Mechanical & Civil Engineering
Sheet Metal Bend Deduction & K-Factor Calculator
Calculate bend allowance and bend deduction for sheet metal forming using the K-factor method.
Your inputs
Change any value to update the result instantly.
Bend allowance
6.095 mm
Bend deduction
3.905 mm
Outside setback
5 mm
K-factor
0.44
What this calculator does
Sheet Metal Bend Deduction & K-Factor Calculator: Applies the standard shop-floor or joint-design relationship so the force, speed, allowance or strength can be worked out from the process inputs.
What your result means
The headline figure is the process setting or joint strength implied by your inputs. Treat it as a starting point to validate against the tool maker's data and a trial part.
Formula and working
BA = (π/180) × angle × (radius + K×thickness); BD = 2×OSSB - BA
- 1
Collect the inputs
Material thickness = 2 mm; Inside bend radius = 3 mm; Bend angle = 90 deg; K-factor = 0.44
- 2
Apply the formula
BA = (π/180) × angle × (radius + K×thickness); BD = 2×OSSB - BA
- 3
Result
Bend allowance = 6.095 mm
Frequently asked questions
Symbols and assumptions
- thickness
- Material thickness (mm)
- bendRadius
- Inside bend radius (mm)
- bendAngle
- Bend angle (deg)
- kFactor
- K-factor
- • Nominal tooling, material and process conditions are assumed; machine, tool-wear and lubrication effects vary in practice.
- • Recommended cutting data always sits inside the tool maker's published envelope, which takes priority.
Sources and review
Reviewed 2026-09-22 · Next review 2027-09-22
- • This is an educational estimate for learning and checking, not a design deliverable.
- • Real design must follow the governing code or standard for your jurisdiction and be reviewed and signed off by a qualified engineer.
- • Safety factors, load combinations and material certification are the responsibility of the designer, not of this page.
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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