Monthly Archives: August 2013

Scarab Queens Battle Flag

Battle Flag, Scarab Queens

“A chambermaid found the first grub, and we knew the battle was already lost.”
–Qie Zi, The Art of Seej

In 2012 the Scarab Queens announced themselves to the world of Seej with the publication of the Hexstone Bloxen, but didn’t get around to hoisting their battle flag until just recently.

download

The Scarab Queens infest the works of Men, slathering the Pennon with comb and royal jelly. This model is a one-piece print on an FDM printer. I had decent results printing at .18 layer height with ABS, but I’ve done test prints with PLA too that worked out fine.

The Scarab Queens rule variant allows a player to add one projectile to his stockpile for every three hexstone bloxen in his fortification, provided he also fields a Scarab Queens battle flag.

This model and many like it are available for download in The Forge.

Plunger Fail

Lately there’s been a proliferation of 3d printing failure blog posts percolating around the twitterverse. I’ve got plenty of these on the blog already, so I’m dropping another one in the spirit of mutual commiseration.

Plunger Fail

I’ve been printing dozens of bloxen in preparation for Maker Faire NYC lately, and finally managed to wear out one of my delrin plungers. I had two or three days of intermittently failing prints before I figured out the problem.

I printed a new one, but printing a replacement plunger while using a faulty plunger leads to interesting results.

Ultimately I held my filament in place manually while the replacement plunger printed. It’s a quick print, about five minutes, so it was a good time to put a little dent in my Netflix queue.

Quality Control

I recently released a Magic: The Gathering Snake Token into the wild, but many iterations of the model got left on the scrap heap before the final slithered off the build platform.

Here’s one that made it all the way to the light tent before I realized the many problems it had. Sometimes you don’t see all the problems until you really dig into a macro photograph.

Snake QC fail

  • overhang: violations of the 45° rule. Not terrible on this one.
  • scrubbing: the model’s too thin here. ABS or a cooling fan might help.
  • nickeling: not enough geometry to make a smooth curve in the body
  • schmutz: really should have filed this off before painting.
  • I can forgive a little bit of overhang on a model. Sooner or later some 3d printer manufacturer’s going to lick that problem for us. Scrubbing is a technical issue too, and schmutz removal is a time-honored pre-photography process that I was just too lazy or preoccupied to do on this model.

    It is the nickeling that I shan’t abide.

    I come to 3D modelling from a video games background, where realtime constraints force model efficiency. When I was a lad with an onion tied to my belt, which was the style at the time, we designed characters with 150 triangles and we liked it that way.

    So every now and then I forget that I’m not living in 1997 anymore and I can be a little more luxurious with the poly count. It still feels dirty though.

    So Ms. Cobra went back into the Forge, got subdivided again, re-posed, edited, tweaked, and was reborn as the final product you saw a day or two ago.

MTG Zombie Token

MTG Zombie Token

downloadWhen looms a medieval zombie apocalypse (which, frankly, happens every time the local necromancer goes for a stroll) it’s not the lords and ladies, safely ensconced behind thick citadel walls and rows of nervous archers who get chomped; if serf’s up for Jack and Jill mudgrubber they’re crudités for Zed anon.

With a model this small, it’s all about pose. How do you communicate shambling corpse with the broadest strokes, while keeping overhangs to a minimum?

Some details unfortunately get lost in the printing, like this lovely compound tibial fracture.

I’m a little disappointed in the resolution of the print. Even at .1mm layer height the finer details of Zed’s leg get lost, as does his partially-revealed skull. My understanding is that several key powder printing patents expire in 2014, so perhaps by then we’ll be able to print this zombie with all his putrid details intact.

At that point I’ll have to go back and add some facial features, because for now Zed doesn’t have a nose or clearly defined mouth.

ComposiMold: First Impressions

The friendly team at ComposiMold recently sent me a sample of their product for review. Like many experimenters I’m mostly unacquainted with mold-making and casting but I’m willing to get messy and give it a go. Let’s dive right in and see how this stuff works.

TL;DR Summary: ComposiMold is easy to use, reuse, and reuse again, even for a casting n00b. It’d make a great gift for a Maker kid. Highly recommended.

Composimold: The Unboxening

open container

Opening the 10-ounce container releases the faintest waft of lemon. It’s not unpleasant or pronounced; only bloodhounds and those accustomed to huffing day-old mimeographs will have the chemoreceptors to detect the scent.

It’s firmer than I expected. I was thinking I’d have something a little gooier, but when ComposiMold is cool it’s got the consistency of a flexed bicep. At 10 ounces the sample container feels satisfyingly dense in the hand. I feel like I could make stuff with this.

Virgin ComposiMold looks surprisingly like honey. So much so that the lovely and talented Mrs. Zheng3, slightly less talented than usual at 5:30am, nearly dropped a heaping spoonful of ComposiMold into her oatmeal. I probably shouldn’t have left the container on top of the microwave last night.

In theory, the mold making process is simple and straightforward: heat ComposiMold, pour it over the object you want to reproduce, allow to cool, and then extract your object.

Naturally I screwed it up.

Jumping into this project like an enthusiastic idiot I naturally made a a rookie mistake right off the bat. I forgot to coat my mold container with a release agent. So I restarted the project. What you’re seeing here is actually take two on my quest to replicate a Seej bloxen.

So! Into the microwave with you, ComposiMold.

in the microwave

Another brief installment of Zheng’s household hints: before photographing the inside of a microwave you’ll want to clean it so the Internet doesn’t think you’re a gavone. Put a cup full of vinegar in the microwave and nuke the bejeezus out of it. The steam will soften the Hot Pockets splatter off the inside of your microwave so that you can wipe it clean with a rag. The healing brush in Photoshop will take care of any pastacules you might have missed.

Thirty seconds in my microwave and I’ve got a golfball-sized nugget of ComposiMold suspended in honey-like goo. Stir with a craft stick (always, always, always have craft sticks around any maker project), give it another 20 seconds of non-ionizing radiation and we’re good to go. During the melt the lemony scent is a little more pronounced but doesn’t stink up the kitchen.

bloxen, masonry
I’ve decided to try and cast a Seej Bloxen for my first project. I’ve made sidewalk chalk bloxen using a 3d printed mold, but I’m interested to see how ComposiMold picks up the detail in the 3D modeled grout and stones of something I’ve already printed. This particular bloxen was produced during my review of Filabot’s recycled ABS filament.

Composimold: Making A Mold

I give the bloxen a rub with some vegetable oil and put it into an old laundry scoop. Here’s where I run into my first unknown unknown in the mold-making process.

pouring

unforeseen problemThe plastic object I’m trying to copy is less dense than ComposiMold, so it wants to float. I try holding it down with a craft stick, but I’m unwilling to wait half an hour for the ComposiMold to solidify at room temperature. I throw the whole thing in the freezer to cool and abort the first try at mold-making.

It’s 9AM on a Sunday morning so I take a break and have some cheese danish before the kids get up and eat it all. After twenty minutes and a cuppa joe I cut open the mold to see how well it captured the details. Click to embiggen.

detail

The detail’s quite fine here. ComposiMold even picked up the layer artifacts left by the 3d printing process. Each of those parallel lines is about 100 microns wide. I can’t use this failed mold for casting, but it provides an excellent chance to test ComposiMold’s reusability.

Forty-five seconds in the microwave and I’m back to pouring a new mold. Easy peasy George and Weezy. So far ComposiMold is living up to its promises.

This time I’ll try suspending the bloxen from a stiff piece of hookup wire before I pour. I drill a small hole in the side of the bloxen, superglue in a wire scrap, and wrap it around a craft stick. (See previous admonition about having craft sticks around.) I’ll use a plastic cup for my mold container this time, because I can just cut it away without having to worry about pre-treating it with mold release. The vegetable oil gets everywhere and I don’t want it schmeered all over my camera and light box.

suspended

The bloxen remains submerged this time, if a little off-kilter as the unsecured bottom of the plastic tries to float upwards. The newly-poured mold goes back to the freezer for fifteen minutes or so before I cut away the plastic cup.

The mold resists my hobby knife with the strength of an overcooked ham, but splits easily and the bloxen pops right out. A little vegetable oil on the inside of the mold and it’s ready to be filled with Plaster of Paris.

ready

Composimold: Casting

ComposiMold’s produced a perfectly usable mold. The process has been simple even for a mold-making novice, but today I’m wishing I paid more attention on casting day in sculpture class.

In all fairness, I was trying to get the lovely and talented not-yet-Mrs. Zheng3 to notice me at the time.

plaster

Notice that almost all the bubble artifacts on this plaster bloxen faces inwards; this isn’t ComposiMold’s fault, it’s mine. Either I didn’t get the plaster/water ratio correct or I didn’t agitate the mold enough after pouring, or my plaster’s old, or something else. I’d love to see what ComposiMold can do in the hands of someone with more casting experience. ComposiMold also sells a bubble buster that will assist in the casting process that wasn’t included in my review sample.

A couple hours of playing with this product has given me all kinds of great ideas for where to go next with this. Traditional casting and 3D-printing are a powerful combination, so #staytuned for another casting attempt, this time with cement. The younger Zhengspawn and I have a project in mind that’s perfect for ComposiMold. We’ll see how an 8-year old does with this stuff under lax supervision.

If you’d like me to put your Maker-related gizmo, material, tool, or software through its paces at Zheng3.com, email me and I’ll give it a shot.

Capture The Flag IRL with 3d Printing

capture the flag set

In the Early Days, before there was Team Fortress, and before there was Quake, and before even Doom or Wolfenstein were ideas, in the Early Days when baudrate was a term yet unheard and then forgotten when 56K became the norm, in those Early days did we play Capture the Flag outside, with our very bodies, and in those Early Days we skinned our knees and laughed and played and lost and played ’til the shiny fireflies bid us return home to suckle from the hose of gardens and collapse into mud-streaked sleep.

Zerg rushes of anonymous children punctuate summertime in Barrio de Zheng. They overrun the defenses, screen door swinging, slamming, swinging again. One on the Ouya, two on the xBox, three on the Wii, most doing end runs around their parents’ summertime video game restrictions and conveniently not informing me of the fact.

But enough of pixels and vectors and voxels, little ones. I shall teach you the Old Ways, swaddled in furs sufficiently nerdy to invest you mentally in the game before you become physically addicted to the running and laughing with others of your ilk, for the creaking of my joints is the harbinger of wisdom, and I know how to manipulate younglings as I was once manipulated.

Go, now, and play, before Summer wanes and study begins anew, for the Early Days that belong to you will not last ever long.


download I’m assuming that all 1/2″ PVC is cut from the same thicket off the coast of South Carolina, but you may need to scale the diameter of your rings by some constant factor. I used a 4-foot length of PVC.

I noticed some variance in the internal diameter of my PVC, so I designed the finial and butt spike with some wiggle room. You’ll be filling that space with adhesive anyway.

The rings should be snug but I recommend adding a drop or two of glue to hold them in place once you have them in position.

The butt spike is fairly dull and is designed so that the flag can be snatched from the ground by a running 7-year-old. Don’t plant the flag too deeply in the ground.

capture the flag set

Those who come to CTF IRL with only gamer experience to guide them may be shocked to learn there’s little killing involved. In fact, it’s completely optional, and even discouraged in most venues.

Setup:

Step 1: Choose sides by whatever means work for your particular rabble of kids. Try to divide teams evenly. Smaller children are valuable as sentries, jailors, and sacrificial lambs during a bum rush.

Step 2: Determine the boundaries of play. A yard, a block, a park, whatever you’ve got. In theory you could play this game in a pool.

Step 3: Divide the play area roughly in half. The midline of play needs to be clearly understood by all players, for reasons that will be clear later. Plant your team’s flag somewhere in your territory, preferably as far from the midline as possible.

Step 4: Designate an area within your territory to serve as a jail for captured opposing players. Note the flag guards and jailors hanging back in the setup diagram below.

capture the flag set

Gameplay:

The object of the game is to steal the opposing team’s flag and carry it across the midline. Assume two teams, Red and Blue. The same rules apply to both teams, so you can swap Red and Blue as appropriate from here on out.

At the start of the game, Red and Blue line up in their territory, along the midline. Taunting is encouraged.

A player is safe from capture in his own territory but can be captured with a tag (or tackle, depending on your injury threshold) when in the opponent’s territory.

If Red crosses the midline and is tagged by Blue, Red must immediately go to Blue’s jail and wait until freed with a tag from another free Red player. A Red player can only free one Red at a time from jail.

Newly liberated Red and his liberator get immunity from Blue while walking back to Red territory, and cannot touch Blue’s flag or free other Reds until they have crossed the midline twice and returned to Blue turf.

If Red is able to snatch the flag and carry it across midline, Red wins. No throwing or handing off the flag to another player. A captured flag runner drops the flag where he is tagged.

Some illustrations:

Here, a Blue has crossed the midline and grabbed the Red flag, and is speeding towards the midline pursued by a mob of Reds. One Red and one Blue have been captured in each jail. The Red jailor has left her post to pursue the flag.

capture the flag set

But Blue doesn’t make it back to the midline! Tagged by a Red he must go to jail. Note that a sneaky blue has worked his way around behind the Red jail.

captured!

Sneaky blue frees the captured player! Captured Blue walks back across the midline and may now cross back into red territory to make another attempt on the flag, or free his remaining teammate.

freed!

The player that freed him has immunity, but cannot free the other jailed blue player or attack the flag until he goes back into his own territory and steps across the midline again.