Home / Reference / Switch and stabiliser cutout dimensions
Switch and Stabiliser Cutout Dimensions for Keyboard Plates
A Cherry MX switch sits in a square hole of 0.551 in (13.995 mm) with a tolerance of plus or minus 0.002 in (0.051 mm). The stabiliser slots are wider than they look and their spacing depends on the key length. The values below are the numbers Cherry prints, converted to millimetres.
Edition: a Cherry MX Series keyswitch datasheet, pages 10-3 and 10-4, inches, undated copy. Checked October 2026. We are a matching service, not a machine shop, and these are planning values for a drawing, not a promise from any shop.
Switch hole and plate
| Dimension | Value, in | Tolerance, in | Value, mm | Tolerance, mm | Note |
|---|---|---|---|---|---|
| Switch hole, each side | 0.551 | ± 0.002 | 13.995 | ± 0.051 | Square hole in the metal frame (plate). The stabiliser drawings print the centre square as 0.55 ± 0.002 in, so use 0.551 from the single-switch drawing. |
| Corner radius of the hole | R 0.012 max | maximum | R 0.30 max | maximum | A milling cutter leaves a corner radius at least as large as its own radius, so this limit sets a cutter of about 0.6 mm diameter or smaller (our arithmetic). |
| Plate (metal frame) thickness | 0.06 | ± 0.004 | 1.52 | ± 0.10 | Dimension shown beside the cutout view, next to two DIN 6784 edge labels (D2, C3). We did not read DIN 6784. |
| Plate top to PCB top | 0.197 | + 0.012 | 5.00 | + 0.30 | From the mounting options drawing, metal frame (without pins) version. Printed with a plus tolerance only. |
Source: Cherry MX Series keyswitch datasheet, pages 10-3 (mounting options) and 10-4 (metal frame cutout dimensions), a copy hosted at cdn.sparkfun.com. Millimetre values are our conversion, rounded.
Stabiliser slot
| Dimension | Value, in | Tolerance, in | Value, mm | Tolerance, mm | Note |
|---|---|---|---|---|---|
| Width of each stabiliser slot | 0.262 | ± 0.004 | 6.65 | ± 0.10 | The same value appears on the 2u drawing and on the 3u to 10u drawing. A Deskthority poster gives the same width as 6.65 mm. |
| Overall slot height | 0.53 | ± 0.006 | 13.46 | ± 0.15 | Printed on the right side of both drawings, the longer of the two vertical dimensions there. |
| Slot height to the step | 0.484 | ± 0.004 | 12.29 | ± 0.10 | The shorter of the two vertical dimensions on the right side, measured to the step in the slot. |
| Lower ear width | 0.12 | ± 0.004 | 3.05 | ± 0.10 | Printed under the lower step of the slot on both drawings. |
| Step offset (left side) | 0.11 | ± 0.008 | 2.79 | ± 0.20 | Printed on the left of both drawings. Looser than the other stabiliser values. |
| Other dimensioned values | 0.166 / 0.165, 0.26, 0.032, 0.031 | ± 0.004 | 4.22 / 4.19, 6.60, 0.81, 0.79 | ± 0.10 | Position and notch values. Read their positions on the datasheet drawing (page 10-4) before you draw them. |
| Corner radius of the slot | R 0.012 max | maximum | R 0.30 max | maximum | Printed several times on the stabiliser drawings, the same limit as the switch hole. |
Source: the same datasheet, page 10-4, drawings for keycap sizes 1 x 2 to 1 x 2.75 and 1 x 3 to 1 x 10. The datasheet prints dimensions without naming each one in words, so the notes describe where each value sits on the drawing. Millimetre values are our conversion.
Stabiliser centre spacing by key size
| Keycap size, u | A, in | A, mm |
|---|---|---|
| 1 x 2, 1 x 2.25, 1 x 2.75 | 0.94 | 23.88 |
| 1 x 3 | 1.5 | 38.10 |
| 1 x 7 (cylindrical keycaps) | 4.5 | 114.30 |
| 1 x 8 (standard keycaps) | 5.25 | 133.35 |
| 1 x 8, 1 x 9, 1 x 10 (cylindrical keycaps) | 5.25 | 133.35 |
Source: Cherry MX Series datasheet page 10-4, the leveling mechanism kits table (row A in inches). The datasheet has no entry for 1 x 6.25 keys, so we give no figure for them.
How to read the tables
The switch hole is the one dimension every plate has to get right. The datasheet allows plus or minus 0.002 in, which is 0.051 mm either way, so the whole band is about 0.10 mm wide. A Deskthority poster reports that European Cherry datasheets state the same hole as 14 plus or minus 0.05 mm with a corner radius of 0.3 mm maximum, and that US datasheets use converted inch values. We could not open the European datasheet.
The stabiliser values are the part people get wrong, because the slot is not a plain rectangle. It has a step, ears and several small dimensions, so redraw it from the datasheet or from your supplier’s file rather than from memory. In one Deskthority thread a poster found a community file with the slot width at 6.75 mm against 6.65 mm in the Cherry figure; another poster reported that a laser-cut steel plate from that file worked, with stabilisers needing a little force to mount. Treat that as one report, not a rule.
Common mistakes
- Drawing the hole to nominal and ignoring the finish. Wikipedia states that in typical commercial anodising each surface grows by half the oxide thickness. A 20 micrometre film therefore takes about 0.02 mm off the hole width (our arithmetic), about a fifth of the 0.10 mm band. Say on the drawing whether the cutout dimension applies before or after finishing.
- A corner radius the cutter cannot make. A 0.30 mm radius limit means a very small cutter, a slow cut and, on a deep plate, a fragile tool. Some designs add relief notches at the corners instead. Ask the shop which they prefer.
- One tolerance for every cutout. The stabiliser step carries plus or minus 0.2 mm in the datasheet while the switch hole carries about 0.05 mm. Giving every cutout the tight value prices the whole plate for one feature.
- Mixing stabiliser types. This datasheet covers Cherry’s own metal frame cutout. Deskthority describes Cherry-style plate-mounted, Costar-style plate-mounted and Cherry PCB-mounted stabilisers. We did not find a Costar cutout drawing we could open, so none is given here.
What to write on the drawing or RFQ
- The switch family and the datasheet edition the cutouts come from.
- The hole size and tolerance as a separate callout, with a note on whether it applies before or after anodising.
- The stabiliser type and the keycap sizes that need one.
- The plate thickness and its tolerance, and a flatness callout if the plate must sit flat.
The reasoning behind callouts is in which tolerances actually matter and in what to put in a CAD package. If you want shops to quote the plate, send an RFQ.
Not read: the current cherry.de datasheet, the European edition, DIN 6784, any Costar stabiliser drawing, and any shop’s own cutting limits.