Design and file guide for 3D printing

The first step to get the best results when 3D printing is to optimize your design. Here you will find a guide to design, prepare and export your model for the 3D printing process.

Content:

Check your design
Prepare multiple pieces/big models
Save/Export files for 3D printing

Would you like us to design for you?

If you would like us to draw on the computer for you, you could send us a sketch of your project and a description about size, amount, and wished material.

The file can be any file type that we can read, such as a text file with a written description, a scan of a hand sketch (JPG, GIF, BMP, PDF), a mock-up in Word, Paint, or Excel, etc.

To directly request a quote that includes file creation, please submit your file in the quote request form and mention that you need us to draw your parts. File creation costs are listed at our 3D printing pricing page.

Design check list

How to design for 3D printing? We have collected the 11 most important things to consider when designing your models.

UNITS: Set your units in mm and scale 1:1

WATER-TIGHT MESHES: Models to 3D print need to be constituted of water-tight meshes. Any hole in the model, non-connected or overlapped surfaces, have to be removed. If you imagine to fill your model with water it should not leak. Free softwares, such as Netfabb or Meshlab, make it easy to check for errors or holes in your model.

REMOVE NON-MANIFOLD GEOMETRY: A model designed for 3D printing has uniquely determined geometric elements. This means that every vertex belongs to a single solid, an edge belongs always to two surfaces and a face belongs to a single solid element.

PRINTING MATERIAL: Different materials have, of course, different characteristics, and they print differently also. Some polymers can be printed in very thin layers, while other ones need an increased layer thickness to succeed. One material allows for printing at high speed, while the other one will only work at a very low speed. It is always important to keep in mind the material we are going to print with and its properties.

SUPPORTS: The function of supports is to hold up overhanging parts of the model during the printing process. where it is nothing to build on. These structures are helpers that are 3D printed together with the 3D model, where overhanging details are present. Afterwards, they are removed and the model is cleaned up.
It is efficient to design avoiding unsafe overhangs because supports can be difficult to remove from complex prints or they might leave marks on the model.

45° – RULE: This comes in order to minimize the need of supports. Generally speaking, overhangs within a 45 degrees slope are safe to print (only in some cases is possible to overcome this value). Anything greater than this value require supports.

BRIDGING: When a overhang stands in between two towers like a ‘bridge’, it is possible to benefit from the bridging property of FDM 3D printing. If the printer has a supported point to start from and a supported one to join, then it will bridge an open air gap successfully. The length we can safely bridge depends on the material’s characteristics, the printing settings, and the model’s shape.

TOLERANCE: Interlocking or moving parts require clearance between one another to work. The distance you need to leave between the parts depends on their functionality. Mechanical parts, such as gears or gearboxes, need small clearance to work, while interlocking parts need more of it. In general the minimum suggested clearance is 0.4mm, a smaller tolerance will let the parts fuse together.

WARPING: There are different polymer used for 3D printing and of them For some polymers used in 3D printing, it is important to consider the tendency to shrink when they cool down.

WALL THICKNESS: The wall thickness is mostly important for the durability of a print. It is not advisable to design walls thinner than 1mm, because these would constitute fragile parts.

POST PROCESSING: Some materials can be post-produced to obtain different kinds of finishing. For instance, parts made in ABS can be smoothed if treated with acetone vapors. Composite materials can be sanded, stained and/or polished. If you plan on post-producing your models, be sure to add extra walls into your design.

Multiple pieces / Big models

Sometimes the dimensions of our design are bigger than the supported printing volume. In this cases, we can 3D print the model in parts and weld them afterwards.

Depending on the adopted material and technology, we can work within the following volumes:

ENCLOSING VOLUMES (millimeters)

MARGIN: Always leave 5mm all around the building plate in order to allow available surface for helpers (Brim/Skirt/Raft)

ASSEMBLY: When the design is made of more components, they have to be individually exported in single files.

Save/Export

A large number of modeling software is available for 3D designing our models. Whether they are free or not, they are generally able to export in a format suitable for 3D printing.

Here below you will find a list of the file formats we can work with.