[Mod] NiZ Plum75 / BKE dome-swap review, or: let the modder beware!

(This is cross-posted on reddit)

(Note: This post is in reference to this particular Plum NiZ Board ONLY!)

This is a review of my BKE ultra-light dome-swapped NiZ Plum75 RGB Bluetooth keyboard. Disclaimer: all views and experiences are my own and should be taken as such. I’m not advising anyone as to what they should or should not do, only sharing my experience modding this particular board.

I went back and forth for a while on whether I should write this post because on the one hand, I don’t want to discourage anyone from experimenting with keyboard modifications, but on the other hand, most of the guides I read on r/mk, YouTube, and in other forums made this mod seem basic and easy, and it absolutely was not. I’ve also seen several recent posts from people newer to the community asking about modding Plum/NiZ boards, and other people casually suggesting dome swaps because its a mod they’ve heard is simple (despite having, apparently, not attempted a BKE dome swap themselves).

Keep in mind: I’m reviewing this board as someone who does not have a lot of experience building electronics. If you are someone who does, this post may not apply to you.

So, first, some clarification: I modded my board with BKE ultralight domes. BKE domes are sold as individual domes, not as dome SHEETS. You can buy 55g or 65g dome sheets on ebay to swap into the Plums, but that is a different kind of mod. The distinction is important because keeping 75 domes all aligned is not the same as shaping and aligning a single sheet of domes.

The Process:
I bought a pack of plastic car pry tools to help remove the case off without scratching it. If you are going to attempt this mod, UNDO THE PLASTIC TABS FROM THE BOTTOM OF THE CASE. If you start from the top, the case gets wedged in place and is really hard to open.

Once the case was opened and all the connectors unplugged, I laid the board face-down, balanced between 2 equal-height books, put in the springs and the domes, and then went to align the PCB, screw it in place, and put the board back together.

This is where it all went awry. It took me maybe 10 tries over the course of 2 days to get it all lined up and reasonably functioning. The plum75 has large lock-light LEDs above the caps-lock, and on the top left FN row. In the process of aligning and screwing everything in the LEDs became tangled in some of the coils. Worse, when I went to align the PCB to the board, the LEDs would bump all the domes near them out of position, so when I went to test the board, either a dome would be misaligned in the key, or certain keys wouldn’t work (or both).

After taking the case off, disconnecting the ribbons, unscrewing the PCB, realigning everything over and over again, I finally settled on ENOUGH keys functioning that I’m fairly certain I will never tinker with this board again.

A general warning about the Plum: the PCB is kind of flimsy. Even before I opened up the board, the space bar had started intermittently not registering. Fortunately this is the board I used for work at the office so I’m less concerned about it being beat-up or imperfect.

The Outcome:

  • Currently the capslock, escape key, and fn keys 10-12 no longer function. The LED got entangled in the capslock coil spring and warped the spring so it isn’t useable anymore.
  • The RGB no longer works (the esc key controls the RBG and that no longer works)
  • I havent tested out the bluetooth function but since the key that controls it isn’t registering, I imagine it won’t either
  • The comma, question mark, and apostrophe keys need to be hit extra hard to register
  • the FN key sticks
  • there is something rattling around inside the board (probably a case tab that broke off or a screw)

The Positive:

  • Props to Keyclack because the ultralight rubber domes are wonderful! I cannot tolerate heavy switches for extended periods of time, and these switches are remarkably tactile without fatiguing my fingers.
  • A HUGE thank you to Vvanderfell on reddit for suggesting that I buy the detailing tools, providing an excellent dome-swap guide, and just generally going out of his way to offer guidance and support. I’m not as skilled at keyboard modding as he is, and I couldn’t have done this without him.

Final Note:
Before doing any mod, know what you’re getting into. There are many skilled modders on r/mk and they can make it look easy (and may even claim the mod was easy!), but your own personal mileage may vary.

TLDR: I swapped BKE ultralights into my Plum75 RGB Bluetooth board and while the keyfeel is greatly improved, the board no longer functions like it used to. Also, the Plum/NiZ PCB and build quality may not be so good overall? (I’ll leave this last statement to debate among people who know more about keyboard build quality than I do).


Man I really wish you had pictures of the disassembled case, having done this to my HHKB there’s so many steps/items listed in your horror story that just don’t exist on my board and makes it hard to visualize the issues.

So sorry for all the problems!

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vvanderfell has pics of his disassembled case on reddit if you want to search. i think the only difference is mine was RGB and his wasnt.

This album right?

yes. and he had another guide where he dome-swapped a plum87 or plum84. i also found a video on youtube and another post on reddit covering it. i dont havve access to it now, but i have a whole folder of resources bookmarked at home

Your experience sounds totally different than mine! I have the Plum 84 and did the swap with BKE Lights in < 1hr and all keys worked the first try. That said, my board doesn’t have LED’s and it sounds like that’s what caused a ton of issues for you.

Maybe this should be beware NiZ Plum RGB* modders?

Oh my,

you reminded me of my modded Plum. I’ve changed the domes, too, from 35g to 55g.
It had been a pita, tough to open the case, “cheap” pcb, and a lot less screws to stabilize in comparison to a Realforce. Two screws even stopped working 100% afterwards, I needed a lot of trys to make all keys working, and afterwards i thought, it wasn’t really worth it for my taste. Lesson learned, there is a reason they’re so “cheap”.

Other folks mileage may be different and that’s fine!

Some old pictures:



thanks for posting the pictures. two of my screws stopped working as well. the funny thing if is you visit the NIZ website, the newer models are more expensive, seemingly without any increase in quality (theyre in the $120-$160 price range now).

yes, thats why I made a note at the top that this post was specifically in reference to the exact board i have. the LED lock-lights were a big source of difficulty. if they make boards without them, i imagine those are much easier to mod. (theyre probably cheaper overall too)

100% I had the same issue. I’m pretty sure the PCB is all messed up now after opening mine up to do the same mod. Except now, my keyboard left CTRL and Windows keys constantly chatter opening up programs and hitting shortcuts as soon as I try pressing anything. I’ve contacted the Niz Rep on Reddit and emailed their customer service and I’m waiting for a reply. I think these PCBs are pretty fragile but I love the build and especially for the price I don’t feel bad moving it to and from work.

For reference, I’ve successfully opened up and modded my RF 87U and Novatouch with no issues. Hopefully I can do something with this board or it’ll just be a housing for spare TMX sliders and conical spring :confused:

Yea i really love the design of the NIZ boards, warts and all, but they do seem too finnicky to reliably mod, although some people reported having no problems. I would do the same mod on the 84-key layout, which I think I might like a little more, but I heard that people who attempted it had similar difficulties, and the PCB still has lock-light LEDs on it. I also get occasional chatter on the apostrophe key.

Please let me know if NIZ ever gets back to you with an answer.

I had this happen on my ABKO Hacker K945P, which has pretty much the same PCB as the Plum87. I believe it turns out these PCBs are really sensitive to precise placement of the springs and domes. I had to very carefully make sure each and every dome was exactly centered in each key (there’s a somewhat helpful white dot in the middle of each key) and that every spring was exactly centered in each dome. Then, I had to very, very carefully lower the PCB as straight as possible over the whole shebang and screw it in with the exact right amount of force per screw. It’s a painstaking process I had to repeat two or three times per reassembly :disappointed: Also, I found it easier to do this by precariously suspending the keyboard facedown (keycap-side down) by its case’s edges. Some people do this with books; I had a bunch of small, uniform cardboard boxes from my multiple NovelKeys orders :laughing: I had to be very careful not to bump into the boxes, or else the keyboard could fall and send domes/springs flying :fearful:

Then I found I didn’t want to clip the corner off 87 domes to get backlighting to work again, so I went back to the offbrand, cut-up 55g dome sheet I had purchased before deciding to try BKE Redux domes :stuck_out_tongue: But I got some good practice doing the above alignment dance!

I am not sure if previous experience with modding proper Topre boards can actually help here.

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I had the same issue when swapping 35 to 55g and came to a conclusion that it is almost impossible to line them up so they will work perfectly.
But here goes the most interesting part - you just need to calibrate them with calibration tool from niz official website. After so many hours of struggling that was like a miracle for me.


I had no idea there was a calibration tool on the NIZ website. I still think NIZ makes great knock-around boards, and for the money they sound better than Topre. I just dont think I would ever attempt modding one again.


As someone who recently decided to open her board and fiddle with the stabs, I can say with certainty that the calibration tool saved my board.

I spent two days and at least a dozen attempts trying to manually get the alignment perfect before I found the calibration tool. It saved my board and went back to 100% functioning.

Tip for the future in case anyone reads this: The “InitialCalib” helped me get around 95% of my board functioning normally (I think it re-registers where the spring is contacting the plate, so it doesn’t need to be 100% aligned as it was before).

There were still some buttons which didn’t respond 100% of the time after that (so let’s say I press the ‘S’ key 10 times, it may skip once or something). For those keys, hold the key and press the “PressCalib” button to calibrate the individual keys.


if Niz start releasing their keyboards in stock with alu versions, I think will be a good buy (provided the pricing is not too crazy)!