I visited Unicomp a couple days ago, typed on their new Mini M, and asked them some community questions. *long*

[TicTocTom]

I've seen a few that have that on the numpad enter key
I assume they are in an environment where there additional abrasives present that cause additional wear to the keys

I've read that nail polish will do that. Or maybe it's just long nails?

[Darkshado]

To make white on black caps, I think lot_lizard's dye + laser technique looked very promising. See the photo from this 2016 post: viewtopic.php?p=341414#p341414

"Reverse" dye sub could also yield good results, judging by these samples matt3o showed us in 2018: viewtopic.php?p=418330#p418330

[Hypersphere]

@funkmon: Thanks for writing up your Unicomp adventure. Many of us have been curious about the place. It was reminiscent of a Twilight Zone epidode. Interesting, although depressing here and there.

[funkmon]

While they could reverse dyesub to get woblegends I suspect it would be more trouble than it is worth for unicomp. Would love to see it someday

I asked about that, actually. The answer was basically that it was more trouble than it was worth. Troy suggested dying them ourselves and selling them all aftermarket and shit.

That things looks sexy!

However!

Can you fix that bottom (bin off the right windows key and put a full sized space on)! Its making me feel a little sick

Yes, see the first photo with black keycaps.

I saw that ! Very sexy!

If only unicomp did black caps !

Hint: those are Unicomp keys. :3

[gianni]

Maybe next time someone should ask them about spring customization. Making them a little less pingy, and more silent overall. Plus lighter like a model f. That would a really easy improvement.

[kmnov2017]

Maybe next time someone should ask them about spring customization. Making them a little less pingy, and more silent overall. Plus lighter like a model f. That would a really easy improvement.

the springs are not what cause the lightness on model Fs. In fact you can interchange the M springs with Fs and wouldn't notice much different. The "weight" on the Model M comes from the fact that the pivot plates are pressing against layers of membrane to close the circuit....

[gianni]

Maybe next time someone should ask them about spring customization. Making them a little less pingy, and more silent overall. Plus lighter like a model f. That would a really easy improvement.

the springs are not what cause the lightness on model Fs. In fact you can interchange the M springs with Fs and wouldn't notice much different. The "weight" on the Model M comes from the fact that the pivot plates are pressing against layers of membrane to close the circuit....

Pardon my ignorance, but aren't the model f and m identical in the fact that the pivot plates are pressing against a membrane to close the circuit? The pivots are different between the f and the m, anyway this has nothing to do with the fact the the f is lighter that the m, and that more silent and less pingy and lighter spring surely interests many keyboard lovers.

[Hypersphere]

Model M = membrane buckling spring.
Model F = capacitive buckling spring.

Although both Model M and Model F switches use a buckling spring, the model F switching mechanism is based on capacitance sensing. The switch does not close a circuit like the mechanism in, say, a Cherry mx switch.

There is a good discussion of the difference between Model M and Model F switches in the DT wiki:

wiki/IBM_buckling_spring

[kmnov2017]

Maybe next time someone should ask them about spring customization. Making them a little less pingy, and more silent overall. Plus lighter like a model f. That would a really easy improvement.

the springs are not what cause the lightness on model Fs. In fact you can interchange the M springs with Fs and wouldn't notice much different. The "weight" on the Model M comes from the fact that the pivot plates are pressing against layers of membrane to close the circuit....

...The pivots are different between the f and the m, anyway this has nothing to do with the fact the the f is lighter that the m,...

This is EXACTLY the reason why they feel different. As I said, If you put a model F spring in an Model M, it will feel heavier like the original Model M and vice versa...

[gianni]

the springs are not what cause the lightness on model Fs. In fact you can interchange the M springs with Fs and wouldn't notice much different. The "weight" on the Model M comes from the fact that the pivot plates are pressing against layers of membrane to close the circuit....

...The pivots are different between the f and the m, anyway this has nothing to do with the fact the the f is lighter that the m,...

This is EXACTLY the reason why they feel different. As I said, If you put a model F spring in an Model M, it will feel heavier like the original Model M and vice versa...

Considered that I asked "Maybe next time someone should ask them about spring customization. Making them a little less pingy, and more silent overall. Plus lighter like a model f. That would a really easy improvement." don't you think that a lighter and different spring could anyway make the model m switch lighter, less pingy and more silent? That's the point.

[kmnov2017]

Question is, would it buckle then ?

[gianni]

Question is, would it buckle then ?

It's like talking to a crazy man.

[kmnov2017]

???

[kmnov2017]

Question is, would it buckle then ?

It's like talking to a crazy man.

What !!!!

[Hypersphere]

Going to see if I can get a heavier feel in my F62 by installing some of these:

spring.jpg (94.35 KiB) Viewed 7356 times

[kmnov2017]

Good luck trying to buckle that....

[gianni]

Lol. People don't care about what you say. They just have to prove a point. This is a sad sad scene.

[stormcrash]

While they could reverse dyesub to get woblegends I suspect it would be more trouble than it is worth for unicomp. Would love to see it someday

I asked about that, actually. The answer was basically that it was more trouble than it was worth. Troy suggested dying them ourselves and selling them all aftermarket and shit.

Yes, see the first photo with black keycaps.

I saw that ! Very sexy!

If only unicomp did black caps !

Hint: those are Unicomp keys. :3

Ooh that's interesting, tell me more. Did you buy blank black keycaps and find someplace to silkscreen/pad print them?

[Hypersphere]

How about doubleshot PBT to get white legends on black keys? Possibly this could be done with the top piece of two-piece keys, but even so, tooling up for it would no doubt be cost-prohibitive.

[rgleas]

Nice thread, very cool to know they're going to pump out some SSK's

[JBert]

...The pivots are different between the f and the m, anyway this has nothing to do with the fact the the f is lighter that the m,...

This is EXACTLY the reason why they feel different. As I said, If you put a model F spring in an Model M, it will feel heavier like the original Model M and vice versa...

Considered that I asked "Maybe next time someone should ask them about spring customization. Making them a little less pingy, and more silent overall. Plus lighter like a model f. That would a really easy improvement." don't you think that a lighter and different spring could anyway make the model m switch lighter, less pingy and more silent? That's the point.

Woah there. The short answer is "it won't work".

The longer answer is "it depends". IBM chose a membrane contact-based technology as a cost-cutting measure. This choice defines everything else. Lighter springs will put less downforce on the flipper and as a result you will get unreliable
key presses or even repeated presses due to the membrane bouncing up and down until things settle. You could argue that you can hand-pick springs until things work , but a commercial outfit like Unicomp would never be able to spend time on this. And last but not least, springs tend to go soft as they age so frequent use might mean that you get more trouble.

Finally about that noise: it's a buckling spring keyboard and will remain one. Switching springs will likely not change much.

[zrrion]

the only reason it takes more force to press the membrane is because of the rubber mat that is above the membrane, removing that removes a lot of the resistance that the flipper has to overcome to push through to press the membranes together. I haven't done any tests with transplanting F springs into an M without a mat so it is possible that they are too light even for the bare membrane, but membrane switches are not all that heavy by themselves so I'm pretty sure they will work.

As for M springs feeling lighter in an F that is simply untrue. The M spring is just as heavy on an M flipper and an F flipper and the F spring is lighter regardless of the flipper. If you take a look at the M spring it has fewer windings and that is where the additional weight comes from, not from anything else.

[gianni]

Ellipse has tested about 50 different springs before finding the one that sounded like a model f. This means that there is a great variability. Surely unicomp won't test it for us, so we're probably out of luck.

[gianni]

It's quite common knowledge that model f actuation is lighter. Someone says that it's about 10 g lighter. I don't know if it influenced by the spring, or if the pivot - leverage of the pivoting hammer, or by the order of the PCB/ membrane layers.

https://geekhack.org/index.php?topic=58092.0

[Hypersphere]

Here are the closest quantitative comparisons I could find between Model M and Model F switches with respect to peak actuation force and total energy (area under the force-displacement curve). These were each measured by HaaTa:

IBM_M.png (58.14 KiB) Viewed 6969 times

IBM_FAT.png (57.24 KiB) Viewed 6969 times

According to these measurements, the peak actuation force for the Model F (measured on an F-AT keyboard) is about 75gf and the total energy is 236gfmm, whereas the peak actuation force for the Model M is about 70gf and the total energy is about 209gfmm.

Of course, each of these measurements is only an "n" of one (1), so that no statistical inferences can be drawn. However, if these curves should turn out in further measurements to be representative of the two switch types, I suppose it is possible that there are subjective factors about each switch that might give the impression that Model F switches are lighter than Model M switches. For example, these curves apparently do not reveal the relative "scratchiness" of the switches.

[gianni]

So these graphs show that the model f is lighter.

Having used cherry switches for a long time, I feel that the "initial" force, the one that makes the switch move in the first steps, is quite important, probably more than the actuation force. In this case you see that the model f is about 10 grams lighter. The same happens with reds, and silent reds. With the same spring, the normal red is lighter in the first microsteps of the movement, and this makes a big difference.

I've found that many haata graphs are wrong, but he refused to retest them. Not because of laziness, but because he didn't have more switches to test.

Hypersphere wrote that

I haven't weighed the hammer-spring assemblies or the hammers or springs separately, but these bits seem quite light even if the Model F flippers are larger than those on the M. The F switches are lighter -- requiring less actuation force (60-65g vs 65-70g for the M switch). The key travel on the F also feels shorter than on the M, but I do not have data on key displacements. The F feels more precise with a sharp metallic click; the M feels raspy with more of a plastic on plastic sound.

[Hypersphere]

@gianni: I definitely agree with your qualitative assessment of the sound and feel of Model F vs. Model M switches: "The F feels more precise with a sharp metallic click; the M feels raspy with more of a plastic on plastic sound." This is exactly how I would sum up my impressions of the two switch types.

[fohat]

The key travel on the F also feels shorter than on the M,

Doesn't the graph show that the stroke of the Model F is almost a full mm LONGER than the Model M stroke?

[gianni]

Obviously, hypersphere you agree because that's what you wrote some time ago I found it by chance. I just made the quote more clear

[hellothere]

The key travel on the F also feels shorter than on the M,

Doesn't the graph show that the stroke of the Model F is almost a full mm LONGER than the Model M stroke?

The Model F spring is slightly longer than a Model M spring; I'm too lazy to find the thread right now (fohat may have been the poster). I don't have anything to measure that small difference, but it's a visible difference. It's also possible that the Model F foam is a different thickness: I was recommended to get 2mm art foam. It's about 1mm too thick for my '83 Model F.

Regarding the pingy, didn't IBM have a Model M that had "greased" springs or something like that to make them more quiet? IIRC, they were called "Quiet Touch" or something like that. And, no, I'm not thinking of the rubber dome models .