The thyme keyboard#

More deets coming soon 👀#

A split, low-profile, wireless mechanical keyboard inspired by the Corne design. Made possible through the hackpad grant from Hack Club.

BOM#

Part	Quantity	Price	Link	Description	Notes
SuperMini NRF52840 (Nice!Nano footprint)	2	`$4.15`	AliExpress	Wireless Microcontroller
Machine Sockets 2.54mm	1	`$1.75`	AliExpress	26x2 needed to socket the two MCUs	comes in a 10 pack of 40x1 rows
Machine Pins	1	`$3.99`	AliExpress	26x2 needed to socket the two MCUs	comes in a 100 pack of 4 per header
Power Switch	4	`$0.39`	DigiKey	one for each half	added an extra switch for each side as backup
JST PH 2.0mm 2-pin Connector	4	`$0.10`	DigiKey	for battery connection
301230 3.7V 110mAh LiPo Battery	2	`$6.30`	AliExpress	comes pre jst ph-ifised	two lot
PCB	1	`$25.15`	JLCPCB	2-layer, 1.6mm, black, leaded Hasl	I wanted to get ENIG but that bumped the price by `$20`
Diodes	42	`$1.43`	DigiKey	1N4148
Choc v1 switches	50	`$27.50`	Chosfox	pink variant: `20+-5 gf` linear
1u keycaps	40	`$14.00`	Chosfox	White PBT low profile
1u homing keycaps	2	`$0.80`	Chosfox	White PBT low profile
1.75u keycaps	2	`$1.65`	Chosfox	White PBT low profile

Total cost: $85.11

Store breakdown#

Store	Shipping	Subtotal	Total	Items
AliExpress	`$9.43`	`$26.64`	`$36.07`	2x SuperMini NRF52840, Machine Sockets, Machine Pins, 2x LiPo Battery
DigiKey	`$6.99`	`$4.49` (tarrifs and tax)	`$11.48`	4x Power Switch, 4x JST Connector, 42x Diodes
Chosfox	`$5.00`	`$43.95`	`$48.95`	50x Choc v1 switches, 40x 1u keycaps, 2x 1u homing keycaps, 2x 1.75u keycaps
JLCPCB	`$10.55`	`$14.60`	`$25.15`	1x PCB

Total shipping: $31.97
Total cost: $122.67 (including shipping, tax, and tarrifs)

Schematics#

schematic

pcb

Build Notes#

Panelization is the most annoying bit of this whole process. I was able to finally get it work work by using kikit to generate rails and tabs.

kikit panelize \
    --layout 'grid; rows: 1; cols: 1; space: 3mm;' \
    --tabs 'fixed; width: 3mm; vcount: 8;' \
    --cuts 'mousebites; drill: 0.5mm; spacing: 1mm; offset: 0.2mm; prolong: 0.5mm;' \
    --framing 'railstb; width: 5mm; space: 3mm; chamfer: 1mm;' \
    --tooling '3hole; hoffset: 2.5mm; voffset: 2.5mm; size: 1.5mm;' \
    --fiducials '3fid; hoffset: 5mm; voffset: 2.5mm; coppersize: 2mm; opening: 1mm;' \
    --post 'millradius: 1mm;' \
    --text 'simple; text: "THYME v1.14"; anchor: mt; voffset: 2mm;' \
    --text2 'simple; text: Created on {date} JLC Order: JLCJLCJLC; anchor: mb; voffset: -2.5mm; hjustify: center; vjustify: center;' \
    thyme.kicad_pcb panelization/panelized.kicad_pcb

panelized