Category: Tips

Tips learned from experience building a MakerBot

Can we make a printed Nerf dart shooter?

I’m curious.

I figure a typical Nerf dart shooter works as so:

  1. A dart with a plastic cap and a hollow center
  2. Putting the dart in a thin cylinder, with the cap facing out
  3. Pulling back a larger cylinder that fits around the thin cylinder, where the larger cylinder is capped at one end
  4. Suddenly releasing the larger cylinder, so that it will be propelled forward
  5. The air between the two cylinders is compressed, and forced into the cavity inside the dart
  6. The compressed air forces the dart out of the thin cylinder

I think this is doable with 3D printed parts and a rubber band.

Don’t think I’ve given up…

Just because I didn’t label the Clockwork Spider on Thingiverse as a “work in progress,” don’t think I’ve given up on it.  It exists now as an actual physically printed object and I’m very happy about that.  However, the legs are just a stand-in1 for nice spidery looking legs I’ve already designed.  There’s no point in printing the real legs up until I’ve gotten a mechanism that will make them work.

  1. As it were [↩]

Clockwork spiders

I’m so freaking happy with the design, print, and assembly.

You can assemble the entire thing by hand in just a minute or two with no tools or hardware.  Turn the center wheel to make it walk.  Right now the gears are a little rough – but I have an idea on how to fix that in the next revision.  But, if the gears turned even slightly better, I think this design is almost ready for the big time.

I cannot wait to have a printed wind up rubber band powered clockwork spider skittering across my desk at work.

*skritch* *skritch* *skritch*  “Oh, don’t mind leggy.  She can smell fear.”

Spiders + Robots = two great tastes that taste great together

I just uploaded my latest designs to Thingiverse.  I’m working on a RoboSpider using a set of gears run in an elliptical cycle.  I’ve been through a few revisions already and just came up with a new idea on how to design it with a thinner profile and hopefully work more reliably.

Unfortunately, the snap-together system I had designed just wasn’t working very well.  Also, my very VERY DIY gears are a poor substitute for using a legit gear script.  They don’t mesh that well and it shows.  I think I’ll give Cbiffle’s spur gear script filter for Greg Frost’s gear script a shot.

In the meantime, is anyone interested in designing a little rubber band powered motor to drive this thing?

MakerBlock Thing-A-Day

Let’s see if I can upload a new thing to Thingiverse for each day in February.  This post will be my updated list of Things as I upload them.

With great power

Comes abuse.  I’ve come to realize that OpenSCAD can indeed be abused.  It’s so easy to import several objects and manipulate them that I wish I had gotten around to learning OpenSCAD a long time ago.  You can do some pretty amazing (and scary) things with just the import and translate functions. 1

And, in retrospect, I probably could have whipped up that Voltron remix in a fraction of the time if I had OpenSCAD at my disposal…

Oh well, that just means the next time I’ll be that much better.

  1. I also scaled Disney’s head to an appropriate size, but it wasn’t compiled by OpenSCAD [↩]

OpenSCAD tutorial outline

They’ll continue, but I think the next one will come out on Friday.  So far I’ve covered the interface of OpenSCAD, 2D forms, and 3D forms.

My goal is to show people how to use OpenSCAD in a way that is intuitive and builds quickly on what was taught earlier, with a secondary goal of getting the reader to be able to make something useful as quickly as possible.  Here’s the rough outline/idea of where I’m going:

  1. OpenSCAD interface
  2. 2D forms
  3. 3D forms
  4. Union/difference/intersection
  5. Rotate/mirror/translate/scale
  6. Variables/module
  7. Linear and rotational extrusion
  8. Using other programs to make using OpenSCAD easier (Sketchup, Inkscape, Notepad++)
  9. Include/libraries
  10. Conditional and Iterator Functions

I know I’m leaving a lot out of that outline.  What would you like to see?