The sheet isn't falling apart but from what I was reading online the white stuff all over it means it's starting to rot or something like that. On top of it all it smells terrible(unless it's supposed to smell that way). Only problem now is that I got fingerprints on the sheets and the sheet with the holes in it happens to have this dirt dust stuff from the rubber mat.

[taylorswiftttttt]

removed

[fohat]

My guess is that the sheets being in the wrong order was the problem all along. The sheet with holes is what keeps the contacts apart until pressed. Ensure that the contact sides are touching when they are supposed to.

I wipe down the sheets and the rubber mat just for the sake of cleaning them, but you should endeavor to clean the contacts well, but not so aggressively that the metal contact material starts to erode.

[MercenarySnake]

Well I assembled it together like you guys were telling me and it works perfectly, all keys register. Thanks for all the help with the problem I had!