Shear cracking can be very unpredictable, but there are a few factors that increase a material's propensity for shear cracking.

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• Shearing clearance: the "cut" portion during shearing (or stamping) should be 10% of the thickness. When the shearing clearances are too tight, the cut percentage can reach upwards of 50%, leading to shear cracking. Adjusting shear clearances can be difficult when stamping, as hard tooling can't easily be opened. The stiffness, hardness, and sharpness of the blade are also contributing factors.

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• Strength: commercial steels up to grade 50 very rarely shear crack, and shearing clearances are not very critical. For grades 80 and above, shearing clearances are hyper critical. Grade 100 is not intended for cold shearing, and parts are often laser cut.

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• Thickness: shear cracking is more frequently observed in material 3/16" and thicker.