The diameter tolerance of a dowel pin determines how it fits in the hole. SFP regularly stocks three types:
| Type | Diameter tolerance (example) | Fit | Use |
|---|---|---|---|
| Minus tolerance (general) | 0 / −0.02 (SFP standard) | Slip fit (transition, on the loose side) | General jig positioning, removable |
| h7 | Per ISO grade (0/−0.012 for φ3-6) | Slip fit (more precise) | Positioning with higher accuracy requirements |
| Plus tolerance (press fit) | +0.005 / 0 (SFP plus-tolerance pins) | Tight / press fit | Pressed into H7 holes for fixing, molds |
Length tolerances are commonly ±0.1 to ±0.2 or −0.2/−0.4 (depending on the item); SFP also has a "special tolerance dowel pin" category for specified tolerances.
To calculate the actual upper and lower deviations of h7 / m6 at each size, or if your drawing only gives a range (e.g. 3(0/-0.014)) and you want to know which code it matches and which stock tolerances meet it, use the tolerance calculator; h7, m6 and H7 each have a full tolerance table.
Hole is H7 and the pin must be "driven in and stay put" → choose plus tolerance; pin must "insert and remove easily" for repeated positioning → choose minus tolerance or h7. If unsure, put the hole size and application in your inquiry and we will choose for you.
Click a size to open its product page (price and stock status); lists update automatically with our stock.
📂 Dowel pin categories (incl. special tolerances)📐 ISO 2338 standard guide