What does the drawing to 3D assembly converter actually do?

It reads a 2D assembly drawing in PDF form — the section views, the item balloons with their leader lines, the parts list, the assembly notes and the torque table — and rebuilds the assembly as an interactive 3D model in the browser. Each ballooned part becomes its own named mesh, placed where the drawing shows it, so you can explode the assembly along its axes, isolate component groups and click any part to read its part number, quantity, torque and the notes that mention it.

Do I need a STEP, STL or native CAD file?

No. The whole point is that you only have the drawing. The 3D is reconstructed from the vector line-work of the section views: the outline strokes bound each part’s cross-section, the dash-dot centreline gives the axis of revolution, and the balloon tells which part is which. If you do have a STEP or STL file, Aginera’s STEP to 3D + BOM tool at aginera.ai/tools/step-to-bom reads the real geometry instead and is the better choice.

How accurate is the 3D model?

Exactly as accurate as the section view, and no more. Parts drawn in section are revolved about the drawn centreline, so turned parts — shafts, pistons, bushes, seals, nuts, caps, springs’ envelopes — come out true to the drawing. Non-axisymmetric bodies such as a cast valve block are approximated from the two orthogonal sections. Dimensions are the drawing’s units and most assembly drawings are marked not to scale, so treat the model as a faithful visual of the sheet rather than as manufacturing geometry.

Is any of the geometry generated by AI?

No. The reconstruction is deterministic: flood-filling the enclosed section under each leader tip, revolving that region about the centreline, and reading the tables from the PDF text layer. Nothing is hallucinated, which also means the tool is honest about its limits — an item that only appears in an exploded isometric or an exterior view is listed in the parts list but shown as not modelled.

What kinds of drawings work best?

Vector PDFs exported from CAD (SolidWorks, Inventor, Creo, NX, AutoCAD, Fusion) of assemblies whose parts are largely bodies of revolution: hydraulic and pneumatic cylinders, valves, pumps, gearbox shaft assemblies, spindles, couplings, actuators, jacks, filters and fittings. Block-shaped bodies such as a valve manifold are handled when the sheet carries two orthogonal sections; vertical assemblies are fine. The sheet needs section views with balloons pointing into hatched part regions, a drawn centreline, and a parts list with an item column. Scanned or photographed drawings are raster images and are not supported.

Can I get the parts list out of the drawing as a spreadsheet?

Yes. The parts list is read from the PDF text layer, matched to the balloons, and can be exported to Excel with item number, description, part number, quantity, a make/buy sourcing guess from the part-number pattern, the tightening torque where the sheet gives one, and every assembly note that references the item.

Is it free, and can I try it with my own drawing?

The tool and its six original sample drawings — a solenoid directional valve with a block body and two sections, an end-suction centrifugal pump, a hydraulic cylinder, a gearbox input shaft, a vertical screw jack and a pressure relief valve, all drawn by Aginera and free to download — are free with no signup. Own-drawing upload runs as a prototype service: send a sheet to hello@aginera.ai and you get the reconstructed assembly back. The same section-reading engine powers Aginera’s construction takeoff platform for MEP drawings.

Maintenance and reliability teams who hold legacy paper-style drawings but no CAD; sales and training teams who want an interactive exploded view of a product without commissioning a 3D artist; procurement teams who need the parts list out of a supplier’s drawing; and engineers checking a vendor’s assembly drawing against what arrived in the crate.

Plan to 3D Plan to Video Room Designer Plan to Takeoff Drawing to 3D

2D Drawing → 3D Assembly + Parts List

Turn a PDF assembly drawing into an explodable 3D model

Name: Aginera DesignOps
Author: Aginera

No STEP file? Aginera reads the section views of a 2D assembly drawing, rebuilds every ballooned part in 3D, and links each one back to the parts list, torque table and assembly notes on the sheet. Deterministic geometry — no guessing.

Upload a PDF drawing

Read parts list & notes

Reconstruct 3D from sections

Explode, inspect, export

Open the sample assembly Have a STEP file instead? STEP → 3D + BOM

Or try a sample: Download this sample PDFOwn drawings: prototype — send us a sheet

Drag to orbit · click, then scroll to zoom · click a part or a component group · slide to explode. Dimensions are drawing units; the sheet is marked not to scale.

Built from the PDF alone: no CAD file, no AI-generated geometry.

What is drawing-to-3D assembly reconstruction?

Drawing-to-3D assembly reconstruction turns a conventional 2D assembly drawing — section views, item balloons, a parts list — into a 3D model of the assembly without any CAD file. Aginera does it deterministically: each balloon is traced to the enclosed, hatched region it points at, that cross-section is revolved about the drawing's centreline, and the resulting parts are placed together so the assembly can be exploded, isolated and inspected part by part, with every part still linked to its row in the parts list, its torque and the notes that mention it.

It is the 2D-drawing counterpart of Aginera's STEP to 3D + BOM tool: that one starts from real 3D geometry and derives the fabrication BOM; this one starts from the sheet alone and derives both the 3D and the BOM. Same engine family as the section-reading pipeline behind Aginera's construction takeoff.

How it works

1 · Start from a 2D assembly drawing
A vector PDF of an assembly drawing with section views, item balloons and a parts list — the kind every mechanical assembly ships with. No STEP, no native CAD file needed. Pick one of the six original samples or download them to see the format.
2 · Balloons are traced into the sections
Each item balloon is followed down its leader. The thick outline strokes form barriers and a flood fill under the leader tip yields that part’s exact cross-section. Nothing is guessed: if a part is not ballooned in a section, it is listed but not modelled.
3 · Sections become solids
Every cross-section is revolved about the drawn dash-dot centreline (or one inferred from part symmetry; radial parts about their own axis). Bodies with two orthogonal sections are extruded from both. The result is one named mesh per part, positioned in a single frame.
4 · Explode, inspect, export
Slide to explode along each part’s own axis, isolate a component group, click any part to see its part number, torque and the assembly notes that mention it, and jump to where it sits on the sheet. Export the parts list with sourcing and torque to Excel.

Six original sample drawings, free to download

Every sample was drawn by Aginera for this tool, so you can download the PDFs, study how a sheet needs to be laid out for a clean reconstruction, and reuse them freely for evaluation:

DCV-16-4W3 solenoid directional valve — 16 items, block body from two orthogonal sections, mounting feet, ports, pilot relief in a parallel bore.
PC-050-160 end-suction centrifugal pump — 14 items, volute casing, closed impeller, mechanical seal, bearing frame, coupling half.
HC-063-250 double-acting hydraulic cylinder — 13 items, clevis and rod-end-eye mounting, port plugs.
GB-210-IS gearbox input shaft — 13 items, two ball bearings, spur gear on a key, lip seal, circlip.
SJ-005-300 5 t screw jack — 11 items, vertical section, conical base, bronze nut, swivel cup, radial tommy bar.
RV-020-350 pressure relief valve — 12 items, lapped seat and poppet, spring, adjusting screw, lead-seal cap.

Turn a PDF assembly drawing into an explodable 3D model

What is drawing-to-3D assembly reconstruction?

How it works

Six original sample drawings, free to download

Questions

Other free tools

Need quantities, not just a model?