Sheet Metal Flat Pattern Calc

Rolling a 30-degree cone reducer - what flat blank arc radius and angle before you cut? Cones, cylinders, segmented elbows with seam allowance. $4.99 one-time, no login.

Need the flat blank dimensions for a cone, cylinder, or segmented elbow before cutting sheet metal? Enter your finished part geometry and instantly get the developed flat pattern — arc radii, arc angles, gore layouts, and seam allowances. No more hand-drafting on the shop floor.

WHAT IT CALCULATES:

Cones:

• Flat blank inner and outer radius
• Blank arc angle
• Blank arc length
• Developed (flat) blank dimensions

Cylinders:

• Circumference and blank width
• Flat blank length and height
• Material allowance for seams

Elbows:

• Multi-piece elbow segment patterns
• Gore dimensions for each segment
• Throat and heel radius calculations

KEY FEATURES:

• Imperial (in) and Metric (mm) unit support
• Cone, cylinder, and elbow pattern types
• Adjustable wall thickness and seam allowance
• Instant results as you type
• Clean, easy-to-read layout
• Works completely offline
• No account or login required

BUILT FOR THE SHOP FLOOR:

Whether you are a sheet metal worker, HVAC fabricator, or mechanical estimator, this app gives you accurate blank dimensions for cutting and rolling. Enter your finished part geometry and get your flat layout in seconds.

Calculations follow standard sheet metal development methods for right circular cones, cylinders, and segmented elbows.