Monthly Archives: August 2012

Seej Pillar

My Seej fortifications have been looking a little mundane lately so I designed this seven-piece fluted column to add a little bit of architectural elegance to my battles. It handily interlocks with existing Seej bloxen, and collapses spectacularly when hit with a penny from a Seej engine.

It’s pictured here with a Riveted Bloxen for scale.

This post was originally going to be about how to adjust your gCode by hand-tweaking it to get a good raftless PLA print, but then I went ahead and downloaded ReplicatorG 037. Editing gCode wasn’t necessary, except to set the HBP temperature to 65°.

Perfect print the first time out, even with a relatively complicated model like this one. No hocus-pocus required.

1.75mm Blue PLA (available at Amazon)
Infill 10%
Layer Height .20mm
Shells: 1
Feedrate 25mm/s
Travel Feedrate 55mm/s
Print Temperature 190°
HBP Temperature: 65°

Download it here.

Blazing fail.

This is a failure of a Seej Masonry Bloxen.

I stuck an LED inside it to highlight the software-generated infill pattern.

ReplicatorG does this cool thing when preparing the model for printing, generating a honeycomb pattern for large solid volumes. Presumably this feature was designed to save plastic and printing time.

It’s like magic the first time you see it in action.

This is a PLA print at 10% infill. One hundred percent infill would print a solid block of plastic.

Chinese is puzzling.

My Chinese teacher is on vacation this month, so while my spoken proficiency withers on the vine I thought I’d brush up on my geography. Laoshi is visiting Xinjiang, which as I understand it is like going to Wyoming but with spicier food and fewer AK-47’s.

I don’t expect this to be one of my more popular models; the last time I tried combining my hobbies I wound up with the Happy Family Chopstick Rest Set, which is bumping along the bottom of the lake with 23 downloads as of today.

Seej models are much preferred by Thingiversians. The Seej Starter Set is at 431 and the Penny Ballista is well over 1200 (!) downloads by now.

A 3D map of China is a pretty nichey thing, but the design and printing process has been a really valuable educational experience for me, so time well spent.

The first approach to this model was the straightforward one– find a public domain SVG China Map, download, and extrude.

Any map you find online is going to be a crapshoot– either too much data, not enough data, or poorly organized data. My rule of thumb is if I can’t find what I need in seven minutes, it’s probably a better use of my time to just put in the work and do it myself.

So, to Illustrator it is, remaking each province control point by control point with the pen tool, letting the names and forms seep into my subconscious.

At this point, about six hours in, I can feel the names and shapes starting to gel. Mnemonics arrive unbidden: Gansu is kind of long-necked like a goose, and ganso is goose in Spanish, so there’s a connection there. Heilongjiang resembles Bill Peet’s Droofus the Dragon looking out of his cave — Heilong literally means Black Dragon in Chinese so I’ve got that one down.

Whoops, missed the border between Jiangsu Jiangxi and Fujian. Easy fix. Jiangsu and Fujian don’t share a border. Remember that for later. And the border between Hebei and Shaanxi (or is it Shanxi? Crap, it’s Shanxi) isn’t going to work when it’s printed in 3D. Tweak, tweak, tweak, learn. Part of Xizang’s south is disputed by India. Ok, two models for Xizang. We can probably ignore the disputed western border and chalk it up to the puzzle’s resolution.

It should be easy enough to remember there are four municipalities– Beijing, Shanghai, Tianjin and the sprawling megacity of Chongqing. The first three are too small to print, so I’ll just have to remember that they exist.

The islands. Hainan, Macao, and Hong Kong are easy to remember, although the latter two are too small to include at any reasonable printing scale. Which brings me to Taiwan.

Is Taiwan part of China? That really depends on who you ask. If you ask the People’s Republic, they’ll tell you absolutely, Taiwan’s a part of China and it always has been. If you ask the Taiwanese, you’ll get a hell no.

The United States is emphatically wishy-washy on the matter. Our official position is that we’d like Taiwan’s relationship to remain the status quo, without ever defining what the status quo actually is. This is why we invented diplomats, I suppose.

Taiwan’s in the model and users can choose for themselves whether or not to print it. I think it’s better to include it with the caveat that its diplomatic status is in dispute: that’s a much more interesting and instructive answer than yes or no.

Printing tip: ABS seemed to shrink too much post-print to ensure a good fit between pieces. I printed a second version in PLA, which is a lot more malleable.

I put the whole map (minus the islands) on a cast-iron griddle, heated it up, and then gently pressed the pieces together. Now every province is nice and snug with its neighbors.

I’d have used a wok, but I didn’t want a concave map. This time.

You can Download the .zip of this puzzle for free from Thingiverse. Includes PDF maps in English, pinyin, and Simplified characters for your educational convenience.

Replicator Maintenance

This morning my Replicator wouldn’t accept a new filament. I’d get the filament a few centimeters into the extruder and then it’d just stop moving and start clicking rhythmically.

MakerBot tech support (great tech support, by the way) suggested I follow their maintenance video and clean out the extruder.

Here’s the culprit. Earlier I’d clipped a filament without doing a proper unload procedure and it got stuck. Don’t do this.

Naturally, it broke off when I heated the extruder and tried to pull it out, so there was nothing to do but force it through with one of the many poking tools around the Replicator’s eyrie.

As long as I had the thing taken apart I cleaned the crufty buildup of filament particles off the stepper.


And now I’m back in business with some red ABS. New model coming soon.