deskthority

At the risk of being accused of sacrilege, I would like to open a discussion of various modifications of the IBM Model F 62 "Kishsaver". Some of the ideas should be applicable to others in this family, such as the F 107, F 77, and even the F 50.

Regarding the F 62 Kishsaver, with the stock plate and case, the keyboard is larger than an RF 87u. However, it seems possible without too much modification to cut down the width to something closer to a HHKB Pro 2. Cutting down the height would entail rearranging the controller so that the size of the top bezel could be reduced.

To reduce the width, the idea would be to cut off the "wings" on each side of the plate, which would result in a plate assembly similar to that of the IBM XT. Then, rather than mounting the plates in the original case, something like an XT case would need to be built, in which the plate assembly would be "dropped in" and secured with a back plate to the case, similar to the way an XT is buttoned up.

This is admittedly rather radical, and runs the risk of deleting part of the intrinsic character of the F 62, which is the considerable heft of its stock case. However, much of the character derives from the plate design and the capacitive buckling spring switches. On the other hand, the proposed mod is irreversible, and considering the rarity of the F 62, such a thing should not be undertaken lightly or without an excellent plan ensuring that everything would work properly and in an aesthetically pleasing manner.

Far less radical a mod is to install a panel-mount USB connector (micro-USB or otherwise) in order to have a detachable USB cable. I am considering various designs for this, which would result only in minimal changes to the stock case.

Sacrilege!



USB socket is fine though, if done elegantly.

https://www.youtube.com/watch?v=--vS3Fy3TjI

dont do it !!!!

I wouldn't recommend cutting up any original F107 / 77 / 62 / 50 myself.

I would recommend trying to get a custom 'XTant' plates and PCBs drawn up, so that we can start building custom Model Fs in whatever layout one desires.

So I feared -- bringing down the wrath of the gods and arousing the ire of my fellow man! Nevertheless, having had the idea cross my fevered brain, I thought it best to purge the thought by bringing it out into the open.

Well, then, perhaps the way to go with this idea is to enlist the aid of wcass (and/or all interested parties) and build a happy hacking kishsaver more or less from scratch. That is, harvest barrels and springs/pivot-plates from the much more plentiful F 122s, make a barrel plate and PCB, equip with a Xwhatsit controller, add keycaps, and serve.

And yet, who knows what evil lurks in the hearts of men? I suppose there are others who have dared to have similar thoughts....

Burn the heretic. Kill the mutant. Purge the unclean.

0100010 wrote: ↑I wouldn't recommend cutting up any original F107 / 77 / 62 / 50 myself.

I would recommend trying to get a custom 'XTant' plates and PCBs drawn up, so that we can start building custom Model Fs in whatever layout one desires.

Yes, this is wise counsel. Especially now that the world's supply of F 62s has been greatly diminished by being absorbed into the red dust of Texas. It seems relatively straightforward to draw up plans for custom barrel plates, but I am less clear about how to draw up plans for PCBs, and I do not know how to go about having such plans converted into actual products.

The idea is to team up and do this all together. Hacking one keyboard is nowhere near as good as creating them anew, as a team.

There are also those Model F boards that nobody really wants to use any more, like bigfoot and blueswitch. I see no good reason to use a kishsaver as a base for a custom Model F.

Muirium wrote: ↑The idea is to team up and do this all together. Hacking one keyboard is nowhere near as good as creating them anew, as a team.

This is great. I sometimes use the same technique at work -- suggest a patently outrageous idea in order to stir up discussion and stimulate collaborations for worthwhile projects! In actual fact, I am quite intimidated by the thought of drilling small holes in the back of an F 62 case to accommodate a panel-mounted USB connector! But the idea of contributing to the design and ultimate construction of a de novo compact capacitive buckling spring keyboard is an intriguing and agreeable challenge.

Seriously, don’t hack these up, it’s a bunch of trouble and expense just to destroy a rare and wonderful thing. If you want to make custom model Fs, get an XT and pull out all the barrels and hammers, and get a custom plate/pcb made. It’ll still end up cheaper and easier than anything you could do to a 4704.

I would be happy to work with anyone to make more F goodness. I like PCB design, case design, and working as part of a team. I hate selling stuff (that includes running a group buy - which i am dreading) so i would happily leave that to someone else. I've already done some work on a 60% (Kishsaver with HHKB style right shift) and 65% with "erase-eaze" split space bar and dedicated navigation.

Two issues with the F are controller complexity and that you can't run the signal lines wherever you like. There will need to be about 12mm border on the sides. An option might be M style with diodes (ala membrane replacement) which would allow for simpler controller and trace routing. I could design either way.

I have a Model M unsaver SSK with 2 rows F keys missing most of the caps that I will mail for free in the US, if that would help? It is rubber dome.

Ok this maybe stupid question but why do we need to run traces around edges? can't we use lets say matrix from model m?
Also Wcass could you send me kicad footpints for switches id like to help with pcb designs.

wcass wrote: ↑I would be happy to work with anyone to make more F goodness. I like PCB design, case design, and working as part of a team. I hate selling stuff (that includes running a group buy - which i am dreading) so i would happily leave that to someone else. I've already done some work on a 60% (Kishsaver with HHKB style right shift) and 65% with "erase-eaze" split space bar and dedicated navigation.

Two issues with the F are controller complexity and that you can't run the signal lines wherever you like. There will need to be about 12mm border on the sides. An option might be M style with diodes (ala membrane replacement) which would allow for simpler controller and trace routing. I could design either way.

Thanks for your pledge of support, wcass! As soon as I get reasonably caught up with work on my day job, I will send and post some rough drafts of proposed plate layouts.

skrsh3r wrote: ↑Ok this maybe stupid question but why do we need to run traces around edges? can't we use lets say matrix from model m?
Also Wcass could you send me kicad footpints for switches id like to help with pcb designs.

Its to to with the capacitative nature of the switch and all sorts of complex electronics stuff that i am not qualified to go into as i will prob get it wrong but usually large areas around the edge of a PCB are for a ground plane or some RF voodoo

if a model f is not grounded correctly you can get all sorts of fascinating malfunctions

Yup. Capsense can have a mind of its own. But this is DT, and Model F is closer to our hearts than humble Model M!

The layout I'd like most to try is essentially HHKB. Sounds like you've got something like that in the works already, Wcass. Excellent!

I'd also be seriously tempted by a HHKB-style Model F. Hardly original thoughts around here, but the HHKB is the perfect layout for me and capacitive bs is my favouirite switch!

We'd need to fit it out in Unicomp caps, of course. So the space bar must be something they carry. Fortunately, the HHKB's vital short right Shift is easily done, with a stepped Caps Lock topped off with the appropriate label.

I also like a few more mods than the HHKB, for the full rectangular 60% look. Something like my HHKB/Poker hybrid 60% comes to mind. Or a version with 1.5u mods and whatever it takes for a perfect fit with Unicomp.



A programmable controller as standard (and an excellent one, in the case of Xwhatsit) makes extra mods powerful stuff. And it saves us the bother of a case with blanking at the sides.

less mods more spacebar !

andrewjoy wrote: ↑less mods more spacebars!

Sure! If you like it that way.

If you ask me Id like to try fiting custom pcb in existing model m cases first.

Another vote here for a HHKB Pro 2 layout, or something very close to it. For me, the existing HHKB Pro 2 layout is perfect!

If I were to go with anything larger than a 60% HHKB Pro 2 layout, it would be TKL or a modified TKL w/o F-keys.

A layout like this would appeal to me, it's very symmetrical and should be doable with Unicomp keycaps. Go, SPH international kit, make it to MOQ!

Nuum wrote: ↑A layout like this would appeal to me, it's very symmetrical and should be doable with Unicomp keycaps.

Spoiler:

SPH custom.PNG

Go, SPH international kit, make it to MOQ!

I do like the idea of a short space bar (or two of them), but I have never been able to appreciate layouts that fall into the twilight zone between 60% and 80% (TKL). But this is why we do what we do to make personalized layouts.

Doable besides the all doubleshot legends!

2.25u mini spacebars are a nice idea, especially with the no-wire stab system they use. But they wouldn't be round profile. (Checks IBMs…) The difference isn't as pronounced on IBM/Unicomp caps as on SA, but a repurposed Shift cap still wouldn't make an ideal spacebar. The Shift keys bulge upwards at either end. Spacebar is more uniform, with a smooth lip all the length of the front for your thumb. It does feel nicer to press than any of the mods, forgiving its wire stab.

Code key from wheelwriters can be nice for split space bars

Besides the right shift, this layout would work on Kishsaver.



Or it could work with a custom plate / PCB. Or remove the bottom outer edge modifiers and you have HHKB.

EDIT : You can't see it in this image, but that number row also has front function legends printed.

Also i forgot to ask but do you have model m membrane drawings?

There is an SSK membrane PDF in this thread on GH : https://geekhack.org/index.php?topic=59027.0

But - we are talking capacitive PCBs in this thread, Model Fs.