How to prepare your 3D printing project: the complete guide
Everything you need to know to prepare a 3D printing project: accepted files (STL, STEP, OBJ), dimensions, tolerances, material choice. Step-by-step guide to succeed with your order.
You have a 3D printing project but don't know where to start? Don't panic. Whether you have a ready-to-use 3D file or just an idea sketched on a napkin, this guide explains step by step how to prepare your request for a perfect result. For real-world repair and custom object examples, see 3D printing for individuals.
An accurate quote depends on real use, critical dimensions and photos with scale — spend two minutes noting them and you'll save a round trip.
Case 1: You already have a 3D file
This is the simplest case. You've modeled your part yourself or downloaded a file from a platform like Thingiverse, Printables or Cults. Here are the formats we accept:
- STL: the standard 3D printing format. The most common and compatible.
- STEP / STP: parametric CAD format. Ideal as it preserves exact dimensions and lets us modify the part if needed.
- OBJ: 3D format with textures. Used for decorative parts.
- 3MF: modern format including colors, materials and metadata.
- Native CAD files: Fusion 360, SolidWorks, FreeCAD, Blender — send us your source file, we can work with it.
Important checks before sending
- Units: verify your model is in millimeters (mm). A file in inches will produce a part 25x too large.
- Wall thickness: minimum 1mm for FDM, 0.5mm for SLA. Walls that are too thin won't hold.
- Maximum size: our FDM build plate accepts parts up to 350x350x400mm. Larger ones are split and assembled.
- Closed geometry: the model must be "watertight" (no holes in the mesh). We fix minor errors for free.
Case 2: You don't have a 3D file
This is the most common case for individuals, and it's not a problem. At NC Factory, we have an integrated design office that can create the file for you. Here's how to help us work efficiently — the same approach applies to marine parts and automotive parts when you have no CAD file:
If you have the original part (even broken)
- Take multiple photos from different angles
- Place a ruler or coin next to it for scale
- Photograph important details: holes, notches, clips, attachment points
- If the part is broken into pieces, gather all pieces and photograph the set
If you're starting from an idea
- Make a sketch (even rough) with important dimensions
- Describe the part's function: where will it be mounted? What forces will it endure?
- Specify the environment: indoor, outdoor, heat, humidity, food contact
- Indicate critical dimensions (those that must be exact)
How to choose the right material?
Generally, we recommend the material based on the use you describe. But here are the broad guidelines:
- Standard indoor use → PETG (strong, durable, food-safe)
- Outdoor use → ASA (UV and weather resistant)
- Strong mechanical stress → Nylon PA6 or PA6-CF
- Flexible part → TPU (rubber-like flexibility)
- High precision / aesthetics → SLA Resin
Check our complete 3D printing materials guide for further details. To see if 3D is the right process vs CNC or injection, read 3D printing vs traditional manufacturing.
If you're torn between two materials, describe max temperature, UV exposure and impacts — we'll decide for you.
How long does it take?
- Quote: within 24h after receiving your request
- Modeling (if needed): 1 to 3 days depending on complexity
- Printing: 24 to 48h for most parts
- Post-processing (if needed): sanding, painting, assembly — 1 to 3 additional days
- Delivery: immediate pickup at workshop (Antibes) or next-day delivery in the 06
For urgent needs, we offer a 24h express service with production priority.
Most common mistakes
Incomplete requests slow quotes or yield wrongly sized parts. Avoid:
- File in inches instead of millimeters — the part prints huge or tiny
- Photos without scale — we can't validate mm-level dimensions
- Forgetting the environment (sun, hot water, engine) — wrong default material
- Non-manifold mesh with ignored holes — print risk if not flagged
- Tight tolerances not stated for assemblies — fit too loose or too tight
One sentence on function ("clips onto a 20mm bar", "must survive 80°C") beats a long email without context.
Post-processing: available finishes
The part off the machine isn't always the final step. We can provide:
- Sanding and smoothing of FDM layer lines for a softer feel
- Primer and paint to unify color or match furniture / vehicle trim
- Assembly of split parts (large format) with glue or inserts
- Deburring and dimensional check before shipping
- SLA resin: wash, UV post-cure and light sanding for near-injection finish
Mention in the quote if you need a visible finish (decor, yacht, auto): we'll adjust wall thickness and orientation accordingly.
Submit your project to NC Factory
Three ways to contact us:
- Quote form on our website — the most comprehensive method
- WhatsApp (+33 7 63 98 46 64) — perfect for quickly sending a photo
- Email (contact@nc-factory.com) — for large files and detailed projects
Frequently asked questions
Prefer STEP/STP or STL in mm; we also accept 3MF, OBJ and native CAD files.
Yes: photos + dimensions or the physical part are enough for us to model it.
Minor mesh fixes are often included; major remodeling is quoted.
Not necessarily: describe use; we suggest the right polymer (see materials guide).
Yes: 06 department priority; options for the rest of France depending on parcel size.
Whatever your starting point (3D file, photo, sketch or simple idea), we transform your need into a concrete part. Free quote, no commitment, within 24h. Workshop in Antibes. Express delivery with installation in the Alpes-Maritimes, home delivery or relay point pickup throughout France.
