The Reflexion Grid - The adaptable keyboard

Features

The Reflexion Grid is the perfect keyboard if you want a slimmed, small outline ortholinear keyboard. With it's full size, having 70 keys split in two 5x7 hands, it equals a 65% keyboard in number of keys. Break of the bottom row, or either of the two outer columns, or all of them at once, and you can have a 50%, a 40% or a 30% keyboard instead. Changing the size is as easy as breaking of the parts you want to remove and cleaning up the edges, and then doing the same to the plates and it all works just as before. (And no, you can't do the reverse... Sorry...)

Adding an optional OLED and Rotary Encoder (with multiple placement options), for each hand, you have plenty of options to customize it and make it your own. Then adding the option of full per-key RGB to that, and you have plenty of bling and color if you like that.

With an RP2040 MCU and 2MB of on-board flash, you should have all the memory needed for advanced keymaps and/or RGB effects galore.

The Grid is fully hotswap capable, and can be delivered as a ready to use keyboard or as a kit to build yourself. It supports the full 1u grid in all sizes, or it can be built with an inner 2u thumb key on the bottom row . Adding the OLED, encoder or 2u keys requires some basic soldering, and in the case of the OLED, removing a tab on the front plate, so a tiny bit more work, but still quite beginner friendly.¹

Main Features:

• QMK and VIAL compatible, fully programmable keyboard
• RP2040 MCU, Dual-core Arm Cortex M0+ processor, flexible clock running up to 133 MHz
  • 264 KB of SRAM, and 2+ MB of on-board Flash memory (max 64 KB adressable in QMK/Vial) ²
  • USB-C connector to host computer, (USB 1.1 device and host support)
  • Low-power sleep and dormant modes
  • Drag-and-drop programming using mass storage over USB
• Kaihl hot-swap sockets for Cherry MX compatible switches (3 & 5-pin) ³
• USB-C Full duplex serial link (Uses USB 2.0 compatible cable)
• Full ESD protection on both USB host and Serial link connection (SRV05-4)
• Fully reversible PCB & Plates, identical for both hands
• Designed with a Sandwich-style plate/case as part of the design
• Six main layouts:
  • 4 x 5 - 36-40 keys
  • 4 x 6 - 44-48 keys
  • 4 x 7 - 48-54 keys
  • 5 x 5 - 46-50 keys
  • 5 x 6 - 54-60 keys
  • 5 x 7 - 66-70 keys
• Physical dimensions (LxBxH): 2 pcs AAA x BBB x CCC mm

Optional add-ons:

These options requires additional components not included in this listing and sold separately.

• OLED Screen - One per hand, takes up the space of two 1u keys.
• Rotary Encoder - 1 per hand, replaces one 1u key.
• Per key RGB - 36 to 70 RGB LED's depending on configuration
• RGB Indicator/Logo - Uses 3 RGB LED's

Note - Use SK6803 Mini-E ONLY for all RGB!!! ⁴

Build Features:

• Reversible PCB design, identical options for both sides.
• Full build instructions printed on the PCB for an easy build.
• Smaller SMD components (RP2040 MCU, Flash memory & supporting components) are always fully pre-soldered and tested.
• Larger SMD components (HotSwap Sockets) are user mountable, and suitable for a beginner to solder.
• Optional parts (OLED, RGB & Rotary encoders) are user mountable, and suitable for a beginner to solder.

Assembly

Little or no tools at all needed! The PCB can be delivered fully built and ready to use, with all the options of OLED's/Encoders/RGB you prefer. This requires added components to be purchased along with the PCB!!!

Or as a basic Barebones Keyboard with no OLED/Encoder/RGB added, and no need to solder anything unless you want to add these yourself. This way the keyboard is ready to use as is, but can easily be customised to your needs with little need for skilled soldering.

Or if you prefer, as a "DIY-Kit" with soldering needed. In this case, all you really need to solder for a functional keyboard is the hotswap sockets, and any OLED's/Encoders/RGB you want to add, so it's very simple for a beginner to start learning. Other parts like the MCU and it's supporting components, as well as the USB ports, are already completed & tested.

Adding OLED's and Encoders to the PCB for both the barebone's option and DIY-Kit, is also fairly basic soldering with larger through hole components, and very well suited for a beginner wanting to learn.

The optional RGB LED's needs to be soldered in place if used. These are a tiny bit more advanced than the other parts being somewhat sensitive to overheating, but being winged, with the soldering and heating taking place 'outside' the main body, they are more than possible for a beginner to solder with some care and patience.

To change the size, you need an exacto knife to score the material, maybe a pair of pliers to save your fingers and a file or sandpaper to remove the sharp edges. To assemble the plates you will need a hex head screwdriver, for the spacers & bolts. (Size H1.5)

The Sandwich Case

The Reflexion Grid is designed as a complete keyboard with a sandwich style case

The FR4 fibreglass plates used are quite stiff and give a good intermediate feel for keyboards, making it the ideal low cost material for a case. The PCB comes with the case plates as part of the kit, and you select the color and if you want an OLED or not on each hand.

The 'case plates' are available in (black or) white, with either a full 1u upper shield, and with the option to break off a tab for the OLED, based on your choice. The most 'average' option is probably to choose one single OLED, as you rarely have a need for more than one screen. But if you want too, you can certainly have one on each hand, and although you probably need no more than one, up to three encoders per hand as well.

For now, there is no 3D printed case designed. I'm not the worlds best 3D designer myself. But if you want to make a case for this keyboard you are more than welcome too, 3D files (.STEP) of the PCB will be available to start from. And I will most certainly link & credit any designs from the GitHub pages, for other users to print.

What's in the Kit?

The DIY-Kit and prebuilt contain the exact same components.

Included Components

Required Accessories

These are the parts you need to complete a usable, working keyboard

• Key Switches, Cherry MX compatible (up too 70 pcs)
• Key Caps, Cherry MX compatible (Set)
• Serial link cable - USB type C/C (USB 2.0 standard)
• Cable to your computer (USB type C/C or C/A)

Credits

This design was created by 'TweetyDaBird' Markus Knutsson, with a concept and continuous input from 'The Reflex' Pedro Quaresma, although with a fair amount of liberty taken accounting for hardware constraints.

¹ To insert or remove the stabilizer you will however have to remove the keys and split the plates apart.

² Depending on parts availability, this can be delivered with a 2/4/8 MB FLASH EEPROM. QMK's base code can directly adress no more than 64 KB, and for wear leveling purposes this uses 64 KB of RAM/SRAM)

³ Please note that The Reflexion Grid supports only Cherry MX type switches (3 & 5 pin), NOT Kaihl Choc, as they require a different PCB and plate design.

⁴ With the number of RGB LED's this PCB can support, it can easily overpower the USB ports ability to deliver power if SK6812 Mini-E type RGB are used, and can ultimately cause damage to the port in extreme cases. Please use ONLY SK6803 Mini-E, to keep power consumption at a somewhat sane level.

Normal handling time is 3-5 working days, not including build items (Those usually take 1-2 weeks). I normally process orders on the weekend, as this is in-fact not my full time job.

Shipping is done with insured/signed for parcels, where no such service is available the parcel is sent as insured parcel, but may not be fully traceable the entire transit. If no insured or traceable service is available, parcels will be sent as uninsured/untraceable at the buyers responsibility.

All packets are represented to courier services and customs at their true value, and all responsibility for import fees, taxes and tariffs resulting there of lies with the buyer.

The SE "Act on Distance Contracts and Off-Premises Contracts" (SFS 2005:59) & The EU "The Distance Selling Directive" (97/7/EC) allows returns of the items initiated within 14 days of receiving it. Shipping of returned items is the sole responsibility of the buyer.

(Please note that in the case of kits as is mainly sold here, this does no longer apply once you start soldering/building the kit as it is then no longer in it's original condition, and you have at that point explicitly accepted the purchase contract!)