What is SpaceFN and why you should give it a try
The SpaceFN concept - setting up your space key as a layer switch when held - is probably one of the most useful tweaks in the keyboard hobby. Let me explain how it works. My SpaceFN article on kbd.news made some rounds recently - quite surprisingly given the age of this concept. This piece you're reading is a condensed version of the full post. If you're left with unanswered questions, you'll most likely find the info you're looking for in the original write-up. On my imaginary top list of the most useful keyboard features, tweaks and hacks, SpaceFN would deserve a podium finish for sure. But what makes it so special? In short: SpaceFN is easy to implement, easy to learn, costs nothing, can be used with any keyboard, and can improve your productivity instantly. I will list its benefits below, but can state right at this point that the SpaceFN concept, setting up your space key as a layer switch when held, is clearly one of the most useful tweaks in the keyboard hobby....
Apr 30, 2024
ABS
ABS is easily one of the most commonly used materials in the injection molding industry (notably, LEGO are made of ABS). It’s durable, well understood, and very easy to work with. Because of this, it is the most commonly used material in keyboard keycaps, whether for mechanical keyboards or not. There is one big downside though - shine. Chemically, ABS is less resilient to the oils on our fingers and in our environment than both PBT and POM. For example, as with LEGO, acetone will destroy your ABS keycaps. I don’t expect anyone reading this to be covered in acetone while typing (that would be hard anyway, considering the vapor pressure of acetone, but this isn’t a chemistry lesson is it?), but some lotions and other substances found around us and on our fingers can have a similar effect on ABS keycaps over time. Despite the long-term issue of shine with ABS keycaps, the ease of manufacture and versatility of legend capabilities (it is far easier to make doubleshot ABS keycaps than from any other material) makes them a very common material of choice, particularly when designing complex color combinations that require doubleshot manufacturing. In terms of feel, ABS has a more classically “plastic” feel to it, resulting in a more high-pitched sound profile. If that sounds like a negative description and you haven’t tried ABS, don’t write it off based on that though, a quality thick ABS keycap set is nothing to scoff at. PBT
PBT as a material addresses the one issue with ABS, introduces another problem, but solves it in a unique way. PBT is chemically resistant to pretty much all oils and greases that you would naturally expose it to, so it is very hard to shine a PBT set - awesome. On the flip side, PBT is harder to process and until the last decade or so there were no doubleshot PBT sets available. Even with the existence of doubleshot PBT sets now, they are not terribly common in the enthusiast space and for some reason most of the sets I’m aware of are on the lower quality side of things (not really sure why that is, but if you know of some premium doubleshot PBT sets that I’ve missed, let me know!). That’s not to say they’re bad sets, but when you get really picky about legend quality it becomes harder to find perfect quality sets. Despite the shortcomings of PBT as a doubleshot material candidate, it does have one great trick up its sleeve. PBT can have legends applied using the dye-sub legending process (detailed below), which results in equally durable legends as doubleshot keycaps. They do have one small drawback in terms of color combination options, but overall they are very nice keycaps and preferred by many enthusiasts. In particular, PBT is sought after by many for its softer and more …forgiving…(?) feel. It’s a very comfortable typing experience - if the colorway/theme you’re after is available in PBT, you really can’t go wrong. POM
Doubleshot
Doubleshot manufacturing of keycaps is the process of shooting one color of plastic into a small cavity, then injecting a different color of plastic around that initial shot of plastic to form the rest of the keycap. Doubleshot keycaps are incredibly robust in terms of legend durability because you can’t rub the legend off - it’s physically built into the keycap. This means that even if finger oils were to eat away at some microscopic layers of the cap, it will have no noticeable effect on the legibility of the lettering itself. Tripleshot
Dye-sub
Dye-sublimation is a technique used to transfer “ink” (the dye-sub industry may have a different name for it) from a substrate onto/into the surface of a keycap. The process doesn’t literally sublimate the material - it’s a bit of a misnomer - but does cause the legend coloring to diffuse into the surface of the keycap. This diffusion of material into the keycap results in a similar level of robustness as observed with double and tripleshot keycaps. Because the legend is literally baked into the keycap itself below the surface, some layers of material can be removed and the legend is still present. As you can imagine, dyeing a dark material with a lighter material (white legends on black keycaps, for example) is unlikely to yield successful results. One inherent limitation to the dye-sub process is that the legends must be darker than the overall keycap color. There are some small-scale “reverse dye-sub” processes floating around that dye the entire keycap except for the legend, but this is less common and I haven’t had the chance to inspect any myself - your mileage may vary. One additional potential downside to dye-sub legends, particularly with lower quality sets, is the possibility of legend bleed. The legend ideally should only diffuse down into the keycap, but sometimes it will diffuse to the sides and create a fuzzy/blurry effect around the legend. Higher quality dye-sub sets will usually not have this issue, but it’s something to be aware of when looking. Others (UV print, pad print, laser infill)