Thoughts of those FR4 Sandwich case boards

Curious if any would be able to provide some insight on their experience with any of the FR4 sandwich plate boards. Mysterium, Keebio boards, etc.

Building them looks super fun, but how do you like the board after? Do you miss a case? How do you like the sound?

I am interesting in hopping on LCK75: [IC] LCK75 round 2 | affordable THT 75%, and overall I am curious on what you think of a similar build you may have done after you finished.

Cheers! and thank you!

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Honestly, I’ve built a couple now (Nullbits Nibble, Keebio Sinc, SplitKB Kyria) and I’ve got more to build.

I’ve yet to just use them in the raw as it were. There’s something in the back of my brain that says, “I’m not going to like the way this sounds”. So in each case I’ve either bought, or designed and printed a tray or case for them.

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I have a Keebio BDN-9 macro pad, and I love the sound it makes. That said, I’m not sure how I’d feel about the ergonomics of a full board made that way, with the flatness and sharp edges.


That is kind of my thought too, better to get a case up front. @Extra_Fox

I could always build a case later with the files if I want, but I suspect that will just be something I never get around too unless I do it from the start :stuck_out_tongue:

I’ve built a few and they’re my daily drivers lately, but I don’t care a huge amount about the sounds. I would prefer to have a case for them, though… going to have to get a 3d printer someday. Waiting for IMK Corne case to arrive at the moment.


I have build several (3 lilies, 3 nyquist and 2 corne). Surprisingly, FR4 sounds good. It’s only disadvantage is that it’s a light material. I personally like when board feels like brick on my desk LOL.
The extra weight does make the board sound more “solid” and the board doesn’t move when you accidentally hit it when jumping between the board and the mouse.

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I agree that FR4 sounds good. What I dislike about FR4 sandwich boards is the bottom, making the board too tall and too loud. My solution was to replace the bottom board with foam.


There are two very good cases available from the P3D store that will add a ton of heft and the store runner will customize it for you upon request (for example, if you e-mail him he may be able to have a 3mm brass plate cut for it instead of acrylic).

These cases also sound phenomenally good.

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they look kinda crude imo and I would worry about ESD, but they tend to sound nice (at least to me) and are usually a solid cheaper option

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Personally FR4 if my favorite material for keyboards, but only inside of a decent case. While I have used my fair share of sandwich mount, tray mount, and Rawdog PCB boards, they feel unfinished, and lack any definition when it comes to how they feel to type on.
They’re a great way to try a layout you’re not sure if you like, but I personally can’t got without a pretty case to cover it up andenhance the sound profile of the switches.


My personal take is that after watching this video I know can’t wait to build my own V2 of it which is open source and it also comes with a case if you really don’t want it fully open. I think that regardless of everything it’s a board that everyone should have because probably that is as raw and pure as it gets when it comes to experiencing a keyboard.

Moreover the fact most of them are fully open source and they detach you from the usual group buy nightmares is another huge “selling” factor for me.

Thanks everyone for your opinions! I was leaning towards wanting a case, and I think the thoughts here validated that.

The P3D cases look awesome, it just increase the total price a bit. Luckily I have some time to decide if I want to take the plunge!