Isotropic metal
For many early laminate comparisons, formed sheet and machined metal parts are approximated as having the same properties in every in-plane direction. The main design levers are thickness and shape.
AddPly · your composite part starts here
Turn your mold into a clear composite layup.
Bring a STEP model or start with an example. Choose where the material goes, build your ply stack, and see its thickness and material coverage. Take away an editable design and a printable schedule showing what to lay down, where, and in what order.
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60 → 48 plies15.240 → 12.192 mm0° 43% · ±45° 47% · 90° 10%4 rib baysNACA 2412 · public-domain section
AddPly defines the laminate. AddPath is the separate path-planning product. The handoff contains design intent, with no courses, paths or machine program.
- Aerospace
- Defence
- Automotive
- Pressure vessels
- Advanced industrial
Target industries. These are not delivered or qualified parts and imply no customer or certification.
Published reference studies
Four published laminates, inspectable in AddPly
Three NASA cylindrical-shell specimens and one NASA sandwich-cylinder facesheet, transcribed from their published sources and shipped as reference studies in the composites bench. Every number says whether the source published it, AddPly chose it, or it is derived from the two.
NASA shell C1 sector (axially stiff)
Source NTRS 20140011912
[-45/+45/0_2]s
- -45°
- 0°
- 45°
- Shell nominal radius
- 8.0 in / 203.2 mmPUBLISHED
- Shell nominal length (axial)
- 16.0 in / 406.4 mmPUBLISHED
- Sector angle
- 90deg (1/4 of the shell)CHOSEN
- Sector arc length (tool u extent)
- 319.186 mmDERIVED
- Nominal wall thickness
- 0.04 in / 1.016 mmPUBLISHED
A SECTOR, not the closed cylinder. The sector angle is ours; the radius and length are published.
Source locator and every limitation
Specimen laminates, material and geometry: printed p.3. Wall thickness, R/t, potting and test-section length: printed p.4.
- A SECTOR, not the closed cylinder. The sector angle is ours; the radius and length are published.
- A subscale laboratory buckling coupon, not a vehicle, a fairing or anyone's part.
- No strength, buckling, producibility, drape or qualification claim is made or implied.
- Authored at the NOMINAL ply thickness. The source separately measured C3 at a 0.0381 in average wall, 4.75 % thinner than nominal.
- Areal mass is undeclared because the source publishes none.
NASA shell C2 sector (circumferentially stiff)
Source NTRS 20140011912
[-45/+45/90_2]s
- -45°
- 45°
- 90°
- Shell nominal radius
- 8.0 in / 203.2 mmPUBLISHED
- Shell nominal length (axial)
- 16.0 in / 406.4 mmPUBLISHED
- Sector angle
- 90deg (1/4 of the shell)CHOSEN
- Sector arc length (tool u extent)
- 319.186 mmDERIVED
- Nominal wall thickness
- 0.04 in / 1.016 mmPUBLISHED
A SECTOR, not the closed cylinder. The sector angle is ours; the radius and length are published.
Source locator and every limitation
Specimen laminates, material and geometry: printed p.3. Wall thickness, R/t, potting and test-section length: printed p.4.
- A SECTOR, not the closed cylinder. The sector angle is ours; the radius and length are published.
- A subscale laboratory buckling coupon, not a vehicle, a fairing or anyone's part.
- No strength, buckling, producibility, drape or qualification claim is made or implied.
- Authored at the NOMINAL ply thickness. The source separately measured C3 at a 0.0381 in average wall, 4.75 % thinner than nominal.
- Areal mass is undeclared because the source publishes none.
NASA shell C3 sector (quasi-isotropic)
Source NTRS 20140011912
[-45/+45/0/90]s
- -45°
- 0°
- 45°
- 90°
- Shell nominal radius
- 8.0 in / 203.2 mmPUBLISHED
- Shell nominal length (axial)
- 16.0 in / 406.4 mmPUBLISHED
- Sector angle
- 90deg (1/4 of the shell)CHOSEN
- Sector arc length (tool u extent)
- 319.186 mmDERIVED
- Nominal wall thickness
- 0.04 in / 1.016 mmPUBLISHED
A SECTOR, not the closed cylinder. The sector angle is ours; the radius and length are published.
Source locator and every limitation
Specimen laminates, material and geometry: printed p.3. Wall thickness, R/t, potting and test-section length: printed p.4.
- A SECTOR, not the closed cylinder. The sector angle is ours; the radius and length are published.
- A subscale laboratory buckling coupon, not a vehicle, a fairing or anyone's part.
- No strength, buckling, producibility, drape or qualification claim is made or implied.
- Authored at the NOMINAL ply thickness. The source separately measured C3 at a 0.0381 in average wall, 4.75 % thinner than nominal.
- Areal mass is undeclared because the source publishes none.
CTA8.3 IML facesheet end region
Source NASA/TM-20205008667
Table 3, p.14: [30/-45/-30/45/90/45/-30/-45/30] at the end, [30/-30/90/-30/30] in the acreage
- -45°
- -30°
- 30°
- 45°
- 90°
- Cylinder radius
- 48.0 in / 1219.2 mm (8-ft diameter)PUBLISHED
- Cylinder length
- 100 in / 2540 mmPUBLISHED
- Modelled axial extent from one cylinder end
- 24 in / 609.6 mmCHOSEN
- Sector angle
- 45deg (1/8 of the shell)CHOSEN
- Sector arc length (tool u extent)
- 957.557 mmDERIVED
The project opens, but curved laminate buildup is currently refused at the internal ply drops: full-area plies overhang shorter substrates and need an unsupported curved cover transition. The gallery depicts the base surface and authored schedule. Use the developed companion for station sampling.
Source locator and every limitation
Table 1 "Closed-form designs", printed p.11-12. Table 3 "Core transition and layups in acreage and pad-up regions", printed p.14 (PDF p.23). Cylinder length, section 2.1, printed p.5 (PDF p.14). Material, AFP manufacture, core and pad-up description: printed p.13.
- Table 3 is visually verified against the source page; the six sequences are used exactly as printed.
- ONE FACESHEET, not a sandwich. The 0.20 in honeycomb core, its density transition, the core splices and the outer facesheet are not modelled.
- A SECTOR and an END REGION, not the closed cylinder. The sector angle is ours.
- The project opens, but curved laminate buildup is currently refused at the internal ply drops: full-area plies overhang shorter substrates and need an unsupported curved cover transition. The gallery depicts the base surface and authored schedule. Use the developed companion for station sampling.
- A 24 in CROP of the published 100 in cylinder. The crop is ours; the station boundaries in it are published.
- A subscale test article designed to populate a design space, not a launch vehicle.
- No strength, buckling, producibility, drape or qualification claim is made or implied.
- Fibre areal weight 145 g/m2 is published but is NOT a prepreg areal mass; areal mass is undeclared.
Reproducing a published stacking sequence means the transcription is right and the laminate is internally consistent. It is NOT a strength, buckling, producibility, drape, airworthiness or qualification claim, and none of these documents is a flight article. Each number carries whether the source PUBLISHED it, we CHOSE it, or it is DERIVED from the two.
Open published library
The link opens AddPly’s published-component library, not a particular study. Select any card to open it in the composites bench. These curved studies can be inspected and documented there; the CAD laminate workspace intentionally refuses to convert them into a planar editable tool instead of flattening them. Drawings here are rendered by AddPly from each study’s declared tool and stack; they are not images of the source documents.
Material transition
From isotropic metals to orthotropic laminates
Metal parts are often approximated as isotropic during early comparisons. A composite laminate is built from plies whose stiffness depends on the direction the fibres run — so the design question moves from how thick, to which way and in what order.
Orthotropic composite
A stacked laminate is stiff and strong along the fibre direction and relies on the matrix across it. Ply angles and stacking order place that direction where the design needs it.
Declared design intent
AddPly records each ply’s angle against an explicit projection plane or a named rosette. It is intent you can read back — not a drape, a course or a solved fibre path.
Workflow
From STEP faces to a handoff, in one browser session
Keep your tooling geometry and laminate definition together as the design develops.
- 01
Select faces
Import STEP geometry. Select one or many trimmed faces in the viewport or face list, then name your tooling group.
- 02
Draw across faces
Draw a closed polygon on XY, XZ or YZ. The CAD kernel cuts its projection against the faces in your tooling group.
- 03
Define the stack
Assign material, thickness and declared orientation to each ply. Edit, duplicate and reorder the stack, with an explicit rosette reference.
- 04
Save and reopen
Keep a named project in this browser. Export a portable project backup to carry the exact geometry and design to another computer.
- 05
Export a handoff
Download open HDF5 or an AddPath handoff package with selected STEP support faces and laminate design intent.
Capabilities
Built around the laminate
Multi-face tooling
Treat adjacent CAD faces as one tooling group. Select the surfaces that make up the layup tool and keep the surrounding geometry for context.
Across-face regions
One projected boundary can span several faces. Exact clipped areas come from the CAD kernel, with the source geometry’s existing trims preserved.
An editable ply stack
Keep material, thickness, region and orientation together. Undo changes and read the declared thickness for each region.
Materials and rosettes
Record your material references and the reference frame for ply angles. Orientation remains declared design intent; AddPly does not solve drape.
Projects with CAD context
Reopen saved projects with their tooling, boundaries and plies. Browser storage reports when a save succeeds and offers recovery when available.
Open formats
Read the documented HDF5 package in your own tools, or reopen supported AddPly HDF5 files for editing. Export a revision-stamped printable plybook.
Interoperability · open format
Your data leaves in a format you can read
HDF5 is an open format available to anyone. AddPly’s documented package carries selected STEP support surfaces, regions, ordered plies, materials and rosettes.
- Open supported AddPly HDF5 packages back into an editable CAD laminate.
- Export a versioned .addply-handoff package for an AddPath importer.
- Keep the full project as a portable .cad-laminate.json backup.
The AddPath receiving adapter is still to be built and tested. Exporting a package does not send it to AddPath or establish consumer compatibility.
WORKSPACEAddPlyLaminate design
.ADDPLY.H5Open HDF5Read and reopen
.ADDPLY-HANDOFFAddPath packageFor a receiving adapter
Where your work lives
A browser workspace, with clear boundaries
Geometry stays with you
The CAD kernel runs in your browser. Opening a STEP file does not upload your geometry. Your Addcomposites account identifies you; projects stay in this browser. Optional server processing requires your separate consent.
Local means this browser
Saved projects belong to this browser and site address. They do not sync across devices. Export a backup before clearing browser data.
Declared engineering data
Materials are your own records, not certified allowables. Ply angles are declared references, not drape results or solved fibre paths.
Desktop CAD workflow
Use a desktop browser and mouse. Boundaries are polygons projected along X, Y or Z; freeform surface drawing and edge offsets are not supported.
Learn about your data and browser storage, or follow the quick start guide.
Bring your surfaces.
Build your laminate.
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