A.87 tkl pcb


#1

Hi,

I’m relatively new to mechkeys, and super new to kustoms. I recently won the raffle for a kira80. This is not related to the Kira 80 itself, but please let me know if asking here is inappropriate. I did not want to ask these questions on the GB thread.

What is an A.87 PCB ? Is it a specific PCB or a form factor ? Are there many variations of this ? Where can I find more information on tkl PCB styles, form factors and options out there …


#2

Getting right into the deep end are ya? Haha.

Okay so the whole A.87 thing got a little muddy over the years. Originally this form factor was made by an otd.kr member but it went through a few community revisions afterwards. First off, here’s a size comparison:

The main differences are the size (the PCBs got smaller over the years) and the stabilizer orientation. In most cases neither will matter, but for completeness sake, the original orientation is:
left shift: wire under key
spacebar: wire south of the key
right shift: wire south of the key
enter: wire north of the key
backspace: wire south of the key

After a while people realized that Cherry stabilizers wobble and rattle more if the wire is south of the key, in specific rows, though. So people started rotating them.
Then there’s the whole B.87 mess. The B.87 PCB was made by winkeyless and is smaller, has a few rotated stabilizers and has the USB port on the left side. Then some wonderful people got the idea to use that general design, but put the USB port at the A.87 position while not renaming their creation.

So, bottom line: look for the even 0.25u spacing, with the USB port right next to F12 and at the top side of the board. Anything else should just fit unless the plate was made to be an ultra tight fit around the stabilizers which isn’t that common anymore.


#3

@kawasaki161 This was super helpful. Thanks a bunch !!!


#4

yeah this really is super helpful, thanks kawasaki.

coffee because the pcb for the kira is bespoke it might make sense to wait on getting the pcb that comes with the purchase before thinking about buying an aftermarket pcb. users can compare the sizes of the pcbs they have to the one that comes with the kira to help you decide on which aftermarket pcb you’d want. i have a tx87-l3 already so i can do that comparison when the time comes.


#5

The TX87 PCB works fine on a KIRA 80 Poly prototype.


#6

Confirming this. My Kira80 prototype also uses the TX87 PCB.


#7

@magicpretzel @yonghf just out of curiosity, how come you folks have prototypes of the kira80 ?


#8

Because we know each other personally.


#9

and we got skammed.


#10

Willing victims though, and still asking for more.


#11

skammed long-term.


#12

Nice !!


#13

TX87 PCB also fits in a Duck Unicorn and Orion, you just have to Dremel that bottom lip down a little.


#14

After a while people realized that Cherry stabilizers wobble and rattle more if the wire is south of the key, in specific rows, though. So people started rotating them

This here is a point of confusion/argument for most. I have heard this argued both ways. The old OTD’s used North stab wires but to my knowledge the exact opposite of what you said here occurred. Many have argued that south is less rattly, this is according to LZ and other makers. You can also check out the TKL compatibility list here:

you can see that most TKL PCB’s are now made with south stab wires whereas the old school PCB’s like the NerD that havent been changed in years still have the north space bar stab…


#15

Interesting, I’m not sure how old of an OTD you are talking about but even the 356l had the stab-wires south of the switch.

From what I’ve seen Korean makers tend to stick to keeping the wire south of the key, that’s correct. But I’ve seen a lot of other makers make use of north facing wires (two examples being Moon and Evil80) and my personal experience shows me that it’s a lot easier (for me, I guess) to have less wobble and thus less rattle on north facing wires.

If done right, both can feel well though, so whatever, people rotated stabs and now there are different orientations on the same size (and kind of also same standard) of PCBs.