Model M Cushionless Mod

User avatar
Bitteneite

24 Aug 2021, 21:29

The following mod was discovered by Pandrew. Full credits to him for shedding light on this mod and sharing it!
I wouldn’t be surprised if this was discussed here before, but I haven’t seen it mentioned anywhere outside of the r/ModelM Discord server, so here’s a guide for awareness!

In your average everyday Model M, the plastic flippers have a slope, or a "cushion" if you will.

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As you bottom out, this cushion squeezes the stem of your keycaps inwards, or "forks" if you will. As a result, you get a softer bottom-out feel. This flex remains present even after a bolt/screwmod!

Notice how the forks squeeze inwards!
(Video by Pandrew)
Finally! All the dark mysteries of the Model M bottom-out flex... Out in the flesh!

Honestly, I was just as surprised myself about this, as I've never realized that our Model Ms were originally, albeit indirectly, dampened! (Gasping Intensifies)

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Model Fs don't have the "cushion" on their flippers. Perhaps this is why they feel sharper when bottoming-out?
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Pandrew perfectly demonstrates this in action. You can see how much more the key can travel without that cushion!
(Video by Pandrew)

Good news for our Ms: Some early Wheelwriters came without the cushion, which can feel awesome when put in a regular Model M! :D
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(Photo by Fricked)

Unfortunately, not everyone has access nor luck to stumble across a Wheelwriter, let alone one with cushionless flippers.
So... why don't we make our own?

Pliers Method

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(Photo by Pandrew)

It's as straightforward as it gets.
It gets the job done quickly, but it's not exactly pretty. :|
The biggest downside here is just how easy it is to crack the whole flipper. You need to be extra careful here. For best results and minimum cracks, you’ll want your pliers to be thin, sharp, and short.

Image
(Photo by Pandrew)

This method is already pretty ghetto, and if you snip it too deep, you will get these ugly cracks running down the flipper. :?

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(Photo by Pandrew)

It’s not the end of the world, your flipper would still feel fine.
I compared a slightly cracked flipper to a cleanly-cut flipper in a Model M, and I honestly wasn’t able to notice any difference.
However, if you cut any deeper, it’s definitely game over.

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If you're lazy, then I'd recommend you only do this to your alphabetical keys and spacebar.
(Skip the numpad, arrow keys, F-row, number-row, hell... skip even the mod keys!)

Self-plug: If you were to restore a Model M in the process, I have a handy megaguide that you might find useful!

Note
I hope we can get more people to chime in to give better, less jank techniques for doing this mod.
  • Pandrew originally used a Dremel, but he had troubles holding the flipper in place.
  • Pandrew suggested a rig for the Dremel method for an idea.
  • Even when I was confident with the plier method, I was still cracking about 2 flippers every 10 flippers. This could’ve been less if I had better pliers, but it’s still inevitable that you too will crack a handful of flippers.
  • Pandrew also tried heating up his pliers for a cleaner cut, but it didn’t do much.
  • Pandrew suggested to Dremel out his pliers to act like razor-sharp scissors. It probably won’t cut metal anymore, but it could be a useful specialized tool for this mod.

End Result
So, how does it feel in practice? Well, after dailying one for about a week, it's... awesomely subtle! You receive a slight increase in key travel, and a great reduction in bottom-out flex!
The added travel feels more natural in your hands, and when it's combined with a solid bottom-out feel, your M suddenly springs to life! Again, it's pretty subtle, but at speed, your Model M feels noticeably more satisfying.

Don't get me wrong, your M won't transform into an F. It's still missing that "dense" plate feeling, but right now, there’s less of that “short-travel” feeling, and the majority of that bottom-out flex is outright gone! 8-)

Sound-wise, it got a lot louder in a "clacky" way.
Unfortunately, this meant that all the "thocc" had poofed away. (r/mk would not be proud)
If you like the sound of an F, you probably won’t mind the cushionless sound.
Again, sound is just preference, but personally, I prefered the stock bassy sound.
In my opinion, the improved keyfeel far outweighs the loss of the thocky sound.

Is it worth the effort?
Probably, but only if you have some spare flippers around, as it's surprisingly easy to break them with the pliers method.
Stock up on some Unicomp flippers, just in case ;)
Your M will feel more lively, and considerably more fun to type on!

That being said, it still feels distinctly like a Model M. Expect a subtle upgrade, not a “transformation”.

Credits to Pandrew for discovering this mod!

User avatar
NeK

25 Aug 2021, 06:47

Wow. Nice!

Does it change the apparent weight too? Does it make them lighter? If so how do they compare to an F?

I am tempted to try this.

User avatar
Bitteneite

25 Aug 2021, 07:17

NeK wrote:
25 Aug 2021, 06:47
Wow. Nice!

Does it change the apparent weight too? Does it make them lighter? If so how do they compare to an F?

I am tempted to try this.
Unfortunately not. The weighting remains the same.

Again, the only thing changing here is the bottom-out feel, which becomes quite similar to an F! :D
(Not completely, but it's a step in that direction)

User avatar
Palatino

25 Aug 2021, 07:30

Ah, so that's why one of my Wheelwriters feels so good! I half-thought it had Model F switches in its keyboard somehow. I've never opened it up, but it must be cushionless flippers. The difference is appreciable!

pandrew

25 Aug 2021, 10:06

@Palatino
You should be able to see if it's cushionless just by taking off a single keycap and shining a light through the barrel. If it is indeed using cushionless flippers, could you post any info you have on it? E.g. if you know date / location of manufacture, or model number?

@Bitteneite
Thanks for documenting this! I was too lazy, and you did a better job documenting it, than I would have. I especially enjoy the quality of your illustrations.

User avatar
Karmel

25 Aug 2021, 16:08

Bitteneite wrote:
24 Aug 2021, 21:29
That being said, it still feels distinctly like a Model M. Expect a subtle upgrade, not a “transformation”.
I've never done this with a regular M, in fact this is my first time hearing about people modding cushioned M flippers like this. But I will say that my Wheelwriter 5 which has the cushionless flippers feels pretty much identical to an F, except for in sound. Although that's only if I have original Model F or Unicomp caps on it, otherwise it's intensely scratchy.
Last edited by Karmel on 25 Aug 2021, 16:12, edited 1 time in total.

User avatar
Karmel

25 Aug 2021, 16:11

Palatino wrote:
25 Aug 2021, 07:30
Ah, so that's why one of my Wheelwriters feels so good! I half-thought it had Model F switches in its keyboard somehow. I've never opened it up, but it must be cushionless flippers. The difference is appreciable!
You can see what flippers it has just from looking into the barrel. Only very early Wheelwriters had cushionless flippers, any from after the enhanced keyboard came out have regular flippers and feel identical to a regular M.

User avatar
Palatino

25 Aug 2021, 16:33

Ok, I'll take a look when I'm home. For sure I have a Wheelwriter that feels different from a regular M, from memory at least. I'll grab a torch, do some side-by-side typing and report back. One thing is certain, though: I have too many typewriters.

User avatar
Bitteneite

25 Aug 2021, 16:47

Karmel wrote:
25 Aug 2021, 16:08
Bitteneite wrote:
24 Aug 2021, 21:29
That being said, it still feels distinctly like a Model M. Expect a subtle upgrade, not a “transformation”.
But I will say that my Wheelwriter 5 which has the cushionless flippers feels pretty much identical to an F, except for in sound.
Oh damn, Interesting.
I just tried some F caps on my M, but it was only marginally smoother. That being said, I do hear people confirming, in general, that one-piece caps feel much smoother.
I also might've felt a less cushioned bottom-out, but that easily could've been placebo. Can someone confirm?

There was still a noticeable difference in weighting. I didn't feel the M feeling any lighter, but again, it could just be me. Can someone also confirm?

User avatar
Wazrach

25 Aug 2021, 17:41

Bitteneite wrote:
25 Aug 2021, 16:47
Oh damn, Interesting.
I just tried some F caps on my M, but it was only marginally smoother. That being said, I do hear people confirming, in general, that one-piece caps feel much smoother.
I also might've felt a less cushioned bottom-out, but that easily could've been placebo. Can someone confirm?
I imagine the two-piece caps are quieter as they are thicker, which might give the impression of being more cushioned. It's a bit like Unicomp caps on an F feel quite harsh and rattly.

User avatar
Karmel

26 Aug 2021, 03:25

Bitteneite wrote:
25 Aug 2021, 16:47
Oh damn, Interesting.
I just tried some F caps on my M, but it was only marginally smoother. That being said, I do hear people confirming, in general, that one-piece caps feel much smoother.
I also might've felt a less cushioned bottom-out, but that easily could've been placebo. Can someone confirm?

There was still a noticeable difference in weighting. I didn't feel the M feeling any lighter, but again, it could just be me. Can someone also confirm?
I heavily depends, 1 part caps do feel smoother from my experience, but not equally. In terms of smoothness from the caps that I have tried, I would place them in order of Unicomp 2 parts < 2 parts from Ms < 1 parts from Ms (this one can vary a lot though) < 1 parts from Unicomp (Can be inconsistent in quality to the point of not working and being useless, same can apply to 2 parts.) < 1 parts from Fs (some Fs can have scratchier caps but they are mostly smooth).

In terms of the bottom out feel and sound, it's all over the place, I have 2 part caps that bottom out harder than 1 parts and 1 parts that bottom out harder than other 1 parts. Generally F 1 parts and Unicomps in general have a louder and harder bottom out. Also if the caps are in an F they will always have a harder bottom out than if they are in Ms unless the flippers are cushoinless.

User avatar
Bitteneite

26 Aug 2021, 17:25

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I read up on an interesting measurement Pandrew posted on the Discord server. He used a "package weighing hook" through his keytester to see just how much force it took to bottom out. He compared an original IBM keycap with a Unicomp keycap. (Of course with a cushioned flipper)

After verifying his numbers, his measurements came out as 1000g for the original IBM keycaps, and 2300g for the Unicomp keys with shorter forks. The cushion mechanism was obviously still present, but the shorter forks made the cushion much stiffer.
Interesting find...

User avatar
raoulduke-esq

26 Aug 2021, 18:32

Ok y'all... what if you dremmel out the fork on your Unicomps to make them deeper like the OG IBMs??

User avatar
Karmel

27 Aug 2021, 02:49

I always noticed that the forks on Unicomp caps were different but I never knew why. The fork probably spreads out once in reaches the bottom because of the slope that the cushion has, this would also explain why the bottom out on Fs and cushionless Ms isn't changed by Unicomp caps.

pandrew

29 Aug 2021, 04:40

I don't think the forks were made shorter specifically to stiffen up the keys at the end of their travel.

Remember, the Model F keys still had the forks. The primary function of the fork, in combination with the little triangle-wings at the end, is to hold the key inside of the barrel, so it doesn't come out too easily, and it's in a position where there is a tiny-tiny bit of pressure on the spring, so the spring is already prepared to buckle in the correct direction. So the little triangles at the end of the keystem are primarily retaining clips. And the forks are not just filled in, cause you want _some_ flexibility, so that you can push in and remove the keys.
When the Model M flippers were designed, the first Model M flippers didn't have a cushion, but then when the cushion was added, they reused the existing shape of the keystems to implement the cushion.

I would bet that Unicomp changed the length of the forks in order to make it less likely that keys would pop out during shipping, and that they didn't care what effect it had on a cushion. For now I'm assuming that it was indeed Unicomp that made this change cause I'm not aware of any IBM keys with shorter forks.

Unicomp in fact made another change, more recently, whereby they made the retaining clips thicker and more rounded, see Sharktastica's New Model M review here:
https://sharktastica.co.uk/articles/newm_review

In particular scroll down to this image:
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On shark's page he describes what keyboard each pictured keycap comes from.

My opinion (and again, this is just pure speculation) is, that Unicomp made the retaining clips thicker for one of two possible reasons:
1) Maybe to make it even more less likely that keys would pop out during transportation. - And this would be quite plausible, cause Unicomp used to ship keyboards with warning notes saying that keys might pop out and its normal, so it would make sense for them to try and improve this issue.
2) Maybe to make keycap yield higher. That is - I can imagine that sometimes during injection molding the retaining clips wouldn't form perfectly, and they would have to throw away those faulty keys that don't pass quality control. But if the clips are thicker, it's less likely that there would be keys that don't pass quality control.

I think the thicker retaining clips will also have a less-noticable effect in combination with the cushion, I think they further reduce keytravel, however I don't currently have any keys with thicker retaining clips, so I can't really test to see if I can feel the difference.

retrofitit

01 Sep 2021, 00:49

I would probably cut the cushions away with a needle file instead of clippers.
True, it would be slower and a bit tedious, but not as slow as waiting for some replacement flippers to be shipped to me.

User avatar
Bitteneite

01 Sep 2021, 16:53

retrofitit wrote: I would probably cut the cushions away with a needle file instead of clippers.
True, it would be slower and a bit tedious, but not as slow as waiting for some replacement flippers to be shipped to me.
That could be a wiser method to this mod. Though, as you said, it takes a bit longer.
If you can do it consistently, definitely post it here with pictures and results. It might be the safer approach we need.

That being said, Pandrew recently sharpened his pliers down with a Dremel, and he came back with some good news!
He also brought a filer into this mod, and honestly, I think I should definitely do that next time. Retrofitit definitely had a point here.

Before:
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(Photo by Pandrew)

After:
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(Photo by Pandrew)

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(Photo by Pandrew)

He reported that he hasn't broken any flippers with it yet with the sharper pliers. He also mentioned how much more precise his cuts were, and so the "crack line" became more predictable.

He also paired up a thin filer to remove the "little whiskers that might remain attached", which is should make for a much cleaner job! Nice work, Pandrew.

Perhaps both approaches could be used for a very consistent result?

User avatar
zrrion

09 Dec 2021, 00:26

Just wanted to chine in on this to say that I have attempted this mod with flippers of my own and the results are quite nice. if done properly removing the cushion from a standard M flipper gets you results identical to that of the WW flippers that don't have a cushion to begin with.

I tried using cutting pliers to remove the cushions but this broke too many flippers so I instead used a hacksaw to cut the flippers. by holding the saw upside down and moving the flipper over the blade you can cut into the flipper in a way that leaves a small tab between the cut and the edge of the flipper which can simply be broken off. I then took a hobby knife and cleaned up the edges of the cut and they work very well.

Here is a typing test of my mod in action compared against my F122: https://v3.fastupload.co/file/10587 The F has individual foam gaskets for each barrel and has a lubed spacebar. The square badge M has WW cushionless flippers on the alpha cluster and modded flippers everywhere else, additionally the M does not have the rubber mat inside the assembly and the space bar has not been lubed. Interestingly the M is louder than the F is and in my estimation the M also pings more. I do plan to loom mod both the M and possibly the F in the future so it will be interesting to see what that does to them.

User avatar
Muirium
µ

09 Dec 2021, 11:36

Interesting wee read, all of this. All new to me.

This is the loom mod Zrrion was on about. A heavier version of the floss mod, in essence. Sounds a bit too stiffening for Model Ms to me, but it's something to try and see.

Might play around with a bunch of this stuff—including maybe the floss mod—if I bother bolt-modding my reserve SSK. Seeing as you need the access, and it needs the fix…

gianni

09 Dec 2021, 13:20

NeK wrote:
25 Aug 2021, 06:47
Wow. Nice!

Does it change the apparent weight too? Does it make them lighter? If so how do they compare to an F?

I am tempted to try this.
You can swap springs to make it lighter that a model F
The results for the spring buckling (i.e. not bottom out) are:
Unicomp Model M with original springs: 66g
Unicomp Model M with New Model F springs: 44g
New Model F with New Model F springs: 53g

viewtopic.php?f=2&t=26604&p=496495#p496495

gianni

09 Dec 2021, 13:20

gianni wrote:
09 Dec 2021, 13:20
NeK wrote:
25 Aug 2021, 06:47
Wow. Nice!

Does it change the apparent weight too? Does it make them lighter? If so how do they compare to an F?

I am tempted to try this.
You can swap springs to make it lighter that a model F
The results for the spring buckling (i.e. not bottom out) are:
Unicomp Model M with original springs: 66g
Unicomp Model M with New Model F springs: 44g
New Model F with New Model F springs: 53g

viewtopic.php?f=2&t=26604&p=496495#p496495

User avatar
zrrion

09 Dec 2021, 18:03

Muirium wrote:
09 Dec 2021, 11:36
This is the loom mod Zrrion was on about. A heavier version of the floss mod, in essence. Sounds a bit too stiffening for Model Ms to me, but it's something to try and see.
I actually intend to cut a small "plug" from the loom bands similar to the foam plug mod. I figure cutting a band will be easier than punching foam plugs. Using the full length would probably be fine on an F due to how light those are to start with but for an M I think that would be too much.

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