| Switch Type: Clicky |
| Actuation Point: | 2.5mm | Actuation Point: | 2.64mm |
| Actuation Force: | 55gf | Actuation Force: | 56.0gf |
| Total Travel: | 3.8mm | Total Travel: | 3.57mm |
| Peak Tactile Point: | 2.5mm | Peak Tactile Point: | 2.56mm |
| Peak Tactile Force: | 55gf | Peak Tactile Force: | 69.4gf |
| Reset Point: | 1.0mm | Reset Point: | 1.22mm |
| Bottom-out Force: | 59gf | Bottom-out Force: | 69.5gf |
The IBM Beam spring switch – a tall, plate spring, capacitive clicky switch. These switches can be found in IBM “Model B” keyboards or more commonly known as “IBM Beam spring” keyboards.
TL;DR
Unlike most switches, beam springs don’t have an equivalent alternative – there are no other keyboards that have beam spring switches, so these are a one-a-kind.
However, they are one of the best switches ever made. They’re very smooth and perfectly weighted! Sure, they could do with being more consistent, but I don’t exactly have the cleanest example on-hand. Plus, its age probably played a factor in its current performance. I don’t doubt a brand new one would perform exceptionally well.
Additionally, it’s worth pointing out that beam spring keyboard reproductions are currently being made by Model F Labs. These don’t have an ETA as of writing this review, but once they release, they’ll be the only alternative to IBM Beam spring keyboards.
Smoothness: 7/10
On-centre keypresses are very smooth with only some binding on slow keypresses.
Off-centre keypresses aren’t as smooth with more noticeable binding on more keys at slower keypresses.
Overall, given their age, these are still smoother compared to many modern switches. I can only imagine how these were like brand new.
Weighting: 10/10
Now, according to IBM these switches have an actuation force of 55g around 2.5mm, a total travel of about 3.8mm and resets around 1.0mm.
IBM Beam spring force curve.
The above shows a force curve of the IBM Beam spring.
IBM Beam spring consistency force curve.
As you can see from the above, they aren’t very consistent. On the downstroke, all 3 switches have slightly different weightings, especially after actuation. Although, the upstroke was a little bit more consistent with the reset point being roughly at the same distance.
IBM Beam spring vs. IBM Capacitive Buckling Spring force curve.
The above force curve shows a comparison between the IBM Beam spring and its successor – the IBM Capacitive Buckling Spring. They show very different weightings as they are completely different clicky switches, but I thought it would be nice to see the differences between the two as I really like them both.
IBM Beam spring vs. Cherry MX Blue force curve.
The above force curve shows a comparison between the IBM Beam spring and the Cherry MX Blue. These two are again, very different clicky switches. But since there are currently no direct beam spring alternatives, I thought I’d compare them to a very well-known Cherry clicky switch.
Overall, despite the inconsistencies, they feel super consistent in the real world and I absolutely love their weighting. I now have high expectations for the upcoming reproductions.
Sound: 9/10
In some beam spring keyboards, you get two options – solenoid on or solenoid off. Unfortunately, the solenoid on my model was a little faulty, so I couldn’t enjoy it to its full extent.
Either way, I really like how they sound. They have a very unique sound signature which I find hard to describe. I suggest you take a listen to my typing demo.
Overall, they would be a perfect 10, but they have a bit of ping which I dislike. Although, the solenoid masks this, so take your pick.
Typing Performance: 10/10
I’ve always enjoyed typing on beam spring switches. Their smoothness combined with their weighting is as close perfection as you can get.
Their consistency may look like they’re all over the place, but this isn’t the case in the real world. Once you start using the switches, you’ll likely forget about the force curves.
Overall, if it wasn’t for the uncomfortable typing angles the Model Bs are known for, I would 100% use these more often. As a side note, I would build a beam spring keyboard in a 60% form factor if I could. And I wish I could.
Gaming Performance: 6/10
Gaming probably wasn’t anywhere near IBM’s mind when they were designing this keyboard.
Firstly, as I’ve hinted, Model Bs are known for having really high typing angles which make it hard to use these switches for lengthy periods as great as they are.
Secondly, these switches have an insane hysteresis. They actuate around 2.6mm and reset around 1.2mm which means they roughly need to travel 1.4mm to reset before they can be actuated again. For a switch with a total travel of around 3.6mm, this is a lot, and many gamers will feel that these switches are “too slow”.
Finally, I need to reiterate that I couldn’t fully use these for gaming as the conversion on my IBM 5251 was incorrectly done, so my score is mainly based on what I think the performance will be.
Overall, it’s obvious it wasn’t made for any kind of serious gaming, but they’re serviceable for light and casual gaming – which some modern switches can’t boast about.
Final Score = 42/50 (84%)