How to Upload a Part

Last updated September 26, 2026

This guide covers the full flow for quoting a single part on OpusFab, from dropping the file to saving the quote. If you are uploading several parts at once, see multi-part uploads and BOM import.

Before you start

You need a STEP file (.stp or .step) of your part. If you are not sure what that is or how to export one, read what is a STEP file first.

The upload flow

  1. Open the dashboard and go to the upload screen.
  2. Drag your STEP file into the dropzone, or click to browse for it on your computer.
  3. Wait a few seconds while the file uploads and is analyzed. A single file opens the part configuration screen automatically.

Configure the part

The configuration screen shows a 3D preview of your part on one side and the quoting options on the other. The price updates live as you change any option.

  1. Check the preview. Rotate the model and confirm the geometry and dimensions look right. If the part looks the wrong size, re-export from your CAD tool with the correct units.
  2. Pick a process. For example CNC Machining (milling), CNC Turning, SLA Resin, SLS, or metal 3D printing (DMLS/SLM). If you are not sure which fits your part, see choosing a process.
  3. Pick a material. The list only shows materials valid for the process you selected, such as 6061-T6 Aluminum or 7075-T6 Aluminum for CNC, or Standard Resin for SLA. The live list in the editor is always the current one.
  4. Pick a finish. Options depend on the process, for example Raw (As-Machined) for CNC parts or As Printed for 3D printed parts, plus bead blast, anodizing, powder coating, and PVD where available. See the surface finishes overview for what each one does.
  5. Set the quantity. Instant quotes cover 1 to 100 units per part. The price recalculates immediately, and you will usually see the unit price drop as quantity rises.

Read the price and DFM feedback

The instant price is shown on the same screen, broken out so you can see what you are paying for. Understanding your quote explains each component.

Automated DFM (design for manufacturability) analysis runs on every upload. If the analysis finds a potential issue, such as an internal corner radius below the current 0.5mm warn threshold, you will see a DFM warning for the part. A warning does not block your order. It is a flag that a feature may add cost or risk, and it is worth reviewing before you commit. See the DFM overview for how to read these.

Save the quote

Click save to keep the configured quote in your dashboard. You can come back later, change any option, and the price recalculates instantly. Nothing is charged until you check out, so saving a quote is a safe way to compare materials, finishes, and quantities.

When you are happy with the configuration, continue to checkout and payment.

Parts that cannot be quoted instantly

Two cases route out of the instant quote flow:

  • Quantities above 100 units.
  • A STEP file containing an assembly with multiple parts in one file.

In either case you can request a custom quote from the upload or edit screen. The part shows as “Requested” briefly, leaves the instant quote list, and the sales team follows up by email. See custom quotes for details.