Hello mechanical keyboard enthusiasts! After almost a year of learning, research and development, I am proud to present to you the Duo-S, a passion project which I hope will spur innovation in this community.
Duo-S
Duo-S (S stands for small) was conceptualised around an optimised mounting solution for hotswap PCBs (more details below) and has a 65% layout. It is designed to be minimalistic and clean but yet provide a rich experience. Allow me to share with you some of the key features and design considerations of this board.
Features and Design Considerations
Duo Mount: The highlight of this board that gives it its name! This board uses a dual gasket/isolation mount arrangement for the plate as well as PCB. The key inspiration leading to such a solution came from the desire to eliminate the use of standoffs for hotswap PCBs. With gaskets supporting the PCB from below at strategic spots on its perimeter, standoffs will not be required. That being said, switch swapping will have to be done in an alternate fashion (i.e. recommended only to remove 50% of switches at a time when swapping). This has been tested on the prototype and works really well!
The Duo mount arrangement engages both the plate and hotswap PCB for dual support. This contributes to a grounded but comfortable bottom-out feel. In addition, softer plate materials can be used (if desired) at standard 1.5mm thickness without causing the typing feel to be too squishy because the PCB is also gasket-supported. Overall, this balanced arrangement makes for a pleasant typing experience.
Acoustic Frame: The plate will rest on gaskets mounted on a brass acoustic frame. The weight balance (i.e. center of gravity) of the board has been brought up to the middle layer (unlike traditional bottom weighted boards) to allow vibrations to be channeled directly into the dense brass material for maximum vibration diffusion. This allows for clean acoustics and a grounded typing experience despite the board’s average overall weight. The brass acoustic frame also provides a nice aesthetic skirting at the bottom of the top case.
Triple Material: The board is a combination of an aluminium top case, middle brass acoustic frame and a polycarbonate (PC) bottom case. This enables us to enjoy the benefits that all materials bring to the table. The aluminium top case is favoured for its durability and colourability, the dense brass frame for its ability to diffuse vibrations and the PC bottom case for its lower pitch sound signature (as a “sound box”) and its translucency for lighting effects. This idea is not new but I would have liked to see more customs offering such a combination
3M Rubber Gaskets: After testing both 3M rubber and Poron gaskets, I have found that the 3M rubber provides for a subjectively lower pitch sound. This could be due to the way a stiffer gasket absorbs vibrations. Also, a stiffer and grippier gasket is more ideal for hotswap arrangements due to the forces from switch swapping experienced while the plate is mounted in place.
Uniform Bezels: One of the key design principles for this board was to have a uniform 0.5U bezel throughout. This is evident not only on the top case, but also from the underneath.
Cove Lighting: Underglow cove lighting peeking out from the top and sides of the board is made possible with a PC bottom case. Refined and subtle.
Hotswap PCB: The hotswap PCB will be produced by trusted PCB maker DZ and will include key features such as ESD protection, underglow lighting and VIA compatibility. It will only come in one configuration, but you’ll be happy to note that the KBD67 MKII PCB (hotswap/soldered) is compatible with this board
Alignment Strips: This is not a board feature per se, but to solve the age-old alignment problem (for gasket mount boards that do not have internal alignment features), alignment strips have been designed to remove the guesswork required and to aid the installation of screws on the bottom case.
Other Details
- 7 degree typing angle - Brass/FR4 plate options - Custom 3M rubber gaskets - Top case: 6063 aluminium in anodized black/steel grey/marine navy/e-white (only top 3 voted colours will be selected) - Bottom case: Sandblasted PC - Estimated weight (fully built): ~1.2kg - Price: SGD499/~USD385, all platform fees included but excluding shipping/any local taxes - Additional plate/PCBs allowed for order - Quantity: 300 units - GB period: 30th May, Sunday, 11pm SGT (GMT+8) / 11am EST (GMT-4) - GB method: www.duofoundry.com, FCFS
FAQ(more to be added along the way)
1. Where are you based and who are you working with?
I am based in Singapore and have taken up this project in collaboration with a good friend who is based in China. We have day jobs but this is a project that we take seriously and certainly hope to grow into something bigger
2. Why should we trust you since this is your first time?
We are certainly new in the area of custom keyboard making and have learnt so much in the past year! The journey thus far has had its ups and downs and we decided not to launch an IC unless we had satisfactory prototypes on hand. At this stage, we have already gone through more than 3 rounds of prototyping and elimination of manufacturers that could not meet the quality requirements. As of now, we are very happy with the latest prototypes. We are also fortunate to be working with factories that have produced popular boards for the community. With this confidence, we are going ahead as planned and will strive to deliver a premium product. The quantity is intentionally kept low as we would like to manage the QC process more closely.
We also view this as a long-term relationship with community members and do wish to expand the Duo offering with your support (hint: Duo-M, Duo-L)
3. Will Duo-S be sent to a streamer for review?
We certainly have plans to send our prototype out for review. Stay tuned for more news on this.
4. Any plans for a Discord channel?
We may consider setting one up closer to the GB date but otherwise, follow our instagram @duofoundry for the latest updates.
IC Disclaimer
Kindly note that the information contained in this IC is subject to change and will only be finalized during the GB.
Feedback
We would be really happy if you could let us know your thoughts/feedback/suggestions via reply on this thread/filling in the IC form
1. Fill in the IC form, we would really like to gather your valuable feedback 2. Follow @duofoundry on Instagram to get the latest updates 3. Subscribe to email updates on www.duofoundry.com. Create an account beforehand if you wish to participate in the GB (you will need an account to purchase) 4. Revisit this thread to keep in touch with the general progress
Prototype Pictures
Steel grey prototype:
Navy and Black prototypes:
FR4 and Brass plate:
PCB made by DZ:
Sound Test:
Lubed and filmed Alpacas, brass plate, EPBT keycaps
Lubed and filmed Lilacs, FR4 plate, EPBT keycaps
BONUS Release
Duo Peg
Sick and tired of how the current switch pullers get all bendy don’t seem to work? Together with the GB, the Duo Peg will also be released for sale. These will be an in-stock purchase but there are only 60 pieces available for the first run. Rest assured, more will be produced in the future if there is keen interest.
After countless rounds of redesigning, prototyping and testing, I have concluded that FDM 3D printing will be the most suitable way to produce the Duo Peg. In addition to keeping the price down for the community, using plastic as opposed to metal will prevent damage to your plate.
Material: Carbon Fiber PETG. This material is more tricky to print compared to the standard PLA. However, it is one of the stiffest materials for 3D printing and offers the structural stability required for this tool. I have also tried SLA and MJF methods of 3D printing. Although they offer a better surface finish, based on testing, the thinner portions of the Duo Peg tend to break a lot more easily (although the material used has higher tensile strength on paper). I suspect this is due to the method of fusing the material for which FDM seems stronger for thinner implementations.
Design: Resembling the look of a clothes peg, the Duo Peg uses a 1st class lever design as opposed to a 3rd class lever on the standard switch puller. This reduces the amount of effort the user needs to have a firm grip on the switch. Also, there is a limit to which the Duo Peg can be compressed in order to prevent damaging the switch and the tool itself.
The Duo Peg will be sent to a streamer for review as well, stay tuned!
Price: S$25/~US$20, shipping not included In-stock Purchase Date: 29th May, Saturday, 11pm SGT (GMT+8) / 11am EST (GMT-4)
Thank you for reading this long IC! Remember to fill in the IC form and hope to see you in the GB
![Duo-S - 65% Duo Isolation Mount [GB Date: 30 May 2021]](/_next/image?url=https%3A%2F%2Fi.imgur.com%2FC8jiaCZ.png&w=3840&q=75)
