What a ply weighs and measures
A prepreg name reads as a datasheet (M56/35%/UD134/AS7-12K); cured thickness adds per ply (16 × 0.134 = 2.144 mm, exactly the spar web in AddPly), and net mass is area × plies × areal mass (0.302 m² × 16 × 206 g/m² ≈ 1 kg).
Predict · at 0:56 in the video
The wing spar's web in AddPly is declared at 2.144 millimetres. How many of these plies is that?
Sixteen. 16 times 0.134 is 2.144. And that's what AddPly's design overview shows for the web: sixteen plies, 2.14 millimetres.
This course is our own. These books go deeper.
- Basic Mechanics of Laminated Composite Plates, A. T. Nettles, NASA Reference Publication 1351, 1994
- Mechanics of Composite Materials, R. M. Jones, Taylor & Francis, 2nd ed., 1999
- Engineering Mechanics of Composite Materials, I. M. Daniel & O. Ishai, Oxford University Press, 2nd ed., 2006
- Design and Analysis of Composite Structures, C. Kassapoglou, Wiley, 2nd ed., 2013
- Composite Materials Handbook (CMH-17), Volume 3, Rev. G, CMH-17, SAE International, 2012
The course designs in AddPly, our browser app for laminate design: regions, ply stacks with live stacking-rule checks, thickness, mass and the ply book. It does not do strength, failure or draping; where a lesson covers those, the simulation is our own.
Simulations in this lesson are our own. Ply data come from the datasheet or textbook named on screen; where a number rests on an assumption, the video says so.
