Library › Hardware › Pistons Ø29.9 × 30 and Ø39.9 × 40

power piston Ø40 (= the Ø40 liner bore; clearance-seal running fit) × 40, Ø5 rod bore

Exact dimensions. True size, no printing tolerance added. Threads are plain cylinders at the major diameter.

STEP STL free, CC BY 4.0 (credit "Xem Studio")

Dimensions

file	power-piston-40x40
diameter	39.9
length	40
liner bore	40
radial gap	0.05
rod bore	5

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From the full sheet

Pistons Ø29.9 × 30 and Ø39.9 × 40: every size, notes, mating features and sources. What piston fits a 30 or 40 mm cylinder liner?

Other sizes

power piston Ø30 (= the Ø30 liner bore; clearance-seal running fit) × 30, Ø5 rod bore