Rotary Sprinklers by Supermange

If you’re using Google Sketchup for designing 3D printable models, you may have noticed that exporting to STL’s using some of the various plugins can be very hit-or-miss.  After checking out Supermange’s rotary sprinklers I was reminded of this quick fix for a very common design problem in Google Sketchup – the “flipped face.”

Looking at the screenshot above, you’ll notice that the facets of the object are either a white-and-light-gray tone or a dark-gray-and-darker-gray tone.  As a surface modeler, Google Sketchup doesn’t much pay much attention to whether a surface is on the outside or inside of a model.  However, once you turn it into an STL, this can create problems.

Fortunately, this is an easy problem to fix.  All you need to do is right click on the darker face (such as much of the top right flange of the model above) and select “Reverse face” from the menu.  While you can select multiple faces at once and flip all of them simultaneously, this still leaves a minor, and somewhat tedious, problem of detecting the flipped faces in the first place.  If they are too numerous or tiny to locate, you might be better off using some STL correction software to fix the flipped faces.

SketchUp to STL Plugin with No Dialogs by br3ttb

Google Sketchup is a free surface modeling program with a gentle learning curve.  While it does not export to STL’s for 3D printing, users have created some plugins that give it this functionality.  Thingiverse user br3ttb has made this process even simpler.  After installing his hacked version of an existing plugin, an STL of your work is just a few clicks away!

As a bonus, I’ve been collecting some of my favorite Sketchup plugins.  You might find some interesting ones in that list.

I sometimes have trouble getting a watertight STL out of Sketchup.  What software do you use to fix meshes?

Thanks for the tip Chris!

Castle MakerBot by Renosis

Thingiverse citizen Carmiac recently put together a “Bot Bling challenge.”  The winner was to receive $35.00 from Carmiac himself and MakerBot kicking in some LED’s!  The challenge recently concluded with the winner, Renosis for his “Castle MakerBot.”  From Carmiac:

Congratulations to Thingiverse user Renosis for winning the BotBling Challenge!  His Castle MakerBot entry has everything, great design, complete files, options galore, and over the top awesomeness.  The only thing missing is a moat!

Big thanks and kudos to all the entrants, and stay tuned for my next challenge!

Renosis’ “Castle MakerBot” entry includes:

• Four turrets
• Coat of arms, with 7 different logos in three different positions
  • MakerBot logo
  • Thing-O-Matic
  • Cupcake
  • Unicorn
  • RepRap
  • RepRap logo
  • Open Source Hardware logo
• Medieval torches
• Stained glass window
• Gen4 Interfacenumeric keypad firmware hack
• Runic keypad labels

He even included all the source files for his work.  These included a PDF of the keypad labels, DXF files for some of the logos, Sketchup files for stained glass window, and OpenSCAD files for everything else.  If you’ve ever needed to turn a MakerBot into a castle, this is hands down the only way to go.

I wanted to make sure our 8 month old son felt welcome in our new home, and what better way than by putting his name on the door of his room in Makerbotted letters!

I looked on Thingiverse, where there are more than a few sets of letters for blocks and for including in OpenSCAD, but it turns out that it is super-easy to make 3D extruded letters in Sketchup.

1. Download and install Google Sketchup, if you haven’t already.
2. Make sure you have an STL export plugin installed. I use this one but there are others.
3. Start Sketchup
4. Go to the Tools menu and select 3D text
5. Type your text (it can be a single letter)
6. For your dimensions, 0.075m for height will fit nicely in a Makerbot. 0.01 extrusion is good to start with.
7. Press the Place button
8. Select your letter, and find the STL export option. If you used the plugin I linked to, it’s in the Tools menu.
9. Select millimeters as your export unit
10. Select STL as your export format
11. Open the STL in ReplicatorG
12. Use the Move button, and then Center + Put On Platform to get it all lined up
13. Print!

Hydrant Totem by tbuser

Yesterday morning, moments after learning about the Tinkercad beta, MakerBot Operator TBuser dived in head first to test what he might do with the tool. Before necessarily arriving at any specific sense of what his model might be, he sent me the model (simply by passing me a Tinkercad link).

Five minutes later, my bot was printed his object first at 1:1 and then at 2:1 scale without any cleanup or manipulation of the model other than centering it on the build platform. The MakerBot Thing-O-Matic on my desk (with a Stepstruder MK6 and 0.4mm nozzle) had no difficulty printing the model despite a number of challenges (like the cylinder cut through the middle) at either scale — and I was able to hand over the models to Tony before he had had much time to notice that I was printing it out.

Take a look at Tony’s Thingiverse release of the item (now a “Hydrant Totem”) and consider the implications of this workflow model. Not only is he able to generate a printable STL with a one-button click (which can be easily revised and adjusted in a host of STL scripts and tools) but he can also share a link to the model in Tinkercad so that another user might duplicate the project, make revisions, and then print a new model.

This is game changing, folks. Imagine how much easier this route is than jumping through hoops to share SketchUp files.¹ Share a Tinkercad link and others can work on your model in its original design environment right in your browser.

TinkerCAD is still in beta, so I suggest you jump in to push this tool hard as well — and send constructive feedback to the developer. This tool is shaping into something I have been waiting for since exploring the charming 3dtin.com.

Untitled by tbuser

This thing brought to you by

1. The past benefit of Sketchup being the wide adoption and lower learning curve for modeling. [↩]

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 »

Scale up!

Srsguy brings us a quick design hack for Google Sketchup along with his Aerodynamic ramp – EC Fan Mount.¹

**NOTE** Because google sketchup isn’t good with very tiny dimensions, I had to scale this thing up by 1000x in order for it to save properly. Sad, I know HOTFIX: When you’re editing it in ReplicatorG, use the Scale tool and enter the value : .001

Google Sketchup is really really bad when you get to millimeter scale objects. ²³ At that scale it starts to delete random faces and won’t let you draw faces with an area less than 1 mm square.  So, just start working with meters instead, drop the scale in ReplicatorG and rock on!⁴⁵

Sketchup isn’t open source, but it is free.  While it would be great for newer features to also be free in order to help democratize production, it is still super easy to use.  With some of the great plugins for Sketchup and his handy dandy hack, we should be able to make anything!

Thanks Srsguy!!!

Scale down...

1. Photos courtesy of Ninnoz [↩]
2. They’re like all, “We’re google, we like big numbers.  We don’t have tiiiiiiime for small numbers!” [↩]
3. Which is funny, since they’re always refactoring their search algorithms for small response times… [↩]
4. For my fellow nerds out there, you are decimating the scale three times…  UPDATE:  Patrick VERY correctly notes that I got this totally totally wrong.  I mixed up reducing BY 1/10 with reducing to 1/10.  The math is strong with this one. [↩]
5. Do you remember that bit in Doctor Who The Sound of Drums when The Master had his little spherical minions attack the populace?  He said “Decimate them!” or some such and then followed it with “Remove one-tenth of the population!”  I was so proud to be a Doctor Who fan that day… [↩]

Analog eggs are so fragile

Because they’re difficult to put back together again. ¹  Taking a digital object and converting into an STL will essentially shatter it into a bunch of triangles.  This is great if you’re a 3D printer.  It’s not so great if you want to open, edit, modify, scale, create a derivative, or do anything with that digital file other than just print it.

Not infrequently people will upload their designs to Thingiverse just as an STL file.  This is great for printing, but not so great for creating derivatives.  Other times, people will upload their design files, but not an STL.  This is great for creating derivatives, but deprives users of being able to preview a thing and hampers them if they don’t have a program that supports the file format.

I’m a big fan of Google’s Sketchup.  I know it’s not open source – but it is free and super easy to use.  There are several STL import plugins for Sketchup that all work with varying degrees of success.  They tend to miss the finer details on objects.  The only reliable way I’ve found to edit an STL file without a loss of data is to import it into Blender, save as a 3DS file, and import it into Sketchup.

One problem with editing an STL file even after it has been converted into a more fungible format is that what was once a simple structure is now a spider web of triangles.  Editing a mess of small triangles in Sketchup could get unwieldy pretty quickly.  In order to simplify the entire model and potentially reduce the number of triangles involved, consider using the decimate function in Blender or the Polyreduce plugin for Google Sketchup.  Either method will provide you with a much simpler digital model for editing and modification.

1. Photo courtesy of WaveCult [↩]