IBM Model F AT Key Issues After Foam Change?

[johnny0731]

Hello,

So I decided to change the foam for my model F AT to the 2mm "art foam" from Michael's as suggested by many. My original foam was completely broken down, and I have been using some really thin "shipping foam" that I had lying around for the time being.

I managed to change the foam and reassemble the keyboard. The thing is, for some reason, the springs for long horizontal keys (left shift, numpad 0) are not buckling. I don't think the issue is with the spring/hammer being misaligned, because when I put in 1U keys at these places they buckle and register properly.

I also changed the backspace/backslash/enter keys to Model M ANSI keys, and these keys seem to be binding a little bit. For example, when I press the far left "non-spring" part of the backspace/enter key, it doesn't click as well.

I think the issue might be with the stabilizer clips blocking the key from being fully pressed down, or the "wire insert" part on the keycaps bottoming out before the key clicking. For example, when I put a 1U key in the barrel for left shift, and when I press the top part of the key, it works fine; but when I press the bottom part, it binds and doesn't buckle really well.
But then again, right shift key works fine for some reason...

Has anyone faced this issue after changing their foams? Any ideas on possible causes/solutions? I've tried reseating the keys many times, am I just doing it wrong every time?

[Fkazim]

Maybe the stabiliser insert in not pressed in all the way. Meaning that the key cannot go down far enough to buckle the spring. double check that the insert is fully pressed in so it is flush with the key barrel

[fohat]

I think that you have a stabilizer problem. Sometimes you have to use a small flat head screwdriver to guide the wire into the tab as you are seating the key. That can get frustrating but put on your reading glasses and do it in bright light.

Also, did you remove and replace any stabilizers and possibly turn them around so that they are no longer facing in the right direction?

[Fkazim]

fohat he replaced some of the larger keys with ANSI keys from a Model M meaning he now has the rod stabiliser type keys not wire stabilisers from what I understand.

Also johnny0731 yes the old stabiliser clips will interfere with keys after a foam replacement. I had this issue with my F AT after I replaced the foam and had to remove the stabiliser clips. It was fine for me anyway because I used a Model M keycap set with rod stabilisers.

[johnny0731]

Thanks for all the replies! The problem is for horizontally long keys with wire stabilizers, specifically left shift and numpad 0. (but right shift works fine?) The the Model M keys (backspace, enter, backslash) are working, albeit with a different key feel for some reason?

As for the stabilizer wire not going into the insert, I'm not sure if that is the issue because even if I take out the wire stabilizer completely and just put in the keycap by itself, it still doesn't work. Even with the stabilizer, I checked that the wires are inserted into the insert properly, but no luck.

I think the issue might be with the "protrusions" on the left shift/numpad 0 keycaps that hold the wire stabilizers, as they might be bottoming out before the keys buckle. Putting 1U keys without those protrusions in the barrel for left shift/numpad 0 works fine, so maybe I'll try getting some Model M keys with rod stabilizers. Maybe I'll try to take out the clips, but I'd really like to not take apart the keyboard and reassemble the spacebar...

I really tried pushing the stabiilzer inserts/clips really hard, but can't seem to push it further. Maybe I'm just not strong enough?

I'm really not sure why changing the foam would suddenly cause these issues, but I guess it's not something unique to me. I'll try to get hold of some Model M left shift keys and see if that solves the issue!

[Weezer]

The wire stabilizers shouldnt affect anything, if theyre seated properly. IBM didnt skimp on engineering back in the day and they wouldnt design a key that bottoms out before it actuates.

Try tipping the keyboard back so only the cable coming out of the rear of the keyboard is touching the ground or table, then once the keyboard is tipped this way try fully taking off the keys in question and reinserting them.

If this fails, did you put the spring in the right barrel? This can be easy to mess up with the wire stab keys because theres no peg to alert you that the spring is in the wrong hole.

[Redmaus]

I always just removed the wire stabilizers and replaced them with the insert ones for better cap compatibility. I'm pretty sure you could completely remove the wire stabs without disassembling the keyboard, as they pop out face up on the plate. With some good pliers after removing keycaps surrounding the immediate area.

I'd follow Weezer's suggestion first, as I have had the same thing happen after screw modding M's and tipping the keyboard back always resolves this issue.

[SneakyRobb]

The wire stabilizers shouldnt affect anything, if theyre seated properly. IBM didnt skimp on engineering back in the day and they wouldnt design a key that bottoms out before it actuates.

Try tipping the keyboard back so only the cable coming out of the rear of the keyboard is touching the ground or table, then once the keyboard is tipped this way try fully taking off the keys in question and reinserting them.

If this fails, did you put the spring in the right barrel? This can be easy to mess up with the wire stab keys because theres no peg to alert you that the spring is in the wrong hole.

Hi agree, Would you be able to take a picture of the numpad 0 and left shift keys when removed?

[orihalcon]

This might seem kind of basic, but did you put the hammer under the correct barrel for these multi wide keys? The cap won’t orient the spring in the right position if it’s under the wrong barrel. Also explains why putting a single unit cap over the spring DOES work.

[fohat]

You probably realized that Model M wires are much thicker than F wires and are not compatible at all, but that is not likely the problem. They are also different lengths so that you can't use the smaller wires in the larger tabs, but that won't be your problem either.

My advice is to switch to Model M keys with barrel insert stabilizers for everything but the space bar.

And yes, it is imperative that the springs are in the proper barrels.

[johnny0731]

Thank you for so much help!

Good news is that the numpad 0 now works and clicks fine! Bad news is that I have absolutely no idea what I did differently. Maybe it was an issue with the spring being aligned with the stems? It suddenly works now, which I guess is okay?

As for the left shift, it's still not clicking as it should be. I tried tipping the keyboard and reinserting, but the same results. Here are a few pictures of my left shift key:

First of all, when the shift key isn't pressed:

Left shift key when not pressed

lshift_notpressed.jpg (2.89 MiB) Viewed 3350 times

Left shift key when not pressed

lshift_notpressed2.jpg (3.65 MiB) Viewed 3350 times

I think the wires are in the appropriate clips. It might be easier to see when the shift key is pressed:

Left shift key when pressed

lshift_pressed.jpg (2.83 MiB) Viewed 3350 times

As for the spring/hammer location, I think this is the right barrel?

Spring location for left key

lshift_spring.jpg (3.51 MiB) Viewed 3350 times

Finally, when I do this, it clicks/registers fine:

Putting 1U key (which works fine)

1u_key.jpg (4.42 MiB) Viewed 3350 times

I know the pictures aren't the best quality, but they were my best attempt using a bad phone camera. Please let me know if I'm overlooking something very obvious

I'll try to get hold of a insert stabilizer left shift keycap from model M, but I guess until then I'll be using it with that 1U key inserted!

[Weezer]

Thanks for the pics

In the picture "lshift_spring.jpg" is the keyboard tilted backwards fully? It looks like the spring is still facing forward. If the spring moves freely in an identical way to the spring for caps lock, but isn't centered in the barrel when you tilt the keyboard back, use a toothpick to push the spring towards the back of the barrel as you're inserting the key. The idea is to get the spring to seat properly in the little notch on the bottom of the key cap which is what happened with the 0 key.

If that doesn't yield any results, the next easiest option that I can think of might be to take the keyboard apart and SWAP the spring from the a 1U key to the left shift as you have the stabilizer inserted correctly and the 1U keys and the left shift are the same height.

[orihalcon]

Agree, spring is in correct barrel, tilting keyboard back as far as possible while you put the cap on often is needed for certain keys. I’m talking very tilted back like perpendicular to the ground. You might also want to examine the inside of your shift keycaps as well. I’ve seen a few instances where the little nub that orients the spring is gone and in that case would be a problem with the cap itself and would just need to be replaced.

[Weezer]

I’ve seen a few instances where the little nub that orients the spring is gone and in that case would be a problem with the cap itself and would just need to be replaced.

I suspected this as well, but I figured it was unlikely. I didnt know that it was a common occurrence!

[johnny0731]

It's been a busy couple of days so I couldn't really mess with my keyboard, but I've tried tilting the keyboard upright and then put in the shift key. Unfortunately no luck

Here are the pictures that I've taken to illustrate my attempt. I try to put the springs in the stem of the keycaps:

insert1.jpg (3.14 MiB) Viewed 3016 times

insert2.jpg (3.13 MiB) Viewed 3016 times

I think the keycap is okay, but here are a few pictures of what they look like:

lshift1.jpg (3.22 MiB) Viewed 3016 times

lshift2.jpg (3.24 MiB) Viewed 3016 times

I've tried pulling out and and putting back the keys a lot of times so I'm not sure if that could solve this problem at this point. I'll try to replace the keycaps and post an update if I can solve this issue! I still have no clue what is causing this issue; I'm not sure if it is the foam change or just mistakes in assembly that is causing this.

Thanks for a lot of help

[Weezer]

Sorry that you werent able to get that to work. One last piece of advice is to open it up and swap the spring from the left shift to a 1u key. I recommend trying this first because it will potentially save you the money on new key caps if its the spring thats the problem or if theres a mistake with the assembly of the keyboard.

Other than that, good luck and I hope you end up getting a lot of enjoyment out of your keyboard!