Process / before you send
Give the part enough context to be read properly
STEP is preferred because it gives us editable geometry when a fit, interface or export needs attention without forcing us to re-derive your design intent. STL and 3MF are also welcome. If you have no CAD, describe the part in prose: what it connects to, what it must withstand, and which features matter.
Formats, units and origin
A usable file arrives with enough context to be read correctly.
Send STEP where possible. It retains solids and surfaces that can be inspected and, when agreed with you, adjusted for fit. STL is a triangle mesh and works well when it is clean, scaled correctly and sufficiently detailed. 3MF can carry mesh data alongside useful build context. We review all three against the same physical question: does this represent the part you intend to make?
State the units. STL in particular may arrive without reliable unit information, and a good part at the wrong scale is still the wrong part. Keep the model near a purposeful origin and orient it consistently with any drawing or assembly reference. We may choose a different build orientation, but we should not have to guess which face you called the top.
Pre-send checklist
A short check prevents avoidable questions after upload.
- 01The file opens as the intended part, not an empty scene or an assembly export with hidden bodies.
- 02Units are stated in the file name, drawing or message.
- 03The origin and orientation are intentional, especially if the part relates to a mating assembly.
- 04The supplied revision is identified and matches the drawing or message.
- 05Bodies intended to be separate are separate, and bodies intended to be one part are joined.
- 06Wall, hole and clearance features have been checked against the chosen nozzle guidance.
- 07Mating parts or a clear description of the mate are included for fit-critical features.
- 08The intended service environment and loads are described in plain language.
- 09Visible faces and surfaces that must not receive support are identified.
- 10You have confirmed that you are entitled to send the geometry for manufacture.
Ten defects that delay a useful answer
The review should find the manufacturing question, not basic file damage.
| Defect | What it means | How to fix it | Common cause |
|---|---|---|---|
| Open surface | The model does not enclose a volume. | Repair or cap the missing faces in the CAD or mesh tool. | An incomplete export or deleted face. |
| Non-manifold edge | More than two faces meet at an edge, so inside and outside are ambiguous. | Split the conflicting geometry and rebuild the join as a solid. | Intersecting shells or an invalid boolean. |
| Self-intersection | The model passes through itself. | Resolve the overlap, then export a fresh solid or mesh. | Thin features folded into adjacent geometry. |
| Reversed normals | Some faces point inward when they should point outward. | Recalculate normals after repairing the mesh. | A flipped shell during editing or conversion. |
| Duplicate shell | Two bodies occupy the same or nearly the same space. | Delete the duplicate and verify the remaining body. | Repeated export, mirror or copy operation. |
| Disconnected fragment | A small body is not connected to the intended part. | Join it deliberately or remove it. | Construction geometry included in export. |
| Unclear units | The numerical size has no dependable scale. | State units in the file name and message, then re-export if needed. | A format that does not retain unit metadata. |
| Faceting | A curved surface is represented by triangles too coarse for its intended shape. | Export with a finer mesh setting or send the STEP source. | A low-resolution STL export. |
| Zero-thickness feature | A surface has no printable volume. | Give it a real wall based on the intended nozzle. | Sketch or surface geometry exported as a solid. |
| Unmerged assembly | Parts that should form one body remain overlapping solids. | Boolean-union them, or label them as separate pieces. | An assembly export without a final merge. |
A flag asks for a decision. A warning keeps the decision visible.
Both statuses keep the manufacturing consequence in view.
A flagged issue stops the path to manufacture until we have contacted you. An open body, unclear scale, unprintable zero-thickness feature or part that needs a segmentation decision belongs here. A warning may leave the part feasible, but it may affect visible finish, build direction, support contact or assembly behaviour. It is reported so you can decide whether the trade-off is acceptable.
Neither status is a judgment on the quality of your design. Both are a way of making the manufacturing consequence explicit before it is made permanent.
Start with the actual part
Send the file, or explain the requirement and the environment it must serve. We will read it before we make anything.