Husky Linear Switches
It seems that no matter how advanced switches become year over year, there will always be a large part of the community that insists “all linear switches feel exactly the same.” While I can understand the simplicity of that take if its given from ignorance, anybody who has actually tried a few of the interesting design quirks and twists on the conventional MX-style platform that have popped up in recent years will know that there’s quiet a lot of variation even in the most “mundane” of switch styles.
Of the alluded to variations from recent years, though, none have caught on or expanded into a staple of linear switch designs quite like that of ‘long stem poles’. Once a niche design quirk to provide harsh, punchy bottom outs in aggressive tactile switches like Moyu Blacks back in 2020, long stem poles have become a regular design feature of linear switches more recently and are now a key point of marketing for many new releases.
However, I recognize that the phrase “long stem pole” can be a bit ambiguous to those freshly entering into the mechanical keyboard hobby and looking for some switches of their own. So, let’s go ahead and explore a bit about what long stem poles actually are, how they impact the feeling of a switch, and even some direction as to which brands are featuring this in the designs the most!
Stem Poles and Slider Rails Labeled on a Switch Stem.
Before we actually step into what long stem poles do to a switch’s performance, it’s probably important to clarify what stem poles even are in the first place. As can be seen in the image above, stem poles refer to the long, cylindrical center of the bottom half of a switch stem that acts to help keep the stem positioned vertically when it is being pressed into the switch. While slider rails, which are also labeled above, also do aid in keeping the vertical orientation of stems, they also serve as the bottoming out point for conventional, MX-style switches. That is to say that when a switch’s stem is pressed all the way into the bottom of a switch and can’t be pressed in any further, the main point of contact between the stem and bottom housing is that of the base of the slider rails. Conventionally, this occurs after about 4.00mm of total stem travel distance.
However, if we were to increase the length of the stem pole in that same hypothetical conventional design, eventually it would contact the bottom housing before that of the slider rails and cause not only a different feeling at bottoming out but also a different total stem travel distance. Depending on the length of the stem pole, as well as some other geometries of the bottom house the stem is being pushed into, travel distances can be reduced all the way down to a sub-3.00 mm level! In turn, what you get is a switch that has a much shorter range it can be pushed in and a much more abrupt, pointed feeling bottom out due to its smaller area of contact with the bottom housing.
For an example of what this difference in travel distance might look like, lets look at a comparative force versus displacement graph, otherwise known as a ‘Force Curve’, between a switch with a normal stem pole length (Cherry MX ‘New Nixie’, 12.40 mm) and one with a long stem pole length (Aflion Blush, 13.80 mm).
Comparative Force Curve between Cherry MX 'New Nixie' and the Long Pole Aflion Blush.
While this example is a bit of an extreme one, it does well to highlight just how much difference can be gained when a stem pole is increased by literally one millimeter in length. In addition to feeling different at their respective bottoming outs as a result of differences in the material of their construction, the overall travel distance of the Aflion Blush switches is almost 25% shorter than that of the Cherry MX ‘New Nixies’ just because of their long stem pole!
Trust me, I can hear what some of you are already thinking right about now: “Alright, all of this neat, Goat, but you still haven’t even specified how long a long stem pole actually is and where I can find some!” Unfortunately, I’m going to have to disappoint those of you who feel a bit weirded out by my psychic powers and point out that there really is no definition or specific number that qualifies a switch’s stem pole as being long. While a specific number being measured could be a good metric, the more pointed bottoming out onto the stem pole that people have come to associate with ‘long pole switches’ is a function of both the length of the stem and the bottom housing shape too. If a bottom housing is particularly deep, for example, the longer stem pole may not actually even be the point of bottoming out even though the stem itself is longer than average. Thus, there is some amount of ambiguity as to ‘long pole switches’ given that people don’t have good measurements of both stem lengths and bottom housing depths.
That being said, though, I do at least have some measurements of stem lengths on their own that may help provide you some insight. In fact, I’ve measured over 400 different switches by hand as of the time of writing this article and have found traditional, MX-style switches with stem poles ranging from 12.02 mm in length (Outemu Ocean Silent Linear) all the way to 14.06 mm (SKYLOONG Pink Iceberg), with the overall average being 13.05 mm. As a result of these measurements which I’ve collected over the years, I’ve always loosely held the belief that anything above approximately 13.25 mm in total stem length is worthy of being considered a “long” stem pole. As for how these measurements are distributed across various switch manufacturers, see the following box and whisker chart below.
Stem Pole Length Measurements by Manufacturer.
As can be seen from this chart, only three brands exist on average beyond the vertical green line that corresponds to my arbitrary 13.25 mm definition for “long” stem poles – Aflion, Haimu, and SOAI. While nearly every manufacturer has long stem poles somewhere in their offerings which I’ve measured, there are four brands which are the exception – LICHICX, Cherry, SP Star, and Momoka.
With all of that laid out before you, I hope that this article stands as a good jumping off point to aid in your search for long pole switches, that is assuming they interest you at all. If they aren’t quite your thing, or you are looking to learn a bit more about switches in general, why not check out my other articles here on Kinetic Labs like ‘An Introduction to Clicky Switch Mechanisms’ or ‘An Intro to Frankenswitches for Mechanical Keyboards’.