Metric fine

M52 × 1.5

Tap drill 50.5 mm for a M52 × 1.5 thread — major Ø 52 mm, pitch 1.5 mm (16.93 TPI).

Tap drill
50.5 mm
50.5 mm · ≈77% thread

Profile

Thread form & key diameters

Major Ø 52 mmP 1.5 mm60°Minor Ø 50.16 mm · Pitch Ø 51.026 mmM52 × 1.516.93 TPI · 60° form

Dimensions

DesignationM52 × 1.5
Major (outside) diameter52 mm · 2.0472"
Pitch1.5 mm · 16.93 TPI
Pitch diameter51.026 mm · 2.0089"
Minor diameter (external)50.16 mm · 1.9748"
Minor diameter (internal)50.376 mm · 1.9833"
Recommended tap drill50.5 mm · ≈77% thread
Clearance holeClose 54 · Normal 56 · Loose 62 mm
Hex head (across flats)80 mm

ISO 273 clearance holes (fine / medium / coarse).

Tightening torque estimate

Target preload is 75% of proof load; torque is estimated from T = K · F · d.

Grade / classStress areaPreloadTorque
Class 8.82010.3 mm²874.49 kN9094.7 N·m
Class 10.92010.3 mm²1251.43 kN13014.8 N·m
Class 12.92010.3 mm²1462.51 kN15210.1 N·m
These figures assume a nut factor of K = 0.20 (dry / as-received steel). K captures thread and head friction and can swing torque by 30% or more — a lubricated joint needs noticeably less. Change the lubrication assumption in the bolt-torque calculator.

What tap drill do I need for M52 × 1.5?

For a M52 × 1.5 thread, drill the hole with a 50.5 mm tap drill (50.5 mm — the standard D − P rule) before tapping. That produces roughly 77% thread engagement, the usual target for a strong, tappable hole. The mating bolt has a major diameter of 52 mm and a pitch of 1.5 mm (16.93 TPI).

To pass a M52 × 1.5 bolt through a part rather than thread it, use a clearance hole: Close 54 · Normal 56 · Loose 62 mm.

All values are generated from the standard thread formulas (ISO 68-1 / ASME B1.1) and published standard tables — not hand-entered. See the full reference.

Same diameter

Other M52 threads

Nearby sizes

More metric fine threads