# Tab washer (DIN 93, DIN 463)

Tab (lock) washers as delivered, flat: DIN 93 with one long tab, DIN 463 with a long and a short tab at right
angles, M3 to M52, with catalogue sizes as presets.

## Geometry

A disc of outside diameter **d2** with the hole **d1** and thickness **s**. The long tab, width **b**, reaches **l**
(DIN 93) or **l1** (DIN 463) from the hole's centre along +X; DIN 463's short tab, also width b, reaches **l2** along
+Y. The tabs' corner radius **r** is not modelled. The washer lies on the XY plane at the origin, its thickness along
+Z.

## Parameters

| Parameter | Meaning |
|---|---|
| `standard` | `DIN 93` (long tab), `DIN 463` (long and short tab) |
| `size` | Thread size, M3 to M52 |
| `material` | `steel` (soft, formable), `stainless-a2` |

## Sources

Tables read from the reproductions on fasten.it (mm), checked against fasteners.eu for M4 to M39.

### DIN 93:1974-07, tab washers with long tab

<https://fasten.it/norms/norm/din_93>; <https://www.fasteners.eu/standards/DIN/93/>.

| Size | d1 | d2 | b | l | s |
|---|---|---|---|---|---|
| M3 | 3.2 | 12 | 4 | 13 | 0.38 |
| M3.5 | 3.7 | 12 | 4 | 13 | 0.38 |
| M4 | 4.3 | 14 | 5 | 14 | 0.38 |
| M5 | 5.3 | 17 | 6 | 16 | 0.5 |
| M6 | 6.4 | 19 | 7 | 18 | 0.5 |
| M7 | 7.4 | 19 | 7 | 18 | 0.5 |
| M8 | 8.4 | 22 | 8 | 20 | 0.75 |
| M10 | 10.5 | 26 | 10 | 22 | 0.75 |
| M12 | 13 | 30 | 12 | 28 | 1 |
| M14 | 15 | 33 | 12 | 28 | 1 |
| M16 | 17 | 36 | 15 | 32 | 1 |
| M18 | 19 | 40 | 18 | 36 | 1 |
| M20 | 21 | 42 | 18 | 36 | 1 |
| M22 | 23 | 50 | 20 | 42 | 1 |
| M24 | 25 | 50 | 20 | 42 | 1 |
| M27 | 28 | 58 | 23 | 48 | 1.6 |
| M30 | 31 | 63 | 26 | 52 | 1.6 |
| M33 | 34 | 68 | 28 | 56 | 1.6 |
| M36 | 37 | 75 | 30 | 60 | 1.6 |
| M39 | 40 | 82 | 32 | 64 | 1.6 |
| M42 | 43 | 88 | 35 | 70 | 1.6 |
| M45 | 46 | 95 | 38 | 75 | 1.6 |
| M48 | 50 | 100 | 40 | 80 | 1.6 |
| M52 | 54 | 105 | 44 | 85 | 1.6 |

### DIN 463:1974-07, tab washers with long and short tab at right angles

<https://fasten.it/norms/norm/din_463>; <https://www.fasteners.eu/standards/DIN/463/> (no d2).

| Size | d1 | d2 | b | l1 | l2 | s |
|---|---|---|---|---|---|---|
| M3 | 3.2 | 7 | 4 | 13 | 5 | 0.38 |
| M3.5 | 3.7 | 8 | 4 | 13 | 5.5 | 0.38 |
| M4 | 4.3 | 9 | 5 | 14 | 6.5 | 0.38 |
| M5 | 5.3 | 10 | 6 | 16 | 8 | 0.5 |
| M6 | 6.4 | 12.5 | 7 | 18 | 9 | 0.5 |
| M7 | 7.4 | 14 | 7 | 18 | 10 | 0.5 |
| M8 | 8.4 | 17 | 8 | 20 | 11 | 0.75 |
| M10 | 10.5 | 21 | 10 | 22 | 13 | 0.75 |
| M12 | 13 | 24 | 12 | 28 | 15 | 1 |
| M14 | 15 | 28 | 12 | 28 | 16 | 1 |
| M16 | 17 | 30 | 15 | 32 | 18 | 1 |
| M18 | 19 | 34 | 18 | 36 | 20 | 1 |
| M20 | 21 | 37 | 18 | 36 | 21 | 1 |
| M22 | 23 | 39 | 20 | 42 | 23 | 1 |
| M24 | 25 | 44 | 20 | 42 | 25 | 1 |
| M27 | 28 | 50 | 23 | 48 | 29 | 1.6 |
| M30 | 31 | 56 | 26 | 52 | 32 | 1.6 |
| M33 | 34 | 60 | 28 | 56 | 34 | 1.6 |
| M36 | 37 | 66 | 30 | 60 | 38 | 1.6 |
| M39 | 40 | 72 | 32 | 64 | 41 | 1.6 |
| M42 | 43 | 78 | 35 | 70 | 44 | 1.6 |
| M45 | 46 | 85 | 38 | 75 | 48 | 1.6 |
| M48 | 50 | 92 | 40 | 80 | 50 | 1.6 |
| M52 | 54 | 98 | 44 | 85 | 53 | 1.6 |

Preset list: sizes of the step.parts catalogue (MIT), see `library/NOTICE.md`.