HSS-E Oversize Spiral Point Tap Whitworth OS-POT-W
The OS-POT-W is an oversize tap made of cobalt high-speed steel (HSS-E) — oversized thread to allow for plating thickness or to compensate for material shrinkage after tapping. It comes in 40 sizes (thread dia 1/8~3/4).
Specifications (40 items)
| Part No. | Standard | Dia. | Oversize |
|---|---|---|---|
| ANBWCOS-POT-W_1/8+3 | Whitworth W | 1/8 | 0.03 |
| ANBWCOS-POT-W_1/8+5 | Whitworth W | 1/8 | 0.05 |
| ANBWCOS-POT-W_1/8+7 | Whitworth W | 1/8 | 0.07 |
| ANBWCOS-POT-W_1/8+10 | Whitworth W | 1/8 | 0.1 |
| ANBWCOS-POT-W_5/32+3 | Whitworth W | 5/32 | 0.03 |
| ANBWCOS-POT-W_5/32+5 | Whitworth W | 5/32 | 0.05 |
| ANBWCOS-POT-W_5/32+7 | Whitworth W | 5/32 | 0.07 |
| ANBWCOS-POT-W_5/32+10 | Whitworth W | 5/32 | 0.1 |
| ANBWCOS-POT-W_3/16+3 | Whitworth W | 3/16 | 0.03 |
| ANBWCOS-POT-W_3/16+5 | Whitworth W | 3/16 | 0.05 |
| ANBWCOS-POT-W_3/16+7 | Whitworth W | 3/16 | 0.07 |
| ANBWCOS-POT-W_3/16+10 | Whitworth W | 3/16 | 0.1 |
| ANBWCOS-POT-W_1/4+3 | Whitworth W | 1/4 | 0.03 |
| ANBWCOS-POT-W_1/4+5 | Whitworth W | 1/4 | 0.05 |
| ANBWCOS-POT-W_1/4+7 | Whitworth W | 1/4 | 0.07 |
| ANBWCOS-POT-W_1/4+10 | Whitworth W | 1/4 | 0.1 |
| ANBWCOS-POT-W_5/16+3 | Whitworth W | 5/16 | 0.03 |
| ANBWCOS-POT-W_5/16+5 | Whitworth W | 5/16 | 0.05 |
| ANBWCOS-POT-W_5/16+7 | Whitworth W | 5/16 | 0.07 |
| ANBWCOS-POT-W_5/16+10 | Whitworth W | 5/16 | 0.1 |
| ANBWCOS-POT-W_3/8+3 | Whitworth W | 3/8 | 0.03 |
| ANBWCOS-POT-W_3/8+5 | Whitworth W | 3/8 | 0.05 |
| ANBWCOS-POT-W_3/8+7 | Whitworth W | 3/8 | 0.07 |
| ANBWCOS-POT-W_3/8+10 | Whitworth W | 3/8 | 0.1 |
| ANBWCOS-POT-W_7/16+3 | Whitworth W | 7/16 | 0.03 |
| ANBWCOS-POT-W_7/16+5 | Whitworth W | 7/16 | 0.05 |
| ANBWCOS-POT-W_7/16+7 | Whitworth W | 7/16 | 0.07 |
| ANBWCOS-POT-W_7/16+10 | Whitworth W | 7/16 | 0.1 |
| ANBWCOS-POT-W_1/2+3 | Whitworth W | 1/2 | 0.03 |
| ANBWCOS-POT-W_1/2+5 | Whitworth W | 1/2 | 0.05 |
| ANBWCOS-POT-W_1/2+7 | Whitworth W | 1/2 | 0.07 |
| ANBWCOS-POT-W_1/2+10 | Whitworth W | 1/2 | 0.1 |
| ANBWCOS-POT-W_5/8+3 | Whitworth W | 5/8 | 0.03 |
| ANBWCOS-POT-W_5/8+5 | Whitworth W | 5/8 | 0.05 |
| ANBWCOS-POT-W_5/8+7 | Whitworth W | 5/8 | 0.07 |
| ANBWCOS-POT-W_5/8+10 | Whitworth W | 5/8 | 0.1 |
| ANBWCOS-POT-W_3/4+3 | Whitworth W | 3/4 | 0.03 |
| ANBWCOS-POT-W_3/4+5 | Whitworth W | 3/4 | 0.05 |
| ANBWCOS-POT-W_3/4+7 | Whitworth W | 3/4 | 0.07 |
| ANBWCOS-POT-W_3/4+10 | Whitworth W | 3/4 | 0.1 |
Specification Range
| Diameter | 1/8~3/4 |
|---|
Product Description
The OS-POT-W is an oversize tap made of cobalt high-speed steel (HSS-E) — oversized thread to allow for plating thickness or to compensate for material shrinkage after tapping. It comes in 40 sizes (thread dia 1/8~3/4). Supplied uncoated (bright finish). It handles carbon and alloy steel, stainless steel, cast iron, non-ferrous metals such as aluminium and copper, with workpiece hardness up to HRC40. Typical applications: Whitworth through-hole tapping before plating or zinc coating; the thread is cut slightly oversize to allow for the coating thickness, so the screw still fits after finishing. This is the spiral point version, pushing chips ahead. In the same H.T.D family: the oversize spiral flute OS-SFT-W (for blind holes, also 40 sizes), the metric OS-POT-M and the American OS-POT; OS-POT-W covers thread dia 1/8~3/4, every size in four oversize grades: 0.03, 0.05, 0.07 and 0.1mm. How do I choose the oversize? By coating thickness: the thicker the coating, the larger the oversize; every size in this series comes in four grades, 0.03~0.1mm. Can it tap blind holes? For blind holes use the oversize spiral flute OS-SFT-W.
Workpiece Materials & Hardness
- Steel (P)
- Stainless steel (M)
- Cast iron (K)
- Non-ferrous metals (N)
Max. workpiece hardness HRC40
Related Resources
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