Brakewright Metal Calculator

What it does

Brakewright is a calculator for press brake operators, fabricators, duct and enclosure shops, programmers and students. It works like a hardware calculator: a steel-blue chassis, real keys and a clear LCD, with each answer labelled so you know what you are reading.

Worked examples

• Bend allowance. 16 ga mild steel, 1/16 in radius, 90° -> bend allowance 0.1395 in.
• Flat blank. 16 ga, 1/16 in radius, 1 x 2 x 1 in U channel -> flat blank 3.7898 in.
• Tonnage. 1/4 in plate on a 2 in die, 120 in long -> 179.69 tons total.
• V die. 16 ga on a 0.5 in die -> recommended 8T die 0.4784 in.
• K factor. 16 ga test bend, 1.05 + 1.05 in flanges from a 2 in blank -> K 0.4942.
• Metric tonnage. 3 mm on a 24 mm die -> 25.27 tonnes per metre.

How it's calculated

Every trade key and the formula behind it, as shown in the app's key guide. A second legend is the shifted function.

Thk GaMaterial thickness / Sheet gauge

Stores the typed material thickness T, or recalls it. Shifted turns a typed gauge number into its thickness for the current material; with nothing typed it steps to the next thinner gauge.

Rad AirRInside bend radius / Air bend radius

Stores the typed inside bend radius R, or recalls it. Shifted stores the typical air-bend radius, a fraction of the V-die opening (about 0.16 × V for mild steel), for the typed or stored die, or 8 × T.

Ang InclBend angle / Included angle

Stores the bend angle: how far the sheet is bent, 90 for a right angle (90 until set). Press again for the included angle between the flanges, 180 minus the bend angle. Shifted stores a typed included angle as its bend angle.

BA BDBend allowance / Bend deduction

Bend allowance BA = π ÷ 180 × A × (R + K × T); press again for the outside setback tan(A ÷ 2) × (R + T), the bend deduction 2 × OSSB − BA and K. Shifted starts at the bend deduction. A typed allowance or deduction solves and stores K.

Flng NewFlange / New part

Adds a typed outside flange length and shows the flat blank: the flange sum less one bend deduction per bend at the current angle, radius and K. Change the angle between flanges if bends differ. Shifted starts a new part.

K KTestK-factor / K-factor from test bend

Stores the typed K-factor, or shows it; 0.44 is a typical value when none is stored. Shifted: bend a test blank, enter its measured outside flanges with Flng, type the blank length and press to solve K.

Vdie xTV-die opening / Die opening as a multiple of thickness

Stores the typed V-die opening; with nothing typed steps through it, the recommended 8 × T, the air-bend radius and the minimum flange. Shifted stores a die of the typed multiple of T, or 8 × T.

Ton LenPress brake tonnage / Bend length

Typical air-bend force 575 × T² ÷ V tons per foot (T, V in inches; about 67.4 × T² ÷ V tonnes per metre in mm) times the material factor, and the total for the bend length. A typed length is stored as the bend length. Shifted stores it too.

Mat DataMaterial / Material factors

Steps through mild, galvanized, stainless and aluminium sheet; the material picks the gauge series, the tonnage factor and the air-bend radius. Shifted shows those typical factors.

Hem MinFlHem / Minimum flange

Adds a typed closed hem (outside length) to the flat blank, deducting 2T − πT ÷ 2 ≈ 0.43 × T; nothing typed shows that deduction and an open hem at radius R. Shifted shows the minimum flange, about 0.7 × V.

Die, radius and force figures are rules of thumb. Confirm tonnage against the press brake's rated capacity and the die maker's chart before bending, and verify every result with a test bend. The developer accepts no liability for loss or damage arising from use.