Sol 3 is RGBKB's first keyboard to feature our new mounting system, the R-Mount.

The R-Mount system is a new case design methodology that builds upon the very best this community has to offer. It features the following:

  • Gasket-mount Switchplate & PCB
  • MX & Choc compatibility
  • Magnetic, screwless assembly option
  • Plateless option

 - Design

The driving force for the R-Mount design is mirrored geometry. Excluding the PCB, all case parts are reversible between left and right halves. This reduces development costs, and increases volume discounts during production runs. The medium-profile height allows RGB switches to show off. 

 - Gasket-mount

Gaskets are mounted to the switchplate and PCB. Switchplates use a standard size O-ring, AS568 010. PCB gaskets use a molded part. Since gaskets fit over tabs and fit into slots, there is no need for adhesive.

The user may choose to omit the mounts on either the switchplate or PCB, to adjust the typing feel. Plateless builds simply require removing the switchplate.

 - Lighting

RGB is a critical feature for RGBKB. Polycarbonate middle frames can take advantage of reverse-mount LEDs, oriented in the same direction as backlighting. The light path for perimeter LEDs is optimized for diffusion. Underglow is available through optional pogo-pin daughterboards.

 - Magnetic Assembly

R-Mount allows for either magnetic or M2.5 screw assembly. By using steel top & bottom plates with magnets, the case can be assembled without screws. Bottom plates may also have cutouts for magnetic tenting feet.

 - Materials

Laser-cut top & bottom plates help reduce cost. Steel must be used with magnets, either 400-series stainless or painted carbon steel. For nonmagnetic plates (carbon fiber, FR4, aluminum), M2.5 screws with standoffs can be installed.

Only one machined/molded part is required per half, the middle frame. Polycarbonate or Acrylic can be used for RGB glow, with injection-molded diffusion PC giving the best results. For a more professional look, machined aluminum may be used.

 - Compatibility

MX-Style switches are the primary focus for R-mount. Choc switches may be used with standard cases, but can only be gasket-mounted through the PCB.

 - Disadvantages

The middle frame cannot be removed from soldered builds after assembly.

High-flex, plateless PCBs may bottom out on the bottom plate. Trimming switch pins, or modifying the base design specs, is recommended for this setup.

Creating angled cases without a gap is difficult. Case height above the switchplate can be 3-4mm, higher will require more CNC'd parts.

 - Free to use

A design guide will be made for other keyboard designers to use, under the Creative Commons - Attribution 3.0 license. To be available by July 2021.