Practical tools for measured work
Truncated-Pyramid Flat-Pattern Developer
Develop the four true-size trapezoid panels for a centered rectangular truncated pyramid.
Calculate the layout, check the diagram, then print the result for the shop or jobsite.
How it works
A centered rectangular frustum separates into two matching front/back trapezoids and two matching side trapezoids. Each true panel height combines vertical height with the corresponding horizontal inset.
Current-input example
The result above uses these exact values. This snapshot is included when the page is printed so the output can be checked against the original measurements.
- Bottom width
- 600 mm
- Bottom depth
- 400 mm
- Top width
- 300 mm
- Top depth
- 200 mm
- Vertical height
- 500 mm
- Seam allowance
- 0 mm
Primary result: Front/back slant: 509.90 mm.
Before using the result
- Measure from the datum or reference edge described by this tool, and do not mix inside, outside and centerline dimensions.
- Keep inputs in the displayed units and preserve more precision than the final cutting or purchasing tolerance requires.
- When the result is close to a limit, verify it with a test piece, field measurement, manufacturer drawing or qualified project professional.
Limitations
This creates separate theoretical face panels for a centered, square-corner transition. Add bend, weld, lap and material-thickness allowances according to your fabrication process.
Frequently asked questions
What should I verify before using this result?
Recheck the physical measurements, confirm that every input uses the displayed unit, and compare the result with the applicable drawing, product specification, code requirement or test piece.
Why might the finished result differ?
Real work can include thickness, kerf, seams, tolerances, hardware allowances, installation clearances or site conditions that are outside the calculation. The limitations section identifies the main exclusions for this tool.
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