Generate
Describe the function, dimensions and manufacturing intent.
Product documentation
PurCad Guide
A practical product handbook for turning a measured requirement into editable, checked and exportable CAD in PurCad.
Inspect
Review geometry, dimension sources and assumptions.
Deliver
Resolve blockers and download the format the next tool needs.
Start here
The shortest path to a useful part
Workflow
PurCad workflows
Generate from a requirement
Work from references
Edit without losing intent
Deliver the right CAD file
Validate before delivery
Functional part use cases
Create the small workshop tool your process is missingConnect objects that were never designed to meetTurn a repeatable workshop operation into a measured fixtureReplace the function, not just the silhouetteWrap a component without hiding access, heat or assembly needsDesign storage around the objects and space you actually haveRoute a real cable through a clip sized for the actual installationCreate the required support height and mounting pattern for your assembly
Getting started
Studio basics
PurCad keeps the whole job in one workspace: the request and references on the left, the model in the center, and editable data on the right. The history bar below keeps every generated or restored version.
Request + files3D viewportSizes · Parts · Check · DownloadVersion history
Closing or switching a panel does not delete work.The current project, versions and exports stay in the Library until you delete the project.
Back to top ↑Your first useful model
- State the job. Say what the part holds, connects, protects or aligns.
- Add critical measurements. Include mating diameters, hole spacing, clearances and the available envelope.
- Generate a draft. Start with Fast for exploration; use higher quality after the requirements are stable.
- Inspect before download. Review Sizes, Check and the physical fit assumptions.
Example request
Back to top ↑Wall hook, 30 mm wide plate, two 5 mm holes 50 mm apart, 3 mm wall, rounded exposed edges, for light indoor loads.Projects and Library
Each card represents one project. Its preview, overall size, file state, validation outcome and risk class let you decide what is safe to reopen without guessing.
- Check passed
- The current version has no blocking geometry issue. It is not a certification of strength or fitness.
- Light duty
- The declared use has a low risk category. Real loads, material and mounting still need to be verified.
- No files yet
- No export package has been prepared for the current project.
Generate
Write a buildable request
Describe engineering intent, not just appearance. A useful request usually contains five things:
| Include | Example |
|---|---|
| Function | Holds a 22 mm tube against a wall |
| Interfaces | Two M5 screws, 50 mm apart |
| Critical sizes | 22.4 mm bore, 3 mm wall |
| Manufacturing | FDM print, no support inside the bore |
| Risk and load | Indoor, static, under 2 kg |
Do not hide uncertainty.Mark guessed values as estimates. PurCad can expose them as assumptions; it cannot recover a measurement that was never supplied.
Back to top ↑Photos, measurements and scale
Add photos when they communicate shape or installation context better than text. Images are approximate visual references, not exact geometry. Enter a known length from the same plane as the feature you care about.
- Use even light and avoid perspective-heavy close-ups.
- Include front, side and mating-surface views when possible.
- Put a ruler, known fastener or measured edge in the image.
- Confirm photo-derived fit with direct measurements and a low-cost prototype.
Quality modes and credits
Quality controls the minimum compute budget for a request. Credits are reserved before generation and settled after the actual provider work is known.
| Mode | Use it for | Floor |
|---|---|---|
| Fast | Early concepts and focused revisions | 25 credits |
| Balanced | Normal functional parts | 50 credits |
| Careful | Complex geometry and final refinement | 85 credits |
Current packs: $5 / 100 credits (up to 4 Fast), $25 / 650 (26 Fast, 13 Balanced or 7 Careful), and $100 / 3,000 (120 Fast, 60 Balanced or 35 Careful). These are maximums at the quality floor; actual provider spend may reduce the count.
Back to top ↑While PurCad is building
The generation panel moves through understanding, building and checking. Keep the project open until the request finishes. A successful job creates a new version; a failed job leaves the previous version current and reports the error.
A project version is the recovery boundary.Generate or restore a known-good version before a risky change so you can compare results without losing work.
Back to top ↑Inspect & edit
Viewport navigation
| Action | Control |
|---|---|
| Orbit | Drag |
| Pan | Right-drag or Shift + drag |
| Zoom | Scroll, + or − |
| Step rotation | Arrow keys |
| Reset view | 0 or Reset view |
| Axis view | Click X, Y or Z on the view cube |
Sizes, sources and confidence
The Sizes tab separates values you supplied from reasonable defaults inferred by the model. Edit the number, not the label; the unit remains millimeters.
- Set by you
- Directly supplied in the request or edited in the panel.
- Reasonable default
- Inferred without a direct measurement. Treat it as a decision to review.
- Confident / usually OK
- Model confidence, not metrology. It never replaces a caliper or test fit.
Section and measurement modes
Solid is the normal shaded view. Section cuts the preview along X, Y or Z and can hide either side. Measure lets you select a visible edge and read its length. Use these modes to inspect the generated result; edit authoritative dimensions in Sizes.
Back to top ↑Versions, rollback and restore
| Action | What happens |
|---|---|
| View | Inspect an older version without changing the project head. |
| Make current | Move the current pointer to an existing version without deleting later versions. |
| Restore as new | Create a new version from the selected historical state and continue from it. |
Validate & export
Checks, assumptions and risk
Check combines geometry results, blocking issues, warnings, the declared risk category and model assumptions. Resolve blocking issues before export and read every assumption that affects fit, wall thickness or mounting.
Check passed is not engineering certification.A valid solid does not prove that the material, load path, safety factor or mounting is suitable. Loaded, rotating, hot, overhead or human-supporting parts require qualified review and physical testing.
Back to top ↑Choose the right download
| Format | Best for |
|---|---|
| STEP | Mechanical CAD exchange, inspection and CAM |
| STL | Broad slicer compatibility |
| 3MF | Modern packaged print workflows |
| OBJ | Mesh tools that specifically require OBJ |
Select the formats in Download, then prepare the export package. Downloads are tied to the selected project version.
Back to top ↑Reference
Shortcuts
| Key | Action |
|---|---|
| ← ↑ ↓ → | Rotate in fixed steps |
| + / − | Zoom in / out |
| 0 | Reset the camera |
| ? | Open the shortcut overlay |
| / | Focus documentation search |
| Escape | Close an open dialog |
If something goes wrong
- The model does not match the request
- Make the next request focused: name one incorrect feature, its intended relationship and an exact size.
- Photo result has the wrong scale
- Attach a reference with a known length in the same plane and enter that length.
- Export is unavailable
- Open Check, resolve blocking geometry issues, then prepare the files again.
- A size changed the wrong feature
- Return to a known-good version and describe the intended feature by function and location.
- Generation failed
- Your previous version remains current. Retry with a smaller, clearer change; credits settle according to the recorded request outcome.
Basic CAD words
- Solid
- A closed 3D body suitable for CAD operations.
- Mesh
- A surface made from triangles; common in scans and print exports.
- Parameter
- A named editable value that controls geometry.
- Clearance
- Intentional space between mating parts.
- Bounding box
- The overall X × Y × Z size of the model.
- Assumption
- A design decision made without a direct measurement.