Where the Saru Started
The original Saru launched around 2021 when short-travel tactile switches were still rare. At the time, the idea of pushing pre-travel down and sharpening the bump was unconventional.
Since then, the hyper-tactile market has grown significantly. Switches like the Siliworks Type R, HMX Black Cat, and HMX Retro J now occupy a similar space in terms of travel distance and responsiveness. So rather than re-release the original, we set out to build something new. A modernized Saru that we would genuinely enjoy using ourselves.
What's Behind the HMX Saru V2
We built Saru V2 around three things we refused to compromise on:
- Ready out of the box. No tuning, no re-lubing, no extra work required.
- Built for long sessions. Full tactile feel without the finger fatigue.
- Pleasant and balanced sound. Not too sharp, not hollow. Just clean.
We also gave ourselves one extra challenge during development.
What would a full tactile switch feel like if we tried to make it feel like a linear?
That question shaped everything.
HMX Saru V2 Specifications
- Top Housing: PA12 Nylon
- Bottom Housing: PA2 Nylon
- Stem: Modified POM
- Spring: 20mm KOS Stainless Steel
- Actuation Weight: 48±5g
- Bottom-out Weight: 52±5g
- Pre-Travel: 2.5±0.5mm
- Total Travel: 2.9±0.3mm
- Lube: Modified factory application
- Manufacturer: HMX
Sound Profile: Clean, Balanced, Clacky, Semi-full
How We Built It
We've handled a ton of switches. Different brands, different types, every new internal mechanic you can think of. So instead of adding another gimmick, we went back to basics:
- Known, high-quality materials
- Intentional switch design
- Great sound and feel out of the box
HMX embodied all three, so we reached out. After talking with the owner, we landed on a plan to start with one of their existing molds and expand from there. Their Retro J came closest to what we had in mind, and after a few rounds of back and forth on the vision, we were ready to prototype.
Prototype Round 1
Two things stood out immediately. The top housing color was off. We wanted a more saturated take on the original Saru, and we had grabbed the wrong pantone. Easy fix.
The feel, though, was already right. The problem was a ping we couldn't identify. We swapped springs, housings, and stems, but nothing killed it. Turns out the stem we had designed had thinner legs than HMX's usual stems, which weakened the contact with the leaf just enough to let that noise through.
Prototype Round 2
Color came back exactly right. The backup pantone was the one.
After providing feedback and brainstorming with HMX, we made two key changes:
- Reworked the lube application to the stem, bottom housing, and spring
- Reduced the stem leg angle by 2 degrees, which strengthened the contact with the leaf just enough to quiet the majority of the ping. It also made the tactility feel noticeably lighter, around 2 to 3g
The tactility came out lighter than the original, but it landed a lot closer to what we were after. Although the majority of the ping was gone, we wanted to see how close we could get to ping-less.
Final Round + Production Units
After HMX received our feedback, they went back to the drawing board and fine-tuned the lube application method. They tested a few changes and found that a more targeted lube application might help resolve the issue as reducing the stem angle already did most of the heavy lifting.
Thankfully, they got it right.
When we finally received the latest round, we found that the final lube technique resulted in significantly more consistent switches in both sound and feel. It also nearly solved the ping issue. This new lube technique is now being utilized as their standard for factory lubrication.
One thing we did notice was that the tactility felt slightly different than version 2. Out of the box, the switch still retained full tactility BUT it felt slightly heavier at the top. After a break-in period and the targeted lube becoming more evenly distributed, the switch reverted to the original light-full tactility from prototype 2 (except without the ping).
What It Sounds and Feels Like
Saru V2 puts a full tactile bump right at the very top of the keystroke. If you're not actively paying attention, you may forget it's even tactile. The moment you remember, you'll feel it every time.
Most of us are linear users (kbd.news' top 10 switch list runs about a 7:3 split), so we wanted a switch that felt familiar enough for linear users while staying true to full tactile enjoyers. It's a full tactile with a light bump that almost feels like a linear.
Tactile in the front, linear in the back.