New HHKB and a rant about lubing
My current opinion is probably to pass on lubing unless you’re trying to silence some rattle on the spacebar. The cost and time for what you get out of it is probably the most marginal gains/side-grade thing I’ve done.
I recently got my first HHKB, a Professional Classic Type-S, after using a MacBook Air keyboard for years. Out of the box, I was very pleased with the feel. It is better than the Realforce boards I have owned, at least to me, and the layout took no time to get used to.
Not wanting to leave good enough alone, I decided to lube it. My spacebar had a small amount of rattle, and I figured I could improve it. I opened it up to lube it, and now I have some takeaways: several HHKB lube guides repeat the same advice without always explaining why, and the process is much more time-consuming than it needs to be. To be fair, most of them at least provide clear pictures or videos to follow.
First, most guides seem to recommend painting the thinnest possible coat of grease onto each side of the slider rails. I tried that, and it sucked. I then tried applying grease more freely and wiping away the excess. The second method was much faster and gave me more consistent results. I was surprised by how consistent it was, since that was one of my biggest concerns going into this.
Same deal with bag-lubing springs. If you enjoy separating and shaking a pile of tiny springs, go for it. Otherwise, wear gloves, put a small amount of oil on your thumb and forefinger, and pinch each spring as you go. It is faster and does the job.
What I found lubing the stabilizers
A heavier application of tacky grease can remove existing rattle. The sound change outside of that is a side-grade, but removing the rattle was welcomed and was the most significant change from stock.
For grease choice, I spent too much time reading data sheets and trying to understand the choices mentioned in the guides. I went with Krytox GPL 207 because I have used several Krytox GPL variants on O-rings, gaskets, and weather stripping for years without them becoming dry paste. 207 is the thickest, tackiest version of what I am already used to.
GPL 206 comes up frequently for stabilizers, and I do not really understand why. This honestly made me second-guess myself. I assume 206 is more available through keyboard vendors, because I do not see a performance reason to choose it over 207 for stabilizers. Most of my grease comes from McMaster, Zoro, and Grainger, so that may be part of why I see the options differently.
I think 205g0 would work well too. In retrospect, if I wanted a one-grease solution, I would probably use 205g0 all around. I’m in agreement with the guides that recommend one grease. Or just use Haynes silicone grease on the stabilizer and skip the sliders.
What I found lubing the sliders
This was the biggest letdown of the whole process. Based on how people talk about slider lubing, I expected it to change the board much more than it did. Maybe my HHKB is a unicorn in the QC department, but for me it was a side-grade.
I used 205g0, which I had to get from a specialist keyboard vendor. It worked well for removing the small amount of scratchiness my HHKB had; do not expect a dramatic transformation. I don't think I'll do this again.
It will not make the key press lighter. A correctly functioning slider should already fall under gravity in the rails. It also will not substantially dampen the key press unless you use a much heavier application, and that is where it goes wrong. Go heavy on the grease and Topre turns into mush or some weird linear sponge. I strongly dislike the feel of an over-lubed Topre slider.
The guides I used generally did not recommend lubing the Shift, Return, and spacebar sliders, but I did. I do not understand the advice to avoid them. They are still sliders. You are not going to match their feel to the other sliders anyway, because even stock, they feel different. Mine had similar results to the other sliders.
What I found lubing the springs
To be blunt, this was pretty worthless. I used GPL 105. I read some recommendations to lube the PCB, which I found funny. Skip this.