A bunch of questions for a newb

I can’t believe how involved the world of mechanical keyboard is! As I’m getting started on a project for a replacement keyboard for a retro computer, I have a bunch of questions I hope you all can answer

Keyswitches
I see that Cherry is the big name in keyswitches, but their standard Cherry MX is too tall for my application. They’re supposed to have a low profile one coming out, so I spoke with them and said Digi-key is going to have them. Checked with Digi-key; they don’t yet.

Question: are their other manufactures that have a low-profile, quality mechanical key switch? The original retro one I’m basing it off of is 9mm tall (without keycap).

Keycap Families
I know that DSA stands for: “DIN, Spherical, All-Rows” But what do DCS, DSS, SA stand for and what are the differences?

PCB
@VinnyCordeiro suggested I use KiCad to develop the PCB, thanks for the recommendation.

Question: what’s the best and most inexpensive PCB keyboard vendor? The current retro PCB is 285mm x 109mm x 2mm

Kailh Low profile switches might work for you

Keycap Families
I know that DSA stands for: “DIN, Spherical, All-Rows” But what do DCS, DSS, SA stand for and what are the differences?

The D in DCS and DSS, all stand for DIN, which was an older German keycap standard.
DCS is DIN, Cylindrical, sculpted
DSS is Din, Spherical, Scultped
SA did not meet the DIN standard at the time, but they have the S for spherical, and I’m not 100% sure about the A.
The differences in the profile is their sculpt.

DCS Sculpt:
image
DSA Sculpt:
image
SA Sculpt:
image
DSS Sculpt:
image

Hope this helps you out a bit :slight_smile:

9 Likes

Thank you for that history. I didn’t actually know what the profile acronyms were!

2 Likes

You can take two routes: go to pcbshopper.com, enter the parameters of your PCB, and let the site shows you the price comparison between a number of fab houses.

Or you can go straight to jlcpcb.com, they consistently have the lower price on the market and a fairly good quality.

2 Likes

There’s tons, different ones have different strengths depending on what you’re looking for (board size, assembly, lead time, etc). I think JLPCB is a pretty popular one (although I’ve not used it). PCB way and Seeed Studio are ones I’ve used (although not for keyboard projects). OSH Park is good if you want to keep it in the states, but their pricing doesn’t scale very well with board size.

1 Like

Hi. Welcome to the rabbit hole.
You might have difficulties finding cool keycaps if you go the Kailh Low Profile Route. I saw Cherry MX Low Profile switches online. The are compatible to most custom keycaps. I never tried them. They are linear which should be a good thing for low profile imo.

1 Like

Yeah, I saw those too. I contacted Cherry and they said that Digi-Key is the only one that’s put the part # in their system. Contacted Digi-Key, as there’s a 9-week lead time listed, but haven’t received a response yet.

I have a Cherry key tester kit, and like the linear with a bit of tactile resistance, but haven’t tried any of the Kailh ones. I read they’re not as good, but would love to hear everyone’s opinions.

Thanks Vinny!
I put in the parameters in pcbshopper and was a good starting point to get a budgetary number. Since I’m new to all this, I have a huge learning curve to get over but pretty excited to learn to build the PCB in KiCad.

You can always harvest the switches from a donor board. AFAIK only the Cooler Master SK600 series uses them. Exclusivity contract? That has been done before, could be the case for the unavailability now.

1 Like

Me either,

LOL :upside_down_face:

I was gonna suggest the same to the OP for getting some Cherry low-pro switches without having to wait on Digi-key. Although it will cost substantially more than buying a batch of them on their own.

eBay is your friend. :wink:

1 Like

Was on KBDFans site and saw this “DSA BLANK KEYCAPS 1.25U 1.5U 2U”

What do the “u” designation mean in 1.25U, 1.5U and 2U?

For a prototype board, this is probably to best way to go. If the Cherry low profile works, I’ll need to find out how when they’ll be available…assuming they won’t cost a bunch

1 Like

A remark to your great post: DIN is not a keycap standard! It means „Deutsche Industrie Norm“ a generic German industrial standardisation name. Lots of things are DIN in Germany.

2 Likes

DIN is the German technical standardization organization, as ANSI is for the US, ISO is for Europe, JIS is for Japan, ABNT is for Brazil, and so on. :slight_smile:

That represents the width of the keycap. A common keycap, like the ones for letters, are the unit so they are called 1u; the bigger keycaps have their sizes rated in relation to the unit. They will always be a multiple of a quarter of unit.

Just for information: the standardized distance between two 1u keys is 0.75in (19.05mm), so 1u keycaps will usually be a little smaller than that (typically 18mm, but that can vary).

1 Like

So I found a SK630 relativity inexpensive on email and disassembled it. It may work in my retro-computer, but I think to actually get the switches out, I have to de-solder each one of them. As there’s a top plate and bottom PCB (see pictures).

I know how and where to build a PCB prototype, but not sure how/where to get a top plate made.

I think my next course of action is:

  1. De-solder all switches (hopefully that will allow me to separate the layers and pull the switches out)
  2. Take measurements and create a layout. If the solution is feasible…
  3. Create a PCB in KiCAD
  4. Find a way to create the top plate

IMG_0164