Tutorials PartCraft help Getting started
Files: open, save and export
The part and assembly files PartCraft opens and saves, every export format and what it keeps, where files go, and what changes offline or between browsers.
Written for PartCraft 0.3. The same help is inside the app: press F1.
PartCraft works on files on your computer. It never uploads a part, and there is no account or cloud storage involved. Cloud saving is not available yet.
What PartCraft opens
| File | Extension | How |
|---|---|---|
| A PartCraft part | .partcraft.json | Open, ⌘OCtrl+O, or drop it on the 3D view |
| A PartCraft assembly | .partcraft-asm.json | The same: PartCraft sees which kind it is |
| A STEP solid | .step, .stp | The same. It becomes an imported solid, as a new part or added to the current one. Needs the exact kernel |
STL, DXF, IGES and other programs' own part files cannot be opened (see What is not built yet). How STEP import works: Open a STEP file and build on it.
Rules when opening:
- A part or assembly file name must end in
.json, and the file must be under 50 MB. A STEP file must be under 60 MB and start withISO-10303-21. - Files are checked before anything is shown. A damaged or edited file is refused with a plain reason, for example "This is not a PartCraft file."
- A file saved by a newer PartCraft is refused: "This file was saved by a newer PartCraft (file version 3); this one reads version 2." Older files open.
- If the part on screen has unsaved changes, PartCraft asks first: Cancel, Discard changes or Save first.
Saving
Save or ⌘SCtrl+S saves what is on screen:
- On a part:
<part name>.partcraft.json, the complete history (sketches, relations, dimensions, features, the rollback position), the drawing sheet's section, detail and GD&T notes, and the full text of any imported STEP solid. The solid itself is not stored; PartCraft rebuilds it from the history when the file opens. - In an assembly:
<assembly name>.partcraft-asm.json, with every part inside it. One file carries the whole assembly, so you can send it on its own.
Saving is a download. Your browser puts the file in its downloads folder, or asks where to put it if you set it to ask. Saving again makes a new download; the browser may name it Part1 (1).partcraft.json rather than replace the old one. Rename or move files in Finder / File Explorer / your file manager as you like.
Characters other than letters, digits, spaces, _, . and - in the part name become _ in the file name.
More about where downloads go and how to keep files safe: Where your files go.
Exporting
The Export menu writes other formats. Each is a download, named after the part.
| Menu item | File | What is in it |
|---|---|---|
| STL, for 3D printing | <name>.stl | Binary STL of the solid's triangles, millimeters, Z up |
| 3MF, for 3D printing | <name>.3mf | 3MF with the solid as one object, millimeters, Z up |
| STEP AP242 (exact solid) | <name>.step | The exact solid with true cylinders, cones, tori and fillets, as STEP AP242. Millimeters, Z up. Needs the exact kernel |
| STEP AP214 (exact solid) | <name>.step | The same, as STEP AP214, for programs that prefer it |
| STEP (faceted, mesh kernel) | <name>.step | A solid made of flat faces from the mesh: round surfaces are many small flat facets. Millimeters, in PartCraft's own axes (Y up). For when the exact kernel is not available |
| DXF of the sketch or flat face | <name> - <sketch>.dxf or <name> - face.dxf | DXF R12. A sketch: lines, arcs, circles and points in the sketch's own coordinates, on layers PROFILE, CONSTRUCTION and POINTS. A picked flat face: its outlines as closed polylines (round edges as their facets) |
| Drawing (PDF): views, section, detail, GD&T | <name> - drawing.pdf | The A3 drawing sheet: three views, isometric, section and detail if set, overall sizes, GD&T symbols, title block |
- Exports are of the part on screen. Export is turned off in an assembly; there is no assembly export yet.
- STL, 3MF and the face DXF are always made of facets. The Curves setting (in the right panel with nothing selected) sets how fine they are, from 32 to 256 facets per turn. Choose Fine or Very fine before exporting STL or 3MF for a smooth print.
- The PDF drawing uses the reader's built-in Helvetica font. Characters it cannot show print as "?".
Step by step: Export for printing, STEP and DXF and Make a drawing sheet.
Unsaved work
- PartCraft does not save on its own. Save often.
- If you try to close the tab or reload with unsaved changes, the browser asks "Leave site?". That is the browser's own box; PartCraft cannot change its wording.
- New, Open and closing an assembly ask before discarding unsaved changes.
Online and offline
Everything happens on your computer: the solid kernels (WebAssembly programs) are downloaded with the app and build geometry locally, and files are read from and written to your disk. No part data goes over the network. The exact kernel is a bigger download that finishes after the app opens; see The exact kernel and the mesh kernel.
To work with no connection at all, save PartCraft for offline use while you are online: choose Save for offline in the app bar and wait while it counts ("Saving 40 of 212") until it says Offline ready. The saved copy includes the 3D library, the mesh kernel and the exact OpenCascade kernel, about 27 MB in all (the exact kernel is most of it), so afterwards fillets, chamfers, shells, STEP import and export, and drawings all work offline. If it says Could not save, click it to try again while online; Offline not available means this browser window cannot keep a copy (private windows and some managed computers). With the copy saved, clicking Offline ready offers Save again (get the newest version) and Remove the offline copy. Details: Working offline.
Online
You are online. Even without saving for offline use, once PartCraft has loaded and the status bar chip says "Exact kernel", you can keep working if the connection drops. Just do not reload the page until you are back online.
Offline
You are offline. If PartCraft is already open, keep working; saving and exporting still work. If the exact kernel had not finished loading, STEP import, exact STEP export, fillets, chamfers and shells wait until you are online. If the app bar says Offline ready, PartCraft also opens from scratch with no connection; otherwise do not reload this tab.
Differences between browsers
- Downloads. Each browser has its own downloads folder and its own way of asking. If a browser asks whether this site may download files, allow it, or saving and exporting cannot work.
- Drag and drop of a file onto the view works in Chrome, Edge, Firefox and Safari.
- Files from a phone or tablet. On iPhone and iPad, Open shows the Files app; saved files go to Files, Downloads. On Android they go to the Downloads folder.
There is no difference in what the files contain between browsers or operating systems.