The Franken XT - XT Case and Wheelwriter keyboard assembly (updated pic w/coverplate)

[SunshineRag_DT]

FrankenXT.2jpg.jpg (1.01 MiB) Viewed 2527 times

(cross posted from my r/modelm post, updated pic with added coverplate)

UPDATE 1-29-23: Finally able to modify the Wheelwriter cover and overlayed on the barrel plate to get color matched blockers. Made the entire build look much better almost like it was supposed to be this way. Now completely working with QMK.

You may wonder what happened here. First off why would I do this to a Model F?

The story is that I actually acquired a case and plate for a Model F XT as a project to do a XTant build with a new AT compliant PCB layout and an xwhatsit controller. I never sorted out how to build the XTant top plate, therefore this was never a complete F XT and I never got around to doing that, although I still might.

Coming back to what this is. I saw a post a while back about that a Wheelwriter assembly might fit into a Bigfoot. I didn't have a Bigfoot case but I did have this. Since I have a spare XT case I am not using, I wanted to see if the Wheelwriter assembly fits. Of course the Wheelwriter is using Model M flippers, but it does allow an interesting layout with that funky Code key.

The short answer is the Wheelwriter assembly does not fit out of the box (it is 1/4in too wide and too tall), so it needed some plate modification. But the layout certainly does fit and after simple modification of the Wheelwriter backplate you can get it into the case, as seen above. There is still more to do, tweaking the keyboard assembly placement, and I am going to try the new MStar controller with it after mapping out the matrix. But it all fits and looks doable.

Is this a good idea, probably not, but I do like to try odd things and will post again to the Workshop if I get it all together. Also as there are traces for the German layout under the LShift, it might be possible to membrane hack and mod the plate to get an LAlt, and maybe an ANSI Slash if I get around to bolt modding and looking at the membrane layout. But that would be a bit down the road.

[zrrion]

I hate this but also I love this. I hope you do more stuff like this in the future

[Icarium]

Yeah, the lack of some modifiers in the bottom row is really the only thing that is keeping the F AT and XT from being basically a fully functional TKL board.

[SunshineRag_DT]

Yes the lack of modifiers is a concern, but even though it looks funky with the Code key there are at least two modifiers on the bottom just like the XT and AT. As I mentioned there are some unused matrix positions in ANSI layout around the LShift and Enter that might be repurposed, with some effort, to get another modifier on the bottom row. Another plus is with QMK available on the MStar I can test tap and hold modifiers.

Once I get the matrix fully sorted will poke around and see if there are any additional modifier options available. It appears to be a 14x7 matrix using 2x15 pin ribbons.

At least with the Wheelwriter I have a basic TKL, whereas with XT it would be difficult to get a usable arrow cluster, and that row 3 row above the Nav is actually more interesting than most realize. I have seen some reconfigurations but with the XT none of them were very satisfying due to the limitations of the XT layout. That is why I was looking at an XTant build with this originally. I understand that the AT has more modifier options with some hacks, but I dont have an AT.

[orihalcon]

Case modifications are always interesting. Good deal if it works better for your needs. I like the large CODE key that can almost be used as a split shift, good news is that you can fit those to regular model M's or F's with some spring rearrangement if I recall correctly.

Reminds me of an 87 key model F with an XT case I made a while back shown here: https://geekhack.org/index.php?topic=71408.0

I get the layout frustrations with the XT though. The XTANT also was an interesting option back in the day, but the extra wide arrows were a little different. Never tried one though.

[SunshineRag_DT]

Reminds me of an 87 key model F with an XT case I made a while back shown here: https://geekhack.org/index.php?topic=71408.0

I really like that, but dont think I will run across a 107 to scavenge for such a beast. That is probably what XTant should have been, instead of those wide keys. With the new Model F it is not hard to get extra F barrels and flippers now days. Unfortunately getting a custom curved barrel plate is not easy.

I would really like to see if there could be a 3D printed or injected molded barrel plate could be made. You could even make a layout that uses existing F barrels. With the ability to make a F PCB and the xwhatsit the plate is really the only thing that makes a custom layout more difficult. It is really hard if not impossible to hack the XT barrel plate to get a different layout. If you could make a plastic barrel plate that just clips to the XT backplate you could go hog wild with custom layouts for the XT case.

For this thing if I can hack an extra left modifier, and get tap mods working, it probably would be just fine for me. The Wheelwriter keys feel pleasantly different than my Mini M and Model Ms I have, not quite sure I can describe it. Maybe a little crisper and a touch firmer. The keycaps also seem a little different slightly more textured in a nice way. The spacebar is a clacky mess though, but I have not relubed the stabilizers yet.

[Icarium]

Reminds me of an 87 key model F with an XT case I made a while back shown here: https://geekhack.org/index.php?topic=71408.0

That looks like damn nice keyboard. Does anybody know if one of those projects for making replacement PCBs for the capacitive IBMs actually worked out?

[SunshineRag_DT]

I was able to map the matrix, typing on it now! Used Level1Techs MStar controller, Mini M version since it has the dual 16 pin triomates, as Wheelwriter's actually have 2x15 trace connectors although it only uses half (8 traces) of the row connector of course and only 14 if the columns as column 0 has no trace. I have a QMK configuration and will see if I can post it to Workshop in the next few days. You could use one of the Model M versions with the 8 or 12 pin connectors but you would have to cut the membrane on the row connector.

All in all pretty painless with a little futzing with QMK to add the configuration.

[Findecanor]

Awesome! I really like it.

[SunshineRag_DT]

Added a build log for this in the Workshop.

[SunshineRag_DT]

Updated the pic for the final look and fully working now using QMK.