Thursday, February 5, 2015

How to Download Objects From the Internet

Today I will go thru step by step on how to download a physical object from the internet.

Note:  I will be using a 3D printer to make this object.  3D printers will make this file, although a small milling machine will make as well and the milling machine will be more accurate.

That said there are undercuts that make the necessary addition of registration pins if you are to make this with a 3 axis mill.

With a 3D printer there are no tooling changes.

First thing we need is a file.  Thingiverse is the most popular for 3D printers, but quality of the files and availability of useful items is rather limited compared to Traceparts.

TraceParts exists as a way for manufacturers to share their design files in the hopes that engineers will use those files and then order the parts from that particular supplier.

Generally these files are not made for 3D printing, but with care you can mod the file for printing and get a acceptable result.  Another cool thing is to download things like switches and hardware that you can print out to use as test pieces.  For example you are doing a mockup of a machine with some specialty switches, fittings etc.  You can download the parts, print them out and while they do not physically work, you did not spend the money buying something (and waiting for it to arrive) just to see what it would look like or how it would work in the real world.

Traceparts CAD files

Here is a example of a gear we would like to download

 We download this file and save to the computer

We then open the file in our CAD software.  In this case DesignSpark Mechanical
We set the export options in the file.  In this case we are using 0,9 degrees.  Since .stl files are a mesh that means that it is not a true curve, rather a polygonal mesh.  So we make the polygon angles small so that there are no visible facets in the finished item.

We open the file in our printer control and slicer software.  In this case Simplify3D

We set our resolution, print speed, infill and other settings

We pre-heat the 3D printer and then click on the begin printing