b'Bender LocationDesign FormulasBender Locationand Design Formulas:Bender Location . K Dim. 1. Bender location . CAD compatible K DimensionThe K Dimension is the distance The K Dimension changes as an over-between the centerline of the anvil radius bend is added to or subtracted from theand thecenterline of a fully closed bending lobe. Though the centerline of therocker. Its purpose is to aid the designer rocker is constant, it will move closer to orin dimensioning the key slots needed to further from the anvil radius.locate the READY Bender easily. These formulas are only valid for squareWhen the toolmaker actually sets the 90 bend angles. For overbends up toREADY Bender, he is in fact setting to 135 or underbends down to 60, pleasethe K Dimension. Correct setting of the consult READY. Due to the trigonometric3 OVERBEND bender will provide for longer tool life variations, the formulas are completelyand better parts. changed and can not be generalized.The formula for the K dimension of a87 standard rocker is:Formula for A = 87,rockerK= PT+PRTan (A/2)87Angle A:87 Standard2. Tonnage Formula for READY BendersREADY Bendersrequire 50-80% less F = force required tonnage than wipe bending tools. The S= nominal ultimate tensile strengthT clamping lobe provides part holddown W=width of bend from rst contact, the bending lobe has T= stock thicknessT greater bending leverage. The ability to L= span (as a beam) L=B+R+Toverbend up to 135 eliminates the need B= designer dimension of 1 dia. rockerfor coining and bottoming. R= anvil radiusExample:(Clamp position shown solid,F= 2.25 x SWT2 ; L= B 1 + T + R = 0.343 + 0.060 + 0.060 = 0.463overbend position dotted) L (1 DIAMETER ROCKER)Benders require 50-80% less tonnage F = 2.25 x 50,000 x 1 x 0.060 2= 875 lb. = 0.44 tonthan wipe tools. 0.4633. General Bend Allowance FormulaREADY Bendersoverbend to allow for Caution. As we all know, bend allowance mayspringback instead of coining the part change with different materials and even withinmaterial to set the bend. As a result, different coils of the same material. The onlybenders leave more material within the way to be sure of the bend allowance is to testbend radius so the bend allowance is bend the material and measure the BA. (Seegreater than wipe bending.Test Bending Service, page 19).Bend Allowance The general formula is:12 Bend Allowance (BA) =.01745 x PA x [PR + (PT x .43)]'