3D Printing file standards? pre-flight checklist?

[marlin]

Dear 3D printer community,

We are anticipating a client request for their model(s) to be printed in the 3D format.

We will not be managing the print relationship after we submit the final geometry file(s).


What advice can you offer to make this process a success?

Is there a minimum / maximum requirement(s) for the mesh?

Is there a "standard file requirement" or a pre-flight checklist before 3D printing? url? app?

Does anyone happen to know any quality 3D printers / service providers that also print RGB data as well?


I realize that there are many questions above, any input on this matter would be greatly appreciated.

thank you to the community, I appreciate the professional standards and great information in this forum

Marlin.

[chrisd]

Hi Marlin,

1) The model must enclose a volume. If you have a single surface like a landform, it would have to be thickened (shelled).

In general, you will want to shell objects unless they are very small, since making an object solid can be very expensive because it uses much more material.

A small opening in the shell is generally needed to empty the unfused powder. Don't confuse this with a hole in the mesh, which is a geometry problem

2) The volume cannot have any holes/cracks in the mesh. Edges must be shared by 2 triangles, if not, the object is non-manifold and unprintable.

3) No intersecting volumes or intersecting triangles

4) Build volume of the printer limits the size. Larger objects must be printed in sections.

I would recommend Netfabb Basic, which is free, to check your models. It also has some repair functions. Netfabb also has a cloud service, which has a free option, for checking and/or repairing files, but you have to upload your file.

[marlin]

@Chrisd.
thank you! very interesting and useful info. appreciate your professional opinion.

3D printer with RGB - rebuilding the surface of a painting ...
Somebody sent me this link: Anyone know the details? Article doesn't really state very much. There is a vid, but not much more ...

http://www.engadget.com/2013/09/24/3d-art-printer/

[ech3dt]

following tips will may help you.

Beginning with the End - Where does a typical desktop publishing project begin? Dumb question? Perhaps not. For all practical purposes, the information gathering process starts at the end, with the printing process. If you're new to desktop publishing, this article will explain some of the technical aspects of design you may not have considered. If you're an old pro, it might remind you of some of the production steps we (I include myself here) sometimes forget.

Checklist to Success - Prevention is better than cure, and nowhere more so than in desktop publishing. Learn to preflight your design documents before they cause trouble down at the bureau or presses.

Printing Checklist - Printing is a complex, highly technical process that must be carefully planned and executed to get the desired results. Many things can go wrong, and even small problems can cause delays and cost overruns.

Design Guide For Print : Submitting Files For Print - We've learned that by streamlining the prepress process we are able to pass significant savings onto our customers. Our prepress guidelines also let us bypass common pitfalls associated with preparing digital artwork for print such as embedding fonts, and unlinked images.

Environmentally Preferrable Printing Checklist - Some organizations develop simple checklists to assist purchasers in designing environmentally preferable print jobs. These checklists help organizations save money, reduce waste and protect the environment. A copy-ready checklist has been provided for you to use as is, or modify to fit your organization's needs.

Free Digital File Preflight Test - Here are some of the file errors that commercial printers look for when you send them a file...it is good for you, the graphic designer, to know what to look for so you can save on any extra costs.

3d printing service INDIA

[Limpopo_River]

I'd echo all of ChrisD's list, and would also recommend decimating the mesh to fewer than ~100K polygons.  The limit on the number of polygons will depend on the type of 3D printer and the software used to slice the model into layers to produce G-code instructions for the printer.  Larger meshes can take a very long time to slice, especially if the resolution of the layers is very thin.  I found that Meshlab (open source) and Meshmixer (free) had useful tools for extruding a surface into a printable volume, performing minor edits and repairs, and for checking the mesh for the kinds of errors that ChrisD also mentioned. 

I'll offer some additional thoughts based on my admittedly limited experience using PLA printers (others' experience may differ and feel free to correct any of the following that could be out-of-date).  An alternative to shelling is to print the object with a honeycomb-like internal structure that provides both structural rigidity and reduces the volume of material in the print.  This can usually be specified when you set the parameters in the slicer software, so you don't necessarily have to produce a model with a shell before you give it to the printer; you can simply provide a "water-tight" 3D mesh.  The slicer software will allow you to choose the amount of open space and the type of internal structure.  The 3D printing service will often have suggestions for parameters to use, since printers vary.  Many 3D printers and slicer software will accept either an STL or OBJ file.  If you produce an OBJ file, you'll also likely need to provide an MTL file that describes material properties for the mesh. 

Color (RGB) printing typically requires more expensive 3D printers and different materials than single-filament PLA printers.  Some filament printers have multiple print heads to allow printing with different colors of filaments, but I don't think they can reproduce mixtures of RGB color.  Printing with ABS has some qualities that PLA lacks, but it's typically a bit more expensive than PLA and it requires a 3D printer with a heated bed to be successful.  The next step up for color printing is a gypsum-like material, often described somewhat misleadingly as "sandstone."  You'll see examples of this material on Shapeways.com, but there are other simllar vendors.

You'll find a variety of 3D printing services on 3DHubs.com (an Uber-like service), for example.  Browsing this site is a good way to learn about the variety of available printers, materials, and costs, which can vary a lot.  I searched a while before I found a local person who provided a high-quality PLA print of an 100-percent scale 3D model that was about 10 x 3 x 6 inches (180 cubic inches) for what I considered a reasonable cost.   

Best of luck,
LR

[bigben]

Meshmixer started as more of a 3D sculpting app that grew additional features pertaining to 3D printing. Autodesk now use it as a "printer driver" for some of their design apps. We ran a modest printing service at my uni for a couple of years and this became our tool of choice for checking clients' models. 
Good analysis and repair tools.
If the model is a complete mess it has a "shrink wrap" function that basically wraps a new mesh around the model to create a lower res but watertight mesh.
Centre of gravity calculations (will it stand up)
Tools for shelling and placing drainage holes

For mesh resolution it depends on the printer.  For high res printers we've used 100mb stl files without any problem, but other printers can freak out. Check the requirements with your print service. Meshmixer started to freak out a bit if we gave it more tha 5million polygons so that was our de facto max.  Others use ZBrush which is very good but a bit quirky to get used to.