Precision Machining Tolerances

Review the linear dimensions and reamed hole tolerances applicable to precision machined parts adhering to ISO 2768


Permissible deviations ranges in nominal lengths Aluminum F (fine) Hard Metals F (fine) Plastics F (FINE)
0.019 in. (0.5mm) up to 0.118 in. (3mm) ±0.002 in. (±0.05 mm) ±0.002 in. (±0.05 mm) ±0.002 in. (±0.05 mm)
Over 0.118 in. (3mm) up to 0.236 in. (6mm) ±0.002 in. (±0.05 mm) ±0.002 in. (±0.05 mm) ±0.002 in. (±0.05 mm)
Over 0.236 in. (6mm) up to 1.18 in. (30mm) ±0.004 in. (±0.10 mm) ±0.004 in. (±0.10 mm) ±0.004 in. (±0.10 mm)
Over 1.18 in. (30mm) up to 4.72 in. (120mm) ±0.006 in.(±0.15 mm) ±0.006 in. (±0.15 mm) ±0.006 in. (±0.15 mm)
Over 4.72 in. (120mm) up to 15.74 in. (400mm) ±0.008 in. (±0.20 mm) ±0.008 in. (±0.20 mm) ±0.008 in. (±0.20 mm)
Over 15.74 in. (400mm)  ±0.012 in. (±0.30 mm) ±0.012 in. (±0.30 mm) ±0.012 in. (±0.30 mm)
 
  Aluminum Hard Metals Plastics
Hole Diameter +/- 0.005 in. (0.12mm) 0.005 in. (0.12mm) 0.005 in. (0.12mm)
Hole Depth +/- 0.005 in. (0.12mm) 0.005 in. (0.12mm) 0.010 in. (0.25mm)
Reamed Holes +/- (Thru) 0.0005 in. (0.012mm) 0.0005 in. (0.012mm) 0.002 in. (0.05mm)