Model F hacks

[bladamson]

So yea, as mentioned in a previous thread, I had thought my Model M was worn out beyond repair, so I ordered a rather used F from clickykeyboards, 'cos I've been wanting one for years anyway.  I since managed to fix the M, mostly, but the F has already shipped, so that's a good rationalization for keeping it anyway.


Part 1:

When the thing gets here, in addition to transplanting in the pipe, backspace, and enter from a broken model M donor board, I have been thinking about fiddling with the numpad as well.  It seems like the only time I ever use the numpad is for punching in credit card numbers, which doesn't happen all that often.  So I want to transplant the cursor control keys from the donor M into the F numpad, something like this:



If I do this, I'll either have two dead keys or I'll need to find some springs and rocker thingies somewhere.

Does anyone have a handful of these that they'd be willing to part with, perhaps out of a dead XT donor?

I'd need two, or maybe four if I should decide that I need to move hyper and super down by the spacebar.  Though I seldom have the (dubious) pleasure of having to use Emacs.  


Part 2:

I'll also occasionally want to attach this thing to my laptop, for long hacking sessions away from home.  Remapping the keypad scancodes in the OS on the laptop won't be a huge issue, since the laptop doesn't have a keypad anyway.  And except for the two additional keys, all of the keys will produce standard scancodes anyway, so I can just ignore the relabeled keys if I need to and treat it like a normal keypad if I have to.  However, this isn't the case with the relocated pipe key, since the original pad is covered by the backspace key.  I'm thinking about remapping this one in hardware by cutting a couple of traces on the board and running a couple of jumper wires.  It looks like I can do the front of the board without any of the jumper wires getting in the way of the keyswitches, like so:



Hopefully if it goes wrong, I can just tack across the cut traces with solder and be back to stock.

Does anyone have a decent photo of the back of this board?  I can't see through the board well enough in that picture to tell if the other pad is in the same column or not...

Has anyone ever tried this?

[msiegel]

it's in the same column.

the top row pad to the right (under the original small backspace) is in a column all by itself.

i'll try to get a shot of the back tonight.

this sounds like a cool hack

[bladamson]

i'll try to get a shot of the back tonight.

Thanks!

Since it's a scratch-n-bang model, I'm thinking about dumping the case into black rit dye, too.  From some of the dings in the seller's picture, it kinda looks like the case is painted though? O_o  Not sure how well dye will take to that...  Might do the keys too, iunno...

Where'd you get your hammers and springs for the additional keys?  If you've got a few extras, I'd happily trade you (or anyone else) some M parts or a few bucks.  My donor board is a 1391401, 19AUG88, with a dead column.  It's missing esc, leftarrow, and f10, and I'd like to keep the backspace, pipe, enter, and maybe spacebar for my F.  It seems a shame to spend a bunch on a probably-functional F-XT and then tear it up just for four parts (why on earth do they cost so much?  They won't work on anything newer than 1982. o_O).

[msiegel]

hammers and springs for the additional keys?  If you've got a few extras, I'd happily trade you (or anyone else) some M parts or a few bucks

after counting my parts, i'd be happy to send you a half dozen model F/AT spring/plate assemblies from a board i'm converting

even better if you have a model M Right-Arrow & Ctrl to trade

[bladamson]

after counting my parts, i'd be happy to send you a half dozen model F/AT spring/plate assemblies from a board i'm converting

even better if you have a model M Right-Arrow & Ctrl to trade

Oh sweet.  Very very awesome.

Hmmm, let's see....  I used to have two working Ms and two broken ones, but I seem to have lost two of them last time I moved (and one of the working ones at that. D:= ).

I have two extra control keys, which I can part with no problem.  One is a little shiny and the other one looks fine.

I only have one right arrow, though, on the keyboard I am using, which I was planning on transplanting to the F (if I don't dye all the keys black).  I'm not sure yet if I will dye them or not, kinda depends on the condition of the board.  I mean, I dunno.  If it's sparkly looking with only a ding or two on the case, it'd be a shame to dye all those old keys that are impossible to replace...  Unless I replace them all with dyed M keys and keep the old ones around. :3

I guess if you want the right arrow super-bad and can't find one anywhere else, I don't think I'd cry too hard if I had to let it go.  It's a little shiny though.

Clickykeyboards has one right arrow cap in stock for $1, too.  http://www.clickykeyboards.com/index.cfm/fa/categories.main/parentcat/10191

I have some other stuff for trade too.  Gonna make a new post about that.

I'll send you a PM with my contact info!  Thanks again!

[bladamson]

Happy news:

I found another '91 M while I was digging through my junk!  So yes, I have a right arrow key for you for sure, though it also is a little shiny.

Edit- Grumble, it has nonfunctional ZXC keys.  Maybe I can engineer one working M out of both of those broken ones...

[Soarer]

I don't suppose that means you have a spare space & backspace does it? :-)

[ch_123]

Model Ms are pretty easy to repair. All you need to do is remove all the rivets, use a silver conductive gel pen to fix the traces, and then do the bolt mod described elsewhere on this site.

[bladamson]

I don't suppose that means you have a spare space & backspace does it? :-)

I am not entirely certain yet.  Probably, as I see no need to type on two Ms at once, even if one of these is fixable, and I'm not sure I completely trust the suggested conductive ink fix.

As soon as I get a new nut driver and open it up and verify that it is indeed the keyboard matrix that is causing the trouble, I will know for sure.  The one of these with the whole column flaky may be a cold-solder joint on the controller, or at least I have my fingers crossed for that.  I'd rather not part out one that can be fixed in a robust way.

The Model M that I am typing this on is going to get rit-dyed solid black as soon as I get my F remapped.  When I do that, I'll use an extra keypad 0/insert for backspace and will definitely be able to let go of a backspace cap.

[Soarer]

See how it goes then :-) I hope you get that M working again even if it means I can't have some keys!

If you can get hold of a Teensy, I could send you a hex file to load onto it to make a PS2 to USB adapter that works with all the AT-F codes :-)

[msiegel]

the back side

[bladamson]

Woohoo!  Thanks!

So it's definite that the front is the only part that needs to be hacked then!  Excellent!

Anything else you need besides 1x Ctrl and 1x Right arrow?  Do you need the plungers too, or just the caps?

[Sam]

It seems a shame to spend a bunch on a probably-functional F-XT and then tear it up just for four parts (why on earth do they cost so much?  They won't work on anything newer than 1982. o_O).

They only cost so much if you've overpaid.  There's a constant stream of people who find these and think they're worth a fortune.  They're not. The going price is about $10 + shipping.  Anything much higher than that will in all likelihood go unsold.

[msiegel]

Woohoo!

i do need 4 more of these stabilizer guides (just the white part) for my mod. if you have spares, that would great.



never mind about the Ctrl and Right Arrow, i've decided not to resurrect that other board.

i'll try to get some shots of the extra model f parts i have later tonight

[bladamson]

Groovy.  I pulled 4 white spacers out of the '91, along with a right arrow and right control (it is less worn than the left one).  I have three more white spacers spare and two of the offset blue ones if you need more.

Both keycaps exhibit slight shininess, but you can only see it at a very horizontal angle.  The keycaps are both deloused, but a couple of the spacers may need an itty bitty bit of interior delousing around the top with a pipe cleaner.  I don't really have anything to stick down on there that I'm not afraid will scratch.

Sorry about not having pictures.  I don't own a camera, not even a cell phone camera, as I live way back in the middle of nowhere where there's no cell service.  If you want pictures, I can borrow a camera from a friend, but probably won't be able to until Tuesday-ish.

I'll mail the spacers Tuesday-ish as well.  If you decide that you want those two keycaps after all or anything else before then, let me know.

I'm pretty interested in the shell as well as some spring/hammer assemblies and four of those stem thingies that your spacer is stuck into in that picture, I think.  Possibly any non-M-sized keys that you're disposing of, too, if I decide to do the flat black dyed F thing.  I'll send some money for shipping or whatever, esp if the shipping cost with the shell is nuts.

Thanks again!


Oh yea:  Is there any noticeable difference between the F and M stems?  They're completely interchangeable, right?

[Daniel Beaver]

Oh yea: Is there any noticeable difference between the F and M stems? They're completely interchangeable, right?

Model M stems are all part of an integrated full-board stem assembly, so you can't just swap out stems. Model F's have individual plaster pieces for each stem. The stems themselves are pretty much dimensionally equivalent (the wiki has more info in that regard).

If you want to add keys, you need to find someone who has a junk Model F that you can cannibalize for extra stems and (more critically) hammers. Anything short of that isn't going to work.

[bladamson]

If you want to add keys, you need to find someone who has a junk Model F that you can cannibalize for extra stems and (more critically) hammers. Anything short of that isn't going to work.

By "stems", you're meaning the piece that the spacer guide thingamabob is stuck into in msiegel's picture?

So I need them for the M-spacebar-swap and for adding two keys to the keypad then, but not for the M-backspace-pipe-and-enter-swap, correct?

And the model M keys/plungers/whatever fit into them properly?  Or is there a step in the backspace/enter swap that I'm missing?

Adding four of those to the wishlist in the previous post, then. :3  Hehe.

[bladamson]

Hmm, I had a thought...  (Yes, scary, I know...)

Considering how into fabricating parts you are, msiegel, I wonder how much it would cost to have fabricated, in small quantities, parts that would fit into an M: an F-like front plate, an F-like foam pad, and an F-like capacitive matrix board with (if needed) a teeny bit of logic at the top to convert the capacitance matrix signal levels into something that an M logic board could read.

Then the keyboard hobbyist could buy this kit, perhaps at-cost, along with a couple of XT-Fs for the barrels, springs, and hammers, and bolt the whole deal onto their M backplate, thus producing a keyboard with the superior M layout, superior F keyswitches, and no wonky OS-level keysym remapping required.

Probably too expensive, eh?  Probably cheaper to build a new logic board to put into a 3270 board with swapped out keys, huh? :<

It'd be a pretty sweet keyboard, though......

[bladamson]

Here's a better list of the Model M loot I have for trade.

http://www.adamsoncomputing.com/ModelM_ModelF_Parts_List.html

Soarer, you're welcome to a spacebar and backspace if the shipping costs to where you are aren't too insane.  The spacebar has a little bit of a shiny spot on it though. ;<

[Soarer]

That's great, thanks! I wouldn't mind taking the opportunity to get a couple of other keys, so I'll think about which and send a PM shortly, if that's ok. :-)

[msiegel]

The sun came up! It's time for a survey of the shell

It has tons of scuffs and a little worn paint, some scratches on the underside of the bottom half, bit of sticky gunk, but apparently no chips or dings.

Huh, it's missing a foot.

[msiegel]

I wonder how much it would cost to have fabricated, in small quantities, parts that would fit into an M: an F-like front plate, an F-like foam pad, and an F-like capacitive matrix board with a teeny bit of logic

if all goes well, we'll find out in 2011

although my goal isn't to fit an f into an m, i will be replacing all the electronics and structural components.

current design for colemak layout - you can see why i need extra stabilizer guides

[bladamson]

That is.....  Unspeakably awesome.  Lol.

So you're planning to make an eventual production run of these things, or at least the parts?  Are you going to have the post-prototype barrels and hammers fabbed too, or just reuse XT scraps or something?

Thanks for the enclosure pics!  I sent you a PM.

[msiegel]

for the prototype i'm using barrels and spring/flyplate assemblies from a gutted model f. i'm now developing new sensor electronics.

current plan is to create a flat top plate and backplate in wood, with aluminum foil for electrical shielding. since adjacent barrels don't have space between them, they may keep *themselves* aligned, without a need for extreme precision in the top plate.

overall my goal is to develop a working prototype i can use and enjoy, and to share design specs for others to fabricate their own versions -- or send away for cnc fab in different materials.

i'd love to have cad models and specs for brand new springs and injection-molded barrels & flyplates, but i don't know anyone who wants to do it, open source and for free

[Soarer]

Tin foil hats and self-aligning barrels? Sweet!

I suspect the barrels won't play nice. They have a nub for alignment. Maybe if you made a slot for that to fit in, and used some hot glue to set them straight, you could avoid precision machining...? [ Just thinking out loud :-) ].

[Daniel Beaver]

By "stems", you're meaning the piece that the spacer guide thingamabob is stuck into in msiegel's picture?

Yes. You can only get them out of Model Fs.

So I need them for the M-spacebar-swap and for adding two keys to the keypad then, but not for the M-backspace-pipe-and-enter-swap, correct?

Yes. The big backspace mod only requires spacers and keys. The spacebar/alt swap requires three extra of those stem pieces, as well as three hammers.

And the model M keys/plungers/whatever fit into them properly?  Or is there a step in the backspace/enter swap that I'm missing?

Adding four of those to the wishlist in the previous post, then. :3  Hehe.

Yes, Model M keys should work.

I have extra Model F hammers and stems in storage if you really needed them. I am, however, currently living about 1500 miles away from them, and I would rather not have to call up a friend to drive out and rummage around for them, ship it to me, etc. Hopefully someone else on the board can help you out in that regard.

[msiegel]

i'll be shipping model f parts out to bladamson next week

[bladamson]

I have extra Model F hammers and stems in storage if you really needed them. I am, however, currently living about 1500 miles away from them, and I would rather not have to call up a friend to drive out and rummage around for them, ship it to me, etc. Hopefully someone else on the board can help you out in that regard.

Thanks for the offer, but yea, M. is sending me a pile of stuff after Christmas. ^_^

[Sam]

if all goes well, we'll find out in 2011

although my goal isn't to fit an f into an m, i will be replacing all the electronics and structural components.

current design for colemak layout - you can see why i need extra stabilizer guides

Show Image

Nice job on the staggering.  What's that green dot for?  A trackpoint?  Best of luck on your project, I'll be very interested to see how it turns out.

[msiegel]

thank you

that's an led. i did leave space in the middle of the home row for something, but i haven't decided if anything will go there yet

[bladamson]

Hm!  I just got bored and read up on Colemak.  Pretty cool.  I think I'm gonna make my //e platinum keyboard into a colemak. :3

In other news, there's too much snow here for me to get my motorcycle to the paved road, so shipping of your model M parts may be delayed until Tuesday or Wednesday, at which time the weather report is calling for temperatures that should be high enough to unmelt the roads, and I'll be able to make it into town to the post office.  I'm sorry. :<

[msiegel]

no hurry. i have circuitry to design... and not being an EE, this is a very slow process

[bladamson]

i have circuitry to design... and not being an EE, this is a very slow process

I hear ya there. X_x

[bladamson]

How's your research into capacitive switches going?

I'm looking at teensy boards, thinking about slotting one into the F/PC, and wondering what the easiest way to convert capacitance changes into TTL levels is. :3

[bladamson]

Hmmmm

http://sensi.org/~svo/capsensor/index.en.html

[bladamson]

Looks like he's using the AVR's ADC for that one though.  You'd think that you could like...  Use a TTL buffer or something with just the right value resistors to make the output flop between 0 and 1 when the key was pressed...  I guess that would probably end up being temperature sensitive though, wouldn't it? :s

I don't really know what I'm talking about. >_>

Looks like it would indeed be easier to just decode XT scancodes in software hahaha.

[msiegel]

Spoiler Alert

don't tell Sam this approach, he's working on his own version and doesn't want to be tainted...

i've been slowly building a test circuit in LTSpice simulator, based on insights gleaned from the original patent docs. once the model is working i'll prototype it on a breadboard using the existing model f "switch" pcb (minus the microcontroller card).

the circuit sends a 0.2us five volt pulse through one of the pads and sees if the pulse travels through the pad on the back side. if the flyplate (aka hammer) is close to the pads, the signal will couple all the way through.

i considered using the avr's onboard adc or comparator to do the detection, but it's way too slow! so i'm using an external comparator chip. come to think of it, that external comparator is sensitive enough that i might be able to ditch some of the other components... thanks for the idea

i don't quite have the simulated circuit working yet -- still figuring out how to use hysteresis for the comparator, but it shouldn't be too much longer.

[msiegel]

Looks like he's using the AVR's ADC for that one though.  You'd think that you could like...  Use a TTL buffer or something with just the right value resistors to make the output flop between 0 and 1 when the key was pressed...  I guess that would probably end up being temperature sensitive though, wouldn't it? :s

I don't really know what I'm talking about. >_>

Looks like it would indeed be easier to just decode XT scancodes in software hahaha.

i like your idea... i don't have any of those parts handy, but maybe a 555 could be rigged up to test, once i try this other way

/not an ee

[msiegel]

loot4bladamson



there are some extra dampened cream alps in there... i may have killed 1 or 2 of the oranges

[bladamson]

Zomgwow.

That's a lot of lewt. XD

Do you really wanna get rid of all that stuff? :3

Awesome. :3  That mac keyboard is going to rawk. :3

[bladamson]

Left: Model F/PC
Right: Model F/AT
 

Result: Very very slight difference in shape at the hinge, but identical curvature.  They both work fine in either type of barrel.

[bladamson]

Left: Model F/PC
Right: Model F/AT

   

Result: They are functionally identical except for the little post that keeps them from rotating.  They could be interchanged if (1) the post was cut off, which might lead to key instability, or (2) the faceplate drilled to accommodate the differently placed post.

In practice, the foam would probably do an excellent job of keeping them from moving once the board was reassembled, and cutting the post would probably be just fine.

Also, the foam in the F/PC board is of much much higher quality than that in the F/AT.  The PC foam looks and feels new, whilst the AT foam is starting to degrade from age.

The boards have a very slightly different feel.  The PC board is stiffer and pingier.  The AT board is also very pingy, but not quite as much.  The force of actuation between the two seems about the same, but the AT seems to have a sharper force-curve leading up to actuation, ie the PC is relatively stiff throughout key travel, whereas the AT is less stiff leading up to the point of actuation.  This may just be an artifact of spring age and wear.

I prefer the feel of the AT.

[bladamson]

Getting ready to cut it up...



Mod complete.



Jumpers.  Pipe is moved down onto the pad underneath of backspace.  The wire on the right jumps the numpad back to the uC (see A).  Wire is stolen from an old PATA cable, so the insulation melts really easily when being soldered. -_-'



(A) The trace that was cut for the remap also needed to run to the numpad, so it's jumped back here to the uC.



This trace was cut, so we have to run a jumper to the other side for the numpad. (see A)



Jumper for the numpad, with space left for the tabs to fit back the way they're supposed to (see A).  Here you can see the cut and short jumper that move the pipe key down into the next row (It will now produce the same scancode as the original pipe pad, and the keyboard will work as normal if you put the stock keys back onto it).



Now it's time to put the board back together and see if it still works (place your bets, folks)!  If it doesn't, the mod should be reversible by removing all jumpers and soldering across the two cut traces.

Lol, I hope I didn't break it. XD

[msiegel]

awesome! *crosses fingers*

[bladamson]

Yea, I'm afraid to put it back together.  If I broke it, I'm gonna cry. >_>

So I'm "waiting for the soldering iron to cool down so the cats don't get into it..."

[msiegel]

if you did break it, i'll send you a new pcb

(after my own frankensteinian experiments

[Soarer]

Poor F :-(

For once I'm glad your pictures are small and unclear! :-p

[bladamson]

Timeforatest!



Well,themodsareallfine,butasyoucansee,Ididn'tgetthespacebarhammerbackinright!!



Timetotrythatfishinglinething,Iguess.:3

\\\\\||||

Woot,ANSIlayoutmodelFwithoutanyOS-levelkeysymremappingrequired!

[msiegel]

yes!it'sperfect!:D:D

[bladamson]

MaybeifIshakeitreallyhard.....