Key takeaways
- Always send both a 3D model (STEP) and a 2D drawing (PDF) with tolerances.
- State quantities for the first order and the expected annual volume.
- Spell out inspection, certificates and shipping terms — they affect price.
The checklist
| Item | What to include |
|---|---|
| 3D model | STEP (or native CAD) for every part, matching the drawing revision |
| 2D drawing | PDF with dimensions, tolerances, GD&T, thread and weld callouts |
| Material | Grade and temper, e.g. 6061-T6, 304 stainless, S355 or A36 steel |
| Finish | Anodising, powder coat colour, galvanising, plating, surface roughness |
| Quantity | First order quantity plus expected annual volume |
| Inspection | Critical dimensions, first-article report, material certificates |
| Packaging | Any special protection, labelling or kitting |
| Delivery | Delivery address, shipping term (DAP, DDP, FCA) and required date |
| Customs | HS / HTS code if known, and the importer of record |
Common mistakes that slow quotes down
- Sending only a PDF of a complex part, so the supplier has to model it.
- Sending only a 3D model, with no tolerances or finish information.
- Drawing and model at different revisions.
- "Tight tolerances everywhere" — it multiplies inspection time and cost.
- No quantity, or only a single quantity when you will order in several batches.
If you only have a sketch
You can still get a useful answer. Send a sketch with the main dimensions, the material, the quantity and a few lines about what the part does. An engineer can then propose a design and a budget price, and produce the drawings if needed. Our mechanical design service covers exactly this.
Protecting your files
Ask the supplier to sign your NDA before you upload, and ask which partners will see the files. At Mechline Engineering files are shared only with the production partners that make your parts.
Before sending, run through our DFM checklist — it often lowers the quoted price.
Frequently asked questions
Which file format is best for a quote?
STEP for the 3D model plus a PDF drawing with tolerances. DXF is useful for flat sheet metal parts.
How fast can I get a quote?
With complete information, Mechline Engineering replies with price, lead time and engineering notes within 24 hours.
More guides
- Contract manufacturing in Turkey: a practical guide for US and European buyers
- Manufacturing in Turkey vs China: cost, lead time and risk compared
- How to outsource mechanical design without losing control
- DFM checklist for CNC machined, sheet metal and welded parts
- When do you need FEA? A practical guide for product teams