3d printing

Quelab goes to TEDxABQ


Going to TEDxABQ on Saturday September 17? So are we! Drop by the Quelab booth — outdoors on the Civic Plaza for the “audience engagement” session from 10 am to 1 pm, and indoors during the Speaker Sessions from 1 pm on. Learn more about our makerspace and how you can start making at Quelab!

We will have live demonstrations of a 3d printer, a wood lathe and a hand-made bowling lane. (I’m guessing the convention center isn’t going to let us take ALL of our fun toys inside, so arrive early if you’d like to see everything!)   We will also be giving away some laser-cut gears (made on Quelab’s laser cutter — some of the gears are being cut by the laser head in the photo above), which are part of a geared back-scratcher (also a great fidget!) design that you can make yourself with the free design files at http://www.thingiverse.com/thing:1766894. If you don’t have a 3d printer or laser cutter, or would like to learn how to use them, come visit us at Quelab and we can help you!  Our open hacknights are every Sunday and Tuesday from 7-10 PM at Quelab, 680 Haines Ave NW, Albuquerque NM, 87102. Tours at 7:30 and 8:30.

Special thanks to Kris Hardy with Albuquerque Software for custom laser cutter and 3d printer design, and donating the materials and time for making the gears and backscratchers!

Help! My GCode is borked! 1

Do you have prints that don’t print?A pronterface that looks wrongterface? Well, you might have a bad mesh.

I ran into this when attempting to slice a whistle from Thingiverse: Slic3r would give me the ominous “Non-Manifold mesh” message and the printer would spaz out.

In order to undertand what’s going on, there should be a little information on how tools like slic3r work. Slic3r and other G-code generators tend to work on the values of face “normals” — the direction the face, well, “faces.” Let’s take our whistle for example: As downloaded from Thingiverse, it looks like this:

Bad STL file from Thingiverse

The tool I use is ModuleWorks STLView (also for android!) which allows us to show the face normals (green lines) and faces which face the wrong way (gold surfaces). Slic3r will produce some very, very strange GCode for this model:

Ugly GCode as a result of bad mesh

The tool here is the RepRap GCode Simlulator from opencode.eu.The source is included, and depends on openGL. This lets us see what the actual path for each layer of the model looks like.

So what do we do? First: don’t panic. Most of the horrible problems with ugly looking meshes can be fixed — all it takes is some time with the NetFabb cloud service. NetFabb produces a commercial 3D printer, but also runs a cloud service at http://cloud.netfabb.com/ which allows you to upload STL meshes and download the fixed version.

Here’s what the model and resulting GCode look like afterwards:

Fixed, good model with all its normals pointing out

Good GCode as a result of a clean mesh