B2B MANUFACTURING RESOURCE • CALCULATORS • DFM GUIDES

Manufacturing Engineering Library & Calculators

Empowering aerospace design engineers and defense procurement teams with technical sheet metal calculation tools, empirical bend deduction formulas, sheet metal gauge-to-weight conversions, and DFM tolerance guidelines.

Launch Bend Calculator ↓ Sheet Metal Gauge Chart ↓

Interactive Engineering Tool

Precision Bend Deduction & K-Factor Calculator

Calculate Bend Allowance ($BA$), Outside Setback ($OSSB$), and Bend Deduction ($BD$) in real time. Use these values in SolidWorks, Inventor, or AutoCAD to calculate exact sheet metal flat pattern blank lengths before laser cutting.

Bend Input Parameters

Select Alloy & Temper

Material Thickness (T) [in] e.g. 0.060″ (16 Ga)

Inside Bend Radius (R) [in] Usually 1T for mild steel/al

Bend Angle (A) [degrees] Default 90.0°

K-Factor (K) [Ratio] Neutral axis ratio (0.3 – 0.5)

Calculated Flat Pattern Results

Bend Allowance (BA) 0.132″ Arc length of neutral axis

Outside Setback (OSSB) 0.120″ Tangent point to apex

Bend Deduction (BD) 0.108″ 2 × OSSB − BA

Applied Engineering Formulas:

• BA = (π/180) × A × (R + K × T)
• OSSB = tan(A/2) × (R + T)
• BD = (2 × OSSB) − BA
• Flat Blank = Flange 1 + Flange 2 − BD

* Note: Values assume TRUMPF precision air bending on our TruBend 5130 press brakes. Dynamic hydraulic crowning guarantees consistency over the full 10-foot bed.

Reference Standards

Sheet Metal Gauge, Thickness & Weight Matrix

Standard sheet metal thickness and weight per square foot across Aluminum, Stainless Steel, and Carbon Steel.

Gauge (Ga)	Decimal Thickness	Metric (mm)	Carbon Steel (lb/ft²)	Stainless 304 (lb/ft²)	Aluminum 6061 (lb/ft²)
10 Ga	0.1345″	3.416 mm	5.625 lb	5.753 lb	1.945 lb
11 Ga	0.1196″	3.038 mm	5.000 lb	5.114 lb	1.730 lb
12 Ga	0.1046″	2.657 mm	4.375 lb	4.474 lb	1.513 lb
14 Ga	0.0747″	1.897 mm	3.125 lb	3.195 lb	1.080 lb
16 Ga	0.0598″	1.519 mm	2.500 lb	2.556 lb	0.865 lb
18 Ga	0.0478″	1.214 mm	2.000 lb	2.045 lb	0.691 lb
20 Ga	0.0359″	0.912 mm	1.500 lb	1.534 lb	0.519 lb
22 Ga	0.0299″	0.759 mm	1.250 lb	1.278 lb	0.432 lb
24 Ga	0.0239″	0.607 mm	1.000 lb	1.022 lb	0.346 lb

16 Ga (0.0598″ / 1.519 mm) 16 GA

Carbon: 2.50 lb/ft²

SS 304: 2.56 lb/ft²

Al 6061: 0.87 lb/ft²

14 Ga (0.0747″ / 1.897 mm) 14 GA

Carbon: 3.13 lb/ft²

SS 304: 3.20 lb/ft²

Al 6061: 1.08 lb/ft²

12 Ga (0.1046″ / 2.657 mm) 12 GA

Carbon: 4.38 lb/ft²

SS 304: 4.47 lb/ft²

Al 6061: 1.51 lb/ft²

Design For Manufacturability

Sheet Metal DFM Engineering Rules

Following these core DFM principles during CAD modeling avoids costly tooling re-designs, eliminates hole elongation, and ensures rapid quotation turnaround.

DFM 1

Minimum Hole-to-Bend Distance

Holes placed too close to a bend line will deform into an ellipse. The minimum distance from the hole edge to the tangent of the bend radius must be at least $2T + R$.

Min Dist ≥ 2 × Thickness + Inside Radius

DFM 2

Minimum Flange Height

A bent flange must be long enough to span across the bottom press brake V-die opening during forming. A reliable minimum flange height rule is $4T + R$.

Min Flange ≥ 4 × Thickness + Inside Radius

DFM 3

Corner Bend Relief Notches

When two bends meet at a corner, metal tearing will occur without proper relief. Relief notches should be at least $1.5T$ in width and extend past the tangent line of both bends.

Relief Width ≥ Material Thickness ($T$)

ENGINEERING KNOWLEDGE BASE

Specialized Engineering Reference Guides & Tools

Deep-dive technical resources developed by Fabtron's Plainville manufacturing staff for aerospace and defense design engineers.

Interactive Tool

Bend Deduction & K-Factor Calculator

Standalone interactive calculator for Bend Allowance, Outside Setback, and Flat Pattern blanks.

Launch Calculator →

Metallurgical Matrix

Sheet Metal Gauge & Weight Matrix

Complete decimal equivalents and lb/ft² density charts for carbon steel, stainless, and aluminum.

View Gauge Matrix →

DFM Design Rules

Hole-to-Edge & Hole-to-Bend Rules

Prevent teardrop ovalization and flange tearing during CNC press brake forming.

Read Design Rules →

AWS Welding Guide

AWS Weld Joint Design & Sizing

Fillet weld leg sizing, groove preparations, and robotic torch accessibility standards.

View Joint Guide →

Finishing Chemistry

Powder Coating Selection Guide

Comparison of TGIC polyesters, epoxies, polyurethanes, and outgassing mitigation.

Read Selection Guide →

CAD Engineer Checklist

25-Point Sheet Metal DFM Checklist

Essential checklist for mechanical engineers before submitting 3D CAD drawings for RFQ.

View DFM Checklist →

Have Questions Regarding Tolerances or CAD Formats?

Our senior manufacturing engineers in Plainville, CT review 3D CAD models (STEP, SLDPRT, DXF) daily for aerospace and defense manufacturability.

Submit CAD for DFM Review → Call: (860) 410-1801