This weeks Robot Hospital! Episode Two is truly reaching for new heights of pre-production here at the BotCave! Those crazy live-stream days are fading into memory~ We have a great instructional segment from Ethan, who teaches you proper Stepper Driver Calibration, and later he covers the 3D Printing blogosphere in his weekly “Blog Rap.” Griffin and Marty demonstrate connecting the Unicorn to the Thing-O-Matic in fine style, and Matt details some great, and not so great, ideas for finishing techniques to use on your printed objects. We have a second interview with Marek from BeatBots, and the Keepon stops by and teaches robots everywhere how to hold space on the dance floor. Isaac drops in to discuss MakerBot Water Soluble PVA, and debuts version one of the Robot Hospital! intro! We’re going for it with this episode, it’s a new benchmark for what’s to come! Musical intro chops from “The Insider”

Mouse Ears Tabs by Zach

Once upon a time, far away in the country of Brookland, in the non-coexistent special universe of the Greater New York Area, there lived an engineer called the Zach. The Zach worked in a little Botcave, had a tremendous number of interesting hoodies, and a deep love for both cats and music that induces physiological experiences.

The Zach’s favorite thing in the whole world was to to print out objects on his 3D printer, without using rafts. But one day, the Zach experienced corner curling for a few of his key parts. “Oh, no!” said the Zach. “I must find a solution.”

He found a solution: he added tiny one-layer disks to the offending corners of his model and ran it through the belly of the klein-bottle skeining monster deep in the heart of the Botcave.

The Zach’s friendly MakerBot 3D printer creature constructed the model again — and this time no curling! ”Look, mouse ears!” the Zach said. He now proceeds to snap the ears off and clean up the corner of his model with a little knife. And if we are very patient, very soon we might see what the Zach will do with his little model….

The End.

Mu-ah-ha-ha!

LightningPhil just uploaded designs to Thingiverse for a Van de Graaff machine.  A Van de Graaff machine is a device for creating an electrostatic charge.  We’ve all seen these devices before – they essentially make your hair stand straight up and create lightning.  While the details and instructions for actually assembling his designs are still sketchy, this is a very exciting development. ¹  As his directions suggest, “A Van de Graaff generator is essentially a box, a tube and a ball with some gubbins that connect it together and move the charge about.  A box, tube and ball are easy. With a 3D printer, so are the gubbins.”  I can’t wait to see his finished product!

As soon as I saw this I had an idea for how to make use of these designs from some parts to which just about every MakerBot operator has access. ²  If you own a Cupcake CNC you can extend the Z axis threaded rods above the level of the Z drive belt.  Most users opt to lower these Z axis threaded rods so that they extend into the lower cavity of the Cupcake, saw off the excess rod, or sometimes leave them extended off the top of the Cupcake and add a Z axis rod topper or Z axis crank.

I would think it very possible to modify your Cupcake to use the top of one or more Z axis rods to act as the drive for a Van de Graaff generator.

3D printing is a lot of fun, but it would be a lot MORE fun with lightning.

1. Seriously, what the heck is a “gubbin??” [↩]
2. Photo courtesy of tobascodagama [↩]

Heart Gears by emmett (Opened in Wings3D)

While MakerBot Operators are more than happy to print the thousands of incredible objects posted to Thingiverse, eventually many catch the design bug and reach out for guidance for how to get started designing models.

Your mission: to create a solid, manifold (“watertight”) STL-formatted file for importing into ReplicatorG. STL, created as the format for stereolithographic CAD files, is a ubiquitous format, so the design application options are vast. ReplicatorG also offers experimental OBJ and Collada file import capability — though the files are then converted into STL files. (You can open dozens of file formats in MeshLab, netfabb Studio Basic or similar 3D swiss army knife tools — and then export as binary or ASCII STL files, opening up even more models to ReplicatorG.)

Choosing Your Hammer

8-bit Heart by schmarty (3DTin.com image)

For design software, there are many powerful free and open source design tools for us to introduce to Operators. Favorites include 3dtin.com, Sketchup, OpenSCAD, Wings3D, and Blender. We have heard about but not experimented much with POV-ray (excellent tutorials here), FreeCAD, HeeksCAD, and Art of Illusion — apps that have serious fans in the 3D printing world.

Plastruder MK5 Solidworks 2011 Model by kai

For commercial solid CAD apps: Rhino (Mac users — jump on the free beta), Autodesk Autocad, Inventor, Creo, and SolidWorks are probably the biggest players in the field. But perhaps you don’t have upwards of $1k to spend on design software? Try the highly-capable $99 Alibre Personal Edition, Cheetah3D (mac only), or bonzai3d.

Below the fold is a handy five step exercise for brand new designers to get their feet wet with 3D modeling.

Read the rest of this entry »