Pick me! Pick me!

Okay, I’ve gotten the clearance from Pattywac to join in the United We Stand team design challenge.  Although I voluntarily take myself out of the running from every challenge, I love participating.  They’re just too much damn fun.  :)

I never participate in the judging on these things – but it would look a little odd to have me be both someone who blogs about something and a guy who is the subject of the blog post.  Blogging here at MakerBlock.com, I happily post about anything that comes to mind, even if it is ridiculously self-indulgent.  However, I really don’t want the posts at MakerBot to be about me – I want them to be about the awesome stuff people are doing in the DIY 3D printing community.

The potentially ethical problem I faced with this most recent challenge is that as a team design challenge, I wouldn’t want to disqualify an entire team of people just because I was on it. 1  So, my proposal to MakerBot and Pattywac was that as part of any team, I would agree to forgo any winnings of any kind. 2  This was acceptable to both.

So, are you interested in collaborating on this design challenge?  I’d be especially interested in getting collaborative help on any of my existing projects, going from my highest interest3 to lower interest4 :

  1. Clockwork spider5
  2. Open source disc shooter
  3. A printable clock that actually keeps time
  4. A sonic screwdriver
  5. A dalek that can rotate it’s head, roll, and move it’s gun, eyestalk, and plunger6
  6. A better Voltron
  7. A puzzle box
  1. And, really, having me on your team is hindrance enough. []
  2. I just want to feel included! []
  3. #1 []
  4. #7 []
  5. I’ve already had input and help from Dna on this []
  6. Mad props to innovationbylayers for the existing dalek on Thingiverse []


With my MK6 disassembled1 and work projects stacking up, I tend to become more prolific in writing and designing. 2

Whenever my ‘bot is in need of repair, my mind goes back to all of the projects and things I keep meaning to print…  but never find the time for.  I also think back to design problems I was having… and sometimes come up with solutions!

Take, for instance, the puzzle box from The Mummy.  I’ve been meaning to get back to this for more than six months.  Well, an idea for a way to make it spring open just occurred to me.  I could put another octagon shaped box inside of the puzzle box and a flatish spring underneath it, squished between the two boxes.  If the top of the box is released, the spring would force the inner box up – and against the lid components and the entire lid open.  It would also potentially work well with little spring loaded pins just under each of the lid pieces.  I’m thinking something like a piece of filament forced upwards by the spring from a retractable ball point pen.  Or, if your spring was good enough, the spring could be under just one of the lid pieces – with the other lid pieces laying on top of it.  As that one pieces is forced up, it could force the others out.

Without the benefit of my printer running, I’m also putting a few extra brain cells3 on my clockwork spider project.  I was inspired by several things recently.  First is the video of how a mechanical clock works I had posted earlier.  As you’ll recall from Skimbal’s Rubber Band Gear Mechanism/Engine, a wound spring engine will want to expend all of its energy all at once.

That video describing the inner workings of a clock demonstrates a little regular that only lets it unwind a little bit at a time, so it can expend its energy over a longer time period.  Secondly was Erik’s pick-n-place tape feeder.  This design uses an interesting spring/gear/ratchet wheel.  Skip to 1:25 for a demonstration of the mechanism in question.

Now, in the instance of Erik’s device, it is the ratchet that moves back and forth – rather than the wheel turning at a constant rate.  However, this gave me an idea.  It should be feasible to create a similar spring/ratchet combination to prevent a wound device from expelling it’s energy at once.  Last, but by no means least, is Dna’s rubber band ratchet engine designed to power a clockwork spider.

In pondering my attempt at an open source disc launcher, I’ve been trying to think of the best way to pull back the spring.  If the firing pin/slider is going to be powered by a rubber band, it’s going to need to be a decently sturdy mechanism.  I keep thinking back to a rack and pinion set up.  There could be a notch in the bottom of the firing pin/slider, a peg in the flat side of a rack, and a small gear run off of a big gear, with the trigger on the big gear.

What else?  Um, I think the tank by mraiser could make a good platform for a larger clockwork spider.  Also, I would like to see a version of the tank that’s run off of clockwork/gears/regulators/rubber band/springs.

  1. More on this later []
  2. I didn’t say better, mind. []
  3. Both of them! []

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.

And you thought *I* was wordy…

My wife started a blog about knitting.  :)

If you showed up for Botacon, you actually got to see some of our work during my presentation.  She’s designed some napkin holders and knited bangles. 1

  1. I designed and printed the PLA inserts. []
March 17, 2011 | Comments Closed

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 []
March 14, 2011 | Comments Closed

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.”

March 12, 2011 | Comments Closed

SpiderBot – once more into the breach!

So, I’m about to begin a completely new design on my little spider bot using what I’ve learned from the last try.

Failure is fun!

March 6, 2011 | Comments Closed

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.