deskthority

It's funny that "get a SSK to start with" is likely going to cost as much as everything else put together.

Maybe step 0 should be "Get a regular M and cut it down to SSK size"

Well any M would do really. Just for the test. Had I not sold my second silver label M that board would have made a nice candidate for something like this. But I'm not as crafty as i$ and the whole thing would have ended in chaos.

An SSK is the only Model M really worth doing this kind of work on. Real Model Fs aren't so expensive and have the other (inferior) form factors already covered.

So, I've been thinking. Looking at this picture in particular:



The blocked flippers are for the CV and ,. keys. Those are, sure enough, where the spacebar stabiliser clips are mounted on the top of a Model M barrel frame. Those rectangles that are in the way here are, I strongly suspect, the undersides of the stab clips. They look pretty heavy duty. I wouldn't want to try drilling them out of the way. Better to first try cutting flippers instead.

Another thing is that Model M frames have a lot of plastic ridges on the underside that hold the membranes in place via those infamous plastic rivets. Each row of flippers is actually boxed in by those ridges. But Model Fs have no such thing:



What you see here is discrete switch housings instead. What are the relative sizes I wonder? Model F was designed for a capsense PCB while Model M was obviously not. In Model F, the PCB is held fairly tight against these switch housings. Do the Model M ridges force us further away from the flippers or what?

All,

Let me report that the first problem is resolved: my second SSK can hold all the F flippers:
You will notice that I had to file the epoxy that I added to the channels. The board was not cracked but it was very week. This is why I added the epoxy.

Muirium wrote: ...

The blocked flippers are for the CV and ,. keys. Those are, sure enough, where the spacebar stabiliser clips are mounted on the top of a Model M barrel frame. Those rectangles that are in the way here are, I strongly suspect, the undersides of the stab clips. They look pretty heavy duty. I wouldn't want to try drilling them out of the way. Better to first try cutting flippers instead.

Iti s resolved. Check the post above.

Another thing is that Model M frames have a lot of plastic ridges on the underside that hold the membranes in place via those infamous plastic rivets. Each row of flippers is actually boxed in by those ridges. But Model Fs have no such thing:

In my opinion it is due to a limitation in the tools that could be used in the model F. They couldn't probably create the big plastic piece with all the barrels. What you observed it is just a side effect.

What you see here is discrete switch housings instead. What are the relative sizes I wonder? Model F was designed for a capsense PCB while Model M was obviously not. In Model F, the PCB is held fairly tight against these switch housings. Do the Model M ridges force us further away from the flippers or what?

The model M is nothing that a cheaper way to sense a bunking spring. As I guessed before, it could well be that they could not manufacture something. The membrane for instance. Making a PCB allowed to reuse known techniques.

Nice!

That low angle shot makes me feel a bit better about the ridges, too. They don't seem as deep as I remember them. Good news, probably…

Just out of interest: does this thing work if you put the Model M membranes back on top and plug in a controller?

This looks great, I think this project is becoming more feasible, but I hope my blue label lexmark SSK has the right barrel plate for the job.

Still interested in your model M hammers for the model W i$.

Regarding the M vs F feeling:

I have come to the conclusion that the difference is based on two things:

• 1.- The feet of the model F are larger but thinner. The mechanics on how this set hits the board are different.
  2.- The surface in the F is hard. In the M is not (it is a membrane)

The foam and the way the barrel plate is mounted has little or no impact in the key feeling. The FSSK feels like the F122 !

Redmaus wrote: This looks great, I think this project is becoming more feasible, but I hope my blue label lexmark SSK has the right barrel plate for the job.

Still interested in your model M hammers for the model W i$.

Sorry, I will not get rid of these hammers until I finish the project. PM me. We may have other options using my spares.

Muirium wrote: Just out of interest: does this thing work if you put the Model M membranes back on top and plug in a controller?

I would be genuinely surprised if it did work.
Getting the membranes to touch requires quite a bit of precision regarding the exact point of pressure. The holes in the middle membrane are not really big. And you need a protrusion. That's why there is the nub on the M flippers.

Great job so far i$!

Muirium wrote: Just out of interest: does this thing work if you put the Model M membranes back on top and plug in a controller?

I will test it, but another day. I have screw in an out three SSKs already. Enough for today

Aye. Enough playing. Back to work!

idollar wrote:

Muirium wrote: Just out of interest: does this thing work if you put the Model M membranes back on top and plug in a controller?

I will test it, but another day. I have screw in an out three SSKs already. Enough for today

OK, I will NOT test it as it will NOT work:
The membrane has marks at the flippers pivoting points. If one places the different type of flippers on them, one can see that the M hits where the contacts are. Instead, the F will hit further down. Actually the contact is place under the F-flipper angled section. It will not create any contact in the membrane.

The question has been answered without undoing the screws

now i need a second SSK to turn into the FSSK

andrewjoy wrote: now i need a second SSK to turn into the FSSK

This is the easy part. You will also need flippers and the PCB that we still have to design and produce
The difficult part of this project is in getting the F-flippers !

I am working on reproduction flippers, hopefully there will soon be plenty to go around

andrewjoy wrote: now i need a second SSK to turn into the FSSK

The good news is that you will not need a second SSK. If everything goes fine, you will be able to test it with your exiting SSK. It should be possible to revert the changes without damaging the original SSK. A screw-mod is assumed.

rsbseb wrote:

seebart wrote: I am sceptical it will feel 100 % exactly like Model F. Sure, more like Model F. It is a great idea though. Reminds me I got plenty F flippers around, just no spare ones.

I am working on reproduction flippers, hopefully there will soon be plenty to go around

Great !

I think quite a few XTs will be sacrificed if this works out!
Or Bigfeet!

rsbseb wrote: I am working on reproduction flippers, hopefully there will soon be plenty to go around

Point proved! Another nice photo there i$. I might try cropping it for a header sometime. (Whoops: too blurry! I shouldn't make decisions when browsing at 3.5 inches.)

And I look forward to trying these newly made spares of yours, rsbseb

I have created a new version that would fit better the header ...
I have posted it also in the correct thread

Really interesting! To be honest I'd guessed for years this wouldn't be possible - but the flippers fit and now we have the precedent of Xtant. Go idollar!

wcass where are you?!?!

I am sure his input would be great.

This is really interesting! I'm tempted to convert one of my SSKs, or find a third...

What are the production dates on the two SSKs that the barrel frames are from, more to the point; is it the younger or older that can hold all flippers?

Ungh… I was planning on selling one of my three. But this would be the final excuse for me to bolt mod the one with more than a dozen rivets MIA.

Safe to say there's enough interest to begin thinking about a GB here if this works out well for you i$!

The next steps follow:

1.- Figure out the relative position of the capacitors in the PCB with respect to the SSK barrel plate.
2.- Decide the PCB supplier. I think I will try http://www.pcbway.com/ as it worked with wcass' xtant.
3.- Decide the format of the electronic file: if I understood correctly wcass sent a pdf
4.- Decide the thickness of the PCB - In this case I will measure the original XT and Bigfoot
5.- Decide what to do with the Xwhatsit. It is not thought to be inside an SSK. The usb connector, how to get the cable out ... all these things need to be decided.

6.- Design the PCB with all the constrains above.

7.- Produce some prototypes. if someone is interested, let me know in the next weeks. I guess that the more we are the cheaper they will be. ... the first release will be risky and I take no responsibility.

----

Regarding 1.- I already took some measurements here and there. The transparent membrane with marks on the flippers is making things simpler than what I thought. I will post the progress, latter today (if I find the time)

Please comment, your ideas/feedback help a lot.

i$

Khers wrote: What are the production dates on the two SSKs that the barrel frames are from, more to the point; is it the younger or older that can hold all flippers?

The black one -- the one that accepts all the flippers -- is from 22-JUL-87
The white one -- the one that does not allow for 4 flippers without modification -- is from 23-JAN-91

Good to know. My SSK has a black one, and from my friend as well.

I think I would be in for a prototype if I someone manage to get some F flippers for a reasonable price, and the xwhats controller of course.