Monthly Archives: July 2012

Seej at Maker Faire Detroit 2012

There are splintered shields and broken hopes among the solder blobs on the ground at the Henry Ford, site of Maker Faire Detroit 2012.

MakerBot Industries was kind enough to give me the opportunity to talk about Seej at their booth on Saturday. Afterwards I hung around and played Seej against passers-by, losing more often than not.

While I was playing I realized that players need a way to commemorate their games. I usually travel with a backpack full of tools, including a Sharpie. So I signed and dated a few bloxen and left them with the booth crew.

Unfortunately there’s not a lot of room to write on most of the current designs. This is remedied with the Tournament Bloxen; it sports a large, flat plaque upon which players can immortalize an event:

Flagrant stagecraft alert: I didn’t have this tournament bloxen at the Maker Faire, but if I had, this is exactly what I’d have written on it before handing it over to a victorious opponent.

I’d like to accumulate a mantel full of these, signed by different Seej players.

The gentleman in the Makerbot t-shirt is Matt Griffin from MakerBot Industries, all-around nice guy and excellent child wrangler, refereeing a match.

The younger kids seemed mostly interested in building structures out of bloxen. MakerBot had printed a few dozen bloxen of various kinds and colors, so there was plenty for them to work with. Look at the size of this stack protecting a young Seejmaester:

This kid destroyed me in about five turns.

Note: if you and/or your child appears in one of these photos and you’d like it removed, please notify me immediately.

Download the Tournament Bloxen from Thingiverse.

All work and no PLA makes Zheng a dull boy

I’m headed off to Maker Faire Detroit in a few hours, and I needed a new Penny Ballista to take on the crew from MakerBot in a no-models-barred Seej match. So I personalized the nock on this one and gave it a go printing with PLA.

The Replicator can print in (at least) two kinds of plastic: ABS, which is the stuff LEGO bricks are made of, and PLA, which is a biodegradable wonder plastic made from corn.

PLA works better than ABS at lower printing temperatures. I’ve been lowering the extruder by 1° every time I print something new, and still haven’t found the floor.

This is my first set of prints with PLA, and I like what I’ve seen so far. I bought this roll from JetJet2004 on Amazon a couple of weeks ago, and I haven’t been disappointed with it yet.

I also printed some Seej Bloxen, Riveted, which aren’t available on Thingiverse: if you want one, you’ll have to solve the
Cryptstone Challenge.

So! Find me walking around with a ballista in my pocket at Maker Faire Detroit on Saturday. I’ll be the pale geek in cargo shorts and a t-shirt.

Benzene, done that.

I’ve always liked the anecdote about Friedrich August Kekulé von Stradonitz and his fevered daydream about the chemical structure of benzene, and apparently I’m not alone.

Regardless of how much truth there is to Kekulé’s story, I try to sneak the word “ouroboros” into conversation as often as possible. It’s a lot easier for me now that I can say, “Hey, check out the ouroboros I designed.”

You can see some rectangular bits of sprue protruding from the base of the model in the photo above; they exist to keep the model from toppling if the extruder tip nicks the top layer of the print. The sprue isn’t in the final model.

I have a dual-extruder replicator. The unused nozzle in this single-color print kept bumping into the right prong of the snake’s body as the extruder traversed the X-axis. This tells me my nozzles are out of calibration by a micron or two.

I solved this problem by rotating the snake 45° around the Z-axis so the prong tips moved out of X alignment, which is a handy cantrip to have in one’s grimoire.

This is a fairly fast print so I was able to go through lots of iterations to get it right:

This model is future-proofed, at least for a while. There’s some detail in the eyes and mouth that is going to have to wait for the next generation of extruder technology to be fully realized. You’ll also note some slight nickeling in the curve of the body, but I designed it to be smoothed easily so we can squeeze another few years out of it.

The tail and mouth are connected by a couple of polygons– this is the one artistic change I really didn’t want to make but I just couldn’t get the model to print reliably when they were separated.

I’ve got the serpent broken out as a separate model, so maybe if I get the time she’ll be transincarnated as cobra.

1.75mm ABS Green
raft
10% infill
Feedrate: 25
Layer Height: .2
HBP Temp: 116°

Funky color combinations

This is my newest favorite color combination: it’s 1.75mm ABS Green Filament scraps under the LED lights from my MakerBot Replicator.

No Photoshop saturation filters: this image is straight out of the camera. The little structure to the left is the base to the Zheng3 Firecracker Cannon.

A nice piece of design on the Replicator that you don’t often see in demos is that the lighting inside the build volume starts blue and gets redder as the machine warms. That was a little piece of magic for me the first time I fired mine up. Well done, Makerbot Industries.

Optimizing hobby time

There’s never enough time to do everything I want to do. Gotta get up and make a new Seej model. Gotta get that IR-sensing followbot built. Gotta hit the gym. Gotta watch another episode of Breaking Bad while I work on cardio. Gotta do the laundry. Gotta learn Brazilian Jiu-Jitsu take six months off to heal a rotator cuff injury from hitting the gym too hard so I don’t get pwned at Brazilian Jiu-Jitsu. Gotta study Chinese.

I read Chinese at sub-kindergarten level, so I’m always looking for opportunities to reinforce my written vocabulary. And since I’m a busy guy, I try to make my hobbies do double duty whenever I can. Here, I’m learning some new words and doing a little 3D printing on the side.


Here are the translations of the characters, so you can make sure everybody at the table gets the correct rest. I’m using traditional characters because they’re prettier. You can download this whole set from Thingiverse for free if you like.

Māmā 媽媽 is pretty universal: that’s mom.
Bàba 爸爸 is dad. From there:

gēge 哥哥: older brother
dìdi 弟弟: younger brother
érzi 兒子: son

jiějie 姐姐: older sister
mèimèi 妹妹: younger sister
nǚ’ér 女兒: daughter

I’ve also included “concubine” and “eunuch” in case anyone in your household fits those descriptions:

qiè 妾: concubine
huànguān 宦官: eunuch

I’m 99% sure that as a non-Chinese American I’ve missed some subtlety in familial relations. Native speakers/Mandarin experts please correct me by email, Twitter, or in the comments below. 谢谢。

Complexity is free.

The spools of ABS that I purchased when I bought my Replicator are finally about to run out, so I went online to get some new ones.

I ended up getting some green ABS and blue PLA from Amazon reseller jet_jet2004, who was nice enough to throw in an extra kg of PLA as a courtesy. Thanks, Jet!

I got the box open and discovered that the spools don’t fit on the back of the Makerbot. The spool bores are way too small. Opportunity!

I opened up the Tinkeriffic Gear Set, did a little vertex slice and dice, and printed a pair of spindles that fit snugly in the holes. Five minutes of Tinkertoying later and I have a functional spool setup for 40mm plastic spools.

Last week I was listening to Science Friday: Can 3D Printers Reshape the World? when Ira Flatow was interviewing Bre Pettis, Hod Lipson, and Terry Wohlers.

Wohlers said something that stuck with me: “With these printers, complexity is free.”

Complexity of design is no longer a barrier to (small scale) manufacturing. The complexity of a design is baked into the process; there’s not much difference from the human perspective between manufacturing baroque and mundane objects.

Press a button, get an object. Let the robot do the work.

There’s no reason for the wavy spokes on the spindle except to adhere to the Rule of Cool. But they exist, and it doesn’t take any more human effort to have them than it would have taken to omit them.

There are many. other. fine. spindles. on Thingiverse, but think this one is the first that’s designed with Tinkertoy compatibility in mind.

Download it here.

It’s Getting Hot in Here

Hot In Herre by Nelly. Love this song.

The East Coast of the U.S. is in the middle of a heat wave, Colorado is on FIRE, and I just finished putting a new heated build platform harness into my MakerBot Replicator.

This is the third HBP harness I’ve been through since I’ve owned the Replicator. This one’s a nice shiny red, which works for me semantically. Red==hot. Nice touch, MakerBot Industries.

Apparently this was a common enough problem that MakerBot redesigned the thing to handle higher temperatures.

HBP Harness numero uno failed a few months ago:

It started with a little charring around the power pin. I asked MakerBot if this was normal, and they said no and shipped me out a new one immediately.

HBP harness #2 lasted a few weeks before the charring started, this time on the ground pin. I didn’t realize how bad it was until I took apart the Replicator and got a look at the underside. Lucky for me I contacted support way, way before it finally failed.

Into the parts bin with you, buddy. I give you 3:1 odds of being resurrected as part of a robotic abomination sometime in the future.

Earlier today my HBP was stuck at 25°C, so I busted out the allen wrenches and the tiny screwdrivers and replaced the meshuggeneh harness with the spiffy new one.

MakerBot Industries tech support has been top-notch with sending out replacement parts. Thanks guys and gals, I’m back in bidness.

New design up on Thingiverse tomorrow. (7/4/12, you read it here first.)