Listen up geeks: you do not want to miss what's goin' down in the labs this Spring. We have new classes and old classics seeking open minds and able hands to help us hack and hot wire our way out of winter. Behold-It's Springtime in the FabLab!

MARCH
13: Intro to the Laser Cutter 10am-1pm $65
18&25: Electronics for Artists 7-10pm $100(includes parts)
20&27: Lasercut a Pinhole Camera 1-4pm $55

APRIL
3: Intro to the Laser Cutter 10am-1pm $65
22: Programming Workshop 7-10pm FREE

MAY
1: Intro to the Laser Cutter 10am-1pm $65
5,9&12: Laser Cut Japanese Woodblock Printing $125
6,13,20&27: Introductory Arduino 7-9pm $200 (includes parts)

Sounds like fun, don't it! Visit our online store for detailed class descriptions and to reserve your spot!
Questions? Comments? Suggestions for super slick hacker savy classes?
e-mail krystal@as220.org

Everything I've posted here is hereby licensed CC-NC-SA, unless otherwise specified (or, y'know, if it's a derivative work.)

The Fuxamascanner is still in progress, so I did a quick (20 minutes) scan of a drill bit in Dr. Picza just for the lulz.

halfdrill-blender.stl

screen /dev/ttyS0 Hitting c seems to clear things, o goes to origin, and s begins scanning. No useful output yet, portmon on Windows proved essentially useless, but I have a full log of a picza scanning session in Windows as well.

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Using bazaar with the fab academy repository
This tutorial doesn't have the server setup part like the previous one did, and goes a bit more into managing files.

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I am still working on my Fab Academy 3D Molding and Casting project (a 3D model and cast of the TARDIS. The implementation of my model proved complicated.

Starting with the cad.py created .rml files (for details on the 3D modeling process see my TARDIS: 3D Modeling post), I carved several molds out a block of machinable wax using the Modela milling machine.

Wax Molds

There were a few mishaps creating these molds. The z-max setting was not high enough on the side mold (you can see where the Modela bit drug through the wax and made lines that were not part of the design.). I learned that it pays to set the z-max close to the max of 1 so that it will clear the edges of the design. However, because this particular design took so long to mill out , 7 hours or so, I opted not to redo it if the damage was minor. Instead, I attempted to repair the damaged areas with wax.

After I made the wax molds, I made casts of each side and the roof using urethane rubber. The door was cast once, but the side needed to be cast 3 times to create the 3D object.

I did not allow for space at the top of the wax molds, so to ensure that the rubber would have enough room to capture the top of the design, I laser-cut some tempered masonite frames in to increase the vertical space for the rubber to fill. These frames also make it a little easier to get the rubber out of the mold. (Credit for the frame idea goes to Elliot Smith - he used this technique on his Moon Crater mold and cast).

Creating and Gluing the Frames

Mixing Urethane / Creating the Molds

At Fab Academy Providence, we used a smooth-on 2 part urethane mold mix. Just mix equal parts of each container (A and B) and mix slowly in a figure eight pattern to minimize the bubbles.

What I learned about this material:

• Mix very thoroughly. Take your time (at least 10 - 15 minutes if you can stand it). The end result will be sticky if the parts are not mixed together well - My first two molds were sticky. (suggested by Neil Gershenfeld)

• Add heat. Heat both accelerates the process and creates a less sticky end product. I used a desk lamp positioned in close proximity to the freshly poured mold. (suggested by Neil Gershenfeld)
• Be careful not to leave the heat on longer than 15 minutes or so and let the wax and rubber cool before removing the rubber mold from the wax.
• I learned the heat lesson the hard way when my mold melted from excessive heat. (see photos below)

Beware of Melting Molds

All The Molds (Good and Bad)

Next Steps:

• Create a box and system for keying in the sides of the police box so it can be cast.
• Get LED, resistor and battery to wire up the light on the top.
• Cast in hydrastone

Anna Kaziunas France
[http://www.kaziunas.com]

When reading through instructables.com, I found a great pattern for a polygon construction kit. I thought I would use it for my first laser cutter / computer controlled cutting project at Fab Academy. The instructable I reviewed is for a plastic lamp shade, but I decided to use playing cards instead and make a construction kit minus the lamp. (Also, the cards are too opaque for a lamp and I didn’t want to take a chance with heat in such a small space.) In the end, I created a sculpture construction kit.

Laser Cutting the Cards:

Putting Together The Construction Kit:

This construction kit shape can be put together to form a variety of shapes.

My Final Construction:

Anna Kaziunas France
[http://www.kaziunas.com]

Published in the MAKE Blog.

Our assignment this time around was to design a circuit board, mill it, and program it in Assembly language. Each student had to become acquainted with the following work flow:

• Designing the board
  
• Machining
  
• Stuffing components
  
• Programming
  

Makeda Stephenson in the Providence Fab Lab

In a Fab Lab, circuit boards are either milled from copper-clad PCB stock or cut on a vinyl cutter from copper tape with conductive adhesive. We try to avoid the etching process in order to limit the used chemistry we have to deal with. Whether etching or cutting, the first step is to choose one of the options for creating a tool path to send to the machine:

1. Draw the circuit as a black and white PNG image and bring it into cad.py for tracing.

2. Draw the circuit using Eagle, a free PCB drafting tool, and export Gerber files, a standard format for PCBs. Gerber files can be converted into PNGs using gerbv or the online tool from circuitpeople.com. Bring the PNGs into cad.py for tracing.

3. Draw the circuit in Eagle and use Eagle's CAM processor to generate mill and drill files that can be sent directly to the machine. This process was described by Marc Boon in a workshop at the Amsterdam Fab Lab in 2008.
   

I designed a boombox in Sketchup and I milled it out on the Modela in hard wax, using a 1/16" bit. I like how the tool path left a fine pattern on the surface. This model radio measures 3.5" across, and it began as a block recycled from scrap bits of wax, hence the air bubbles and the stray chunk of wood on the upper right edge.

My year project will be a diorama of a mechanical dance party on a base, and the ceiling above the dance floor will be a functioning record player. The moving figures and the record player will all work on the same motor. I'll be casting these boomboxes in different materials to position around the diorama.

This article was written for the MAKE Magazine blog.

Since October of 2009, a handful of small groups of students have been taking part in an educational experiment called the Fab Academy. The Fab Academy is a distance learning collaborative that's built on the infrastructure of the Fab Lab network. Labs in Spain, Iceland, Kenya, Amsterdam, India, and Rhode Island participate in Wednesday morning lectures by videoconference. The curriculum is concentrated into two week topics with a project due at the end of each and a more ambitious annual project due at the end of the year. This series of articles for the Make: Online will follow each of the two week sessions in the curriculum and highlight the work, tools, and techniques being developed in the pilot year of the Fab Academy.

That's right folks, lasercutting is back with a vengance in the AS220 Labs. We're slicing and dicing our way through the dark days of winter, and this is your chance to get in on the fun! Didn't get a spot in this Saturday's sold-out class? Not to fear friends of the lasercutter, there's another class this Monday with 3 spots open!! Can't make it then? Then sign up for Broken Hearts Lasercutting on Saturday Feb.13th or almost-but-not-quite Leap Year Lasercutter on Feb. 27th and get your piece of laser glory. Come on, you know you wanna! Visit the online store to sign up!

All the endmills are now in this cigar box, which lives near the Modela. Grab the SVG file for the insert here.

My press-fit construction kit:

The parts have come out! Here they are separate:

Attempting to cast one out of urethane plastic with a layer of soap scum failed, as I hadn't mixed the plastic enough and weird white blobs of goo got stuck in the mold. I'm currently making another mold from the wax original after having stuck the bit that came off back on.

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I've been in L.A. for about a week now and I'm really eager to get back to the lab. I have so many ideas about how to incorporate every lesson thus far into my big project, especially making molds to cast multiples of tiny body parts for the characters I've been sculpting. I'll also be molding some 3-D rendered forms. Complicated and interactive automata dioramas!

I hand- sculpted the heads above in Cernit. I flameworked the glass eyes, and the "hair" on the right is made of trochus shells.

Jonathan's machine uses flexible couplings:

Decided to print an "old school rocket" from thingiverse for the lab:

Seen here in front of Jenine's "Providence" sign.

For my final project -- a pinball machine themed on an opera whose libretto is written by monkeys on typewriters -- I want to have a central chorus pit with five or six monkeys on typewriters. This seems like a perfect application for the molding and casting unit. My wife (Jill Colinan) is making the monkeys, so I thought I'd cast the typewriters for this assignment.

The Fluxamacutter is a design for a simple vinyl cutter that satisfies these criteria:

• Inexpensive ($50-$100 in parts)
• All parts can be cut on a 24"x12" laser cutter
• All press-fit construction: minimize hardware fasteners
• No precision parts required: all hardware cheap and widely available
• Arduino-compatible
• Plug-and-play replacement for existing HPGL-speaking cutters

The initial cutter will be able to take 15"-18" rolls, and will be designed to scale to 24" rolls.

After seeing David Carr’s political map relief I was inspired to do something similar. I thought it would be cool to model the Boston skyline. Since I also wanted to see how fine I could get the resolution, I took a jpg, and using the GIMP program, made it a black and white image with 50 colors and then put it through cad. I had it create a file with the following specs:

z min: -.75″

nz: 50 (one pass for each color)

tool size: 1/32

At 20, 20 speed the file was going to take about 12 hours. I was still going to try to cut it but Shawn pointed out to me that our 1/32″ bit didn’t have a long enough shank to cut at -.75″.

I went back, edited the file down to 10 colors and filled in the sky so as to leave just the buildings.

Then I created a .rml file in cad using a 1/16″ bit, .-.5 z min, and 11 nz.

After about 2 passes, the machine did a dramatic z drop and I had to stop it. Shawn suggested that I use more nz steps so I created a new file with 30 steps.

I piped the .rml files directly to the serial port through the command line as the computer thats hooked up to the mini mill has older software.

I piped the .rml files directly to the serial port through the command line as the computer thats hooked up to the mini mill has older software.

My 3D Modeling and Casting project is to make a model of the outside of the TARDIS. I used the scale and dimensions from G. Hartley’s plans to make an 8 inch model TARDIS.

G. Hartley’s Original Plans

I used these plans to create a 3-D model in Google Sketchup

However, as the milling machine cannot carve out negative space, the faces on the sides or the model could not be created. In order to create a machinable mold, I had to take the 3D model apart into three sections: the roof, the front door and a side (3 of the sides are the same).

In addition, I also removed some details that were in the original 3D model, like the light on top of the box and the all of the “Police Box” lettering. The light was not transferring properly into the CAD file and the lettering would be too fine for the bit on the milling machine. (I plan to create a sticker or letter by hand). I also scaled the model down from 8 inches high to 4.8” so it could fit within the block of machinable wax.

Shawn Wallace also suggested that I cast an LED into the model and use it for the light on top of the box. Brilliant.

The Roof, Side Door and Front Door

Sketchup exports .stl ASCII files and I needed them to be in binary. I opened the files in Meshlab and then exported them as .stl binary files. Next I ran the .stl files through stl2png.py to convert the depths to grayscale.

The final result (roof not shown)

The next steps are: 1. Mill out the 3 of the mold pieces 2. Cast with rubber, making 3 casts of the side view 3. Create a laser-cut box that will hold the mold together when it is being cast with hydrastone. 4. Cast with hydrastone.

Anna Kaziunas France
[http://www.kaziunas.com]

Creating a bzr repository:

First, inform bazaar as to your personage:

bzr whoami "Mr. Foo <mrfoo@as220.org>"

Then, make a directory for your repository: mkdir repository

Initialize the repository:

bzr init

Add the current directory:

bzr add *

Make the first commit:

bzr commit -m "Hello World"

Now, every time you want to add files, run

bzr add <files>

again, and

bzr commit -m "Message".

To check out your repository

start an ssh server (openssh-server in ubuntu, check the box in the preferences window in OSX), and run

bzr branch  sftp://user@ip-address/path/to/directory

Then

bzr pull

To update the repository, bzr commit again and then

bzr push

Have fun!

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Elliot and Shawn were debugging the modela, Elliot bet $1 that switching zmin to a negative number wouldn't fix the contouring problem (even though it'd been his suggestion to do so) and then Shawn bet $1 that adding a white background would fix Elliot's contouring problem. Shawn won both bets. I still haven't finished building Jonathan's machine, I cut another threaded rod that was too short, and our chemical filter isn't working. Susan, however, installed a new, quiet fan, so the leafblower has been obsoleted.

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The results of Shawn helping me work through the problem of having multiple button with several positions

I'm making a "Persistence of Vision" toy, which will show a programmed message in eight red light- emitting diodes. In the lab we have a roll of copper foil backed with a conductive adhesive. I used a knife to cut out a hand shape. (In this case, I found it faster to work this way than to use the vinyl cutter.) I covered a small metal container with a vinyl sticker to insulate the foil board from the conductive tin. I soldered some surface mount LEDs and resistors onto the copper.

Here is the hand after I drilled holes through the tin and soldered wires to the fingers. The wire on the bottom is ground.

This is the inside of the tin so far!

Our last module was on computer numerical machining and the assignment was to make something big on the ShopBot.

A few years ago, I made these star-shaped boxes on the laser cutter with thin (1/8″) plywood. For this assignment, I thought I’d scale up the design and make a few for my mom.

In my original design I used tension fits to pressfit it together, which was fine on a small scale. As I contemplated the modifications I’d have to make to scale it up, I realized that I’d need to actually model it in 3D and carve angled edges to accommodate the angled corners of a star shape. I did the 3D modeling assignment, but I did it in SketchUp because I didn’t have the time to become sufficiently competent in Blender.

Eliot, (one of the student in my class) hadn’t completed the 3D assignment so he made a model in Blender and carved it on the ShopBot. I figured I could do the same with my project and become proficient (sortof at least) in a more conventional 3D modeling environment while completing my CNC machining assignment.

Not so fast.

It was the middle of the first week before I reached a solid decision. (I was still working on hacking parts for our PCB Fab assignment from the previous module…aahhh.) After seeing what Eliot was doing and playing around a little bit I decided that this could only be so hard. Thats true of course, but “only so hard” turned out to be about 4 times more confusing than I had thought.

We played around with the program, completely ignoring the “extrude” tool for the first couple of days in favor of an agonizingly complex and excruciatingly inefficient combination of {select-push/pull-cut-delete-create face-face is warped-cut again-delete extra faces and edges-it looks good-no its skewed-cut-my brain is now crashing} rinse and repeat as many times as needed… method.

By the time we found our good friend “extrude” again, it was Friday. I planned to work on it over the weekend. Not surprisingly by Monday, one crazy weekend and two non-supportive computers later, there was no virtual star-shelf to be ushered into the analog world.

Shawn agreed to come up to the Boston lab to help me with the ShopBot on Tuesday. Switching to crisis mode I decided to make a sign for our lab instead.

When Shawn arrived in Boston I had an Inkscape file ready to cut.

I printed this on the shopbot but the pieces are still at Keeseh so I'ven't been able to test it yet.

skateboard.svg

I opened it in illustrator and saved it as an eps, opened it in partsworks and it cut fine.

I'll post attempts to assemble when I get the actual parts.

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I designed some shelves and cut them out on a Shopbot. While working, all pieces have to be secured to the bed of the machine (or to each other) because the tool is so powerful that the router could send a loose piece flying and seriously hurt someone.

I screwed my 4' x 8' sheet of MDO (medium density overlaid plywood) to the bed of the machine, and we programmed it to cut tabs between some of the parts so they would remain attached to each other. The finished sheet resembled a plastic toy whose tabbed pieces would be broken apart and snap assembled.

Here are some of the shelves after being cut on the Shopbot, and broken apart with a jigsaw.

Thanks to the Avineris for letting me borrow a palm sander. I used it to sand the tabs off the edges of the shelves.

I primed, painted, and installed the shelves in a corner.

I have more shelf pieces cut, but I haven't yet decided where to install them. Photos of my pieces on the Shopbot at Keeseh Studios will be posted after the holiday.

FELT

First attempt in felt:

I'm working on creating an chording keyboard

http://en.wikipedia.org/wiki/Chorded_keyboard

for my final project. Hopefully I'll be able to use the skills I learn in the FAB Academy to make one that actually works.

These packages are all in the Ubuntu repositories, so it's reasonable and sane to run:

aptitude install inkscape blender qcad python-scipy python-numpy python-tk python-imaging-tk eagle curl

We mirror http://fab.cba.mit.edu/about/fab/hello/ and http://fab.cba.mit.edu/about/fab/dist/ using Curlmirror. (a perl script that spiders webpages)

Some of the boards were coming out a bit hairy due to our initial use of the wrong drill bit (we were using series 1 when we need 1b), so I made a hairy hello world .cad file: hairy.button.45.cad

All attempts to create a working board without ripping off the traces or shorting out important pins have thus far been nonexistent, however, this may change shortly as Elliot's just milled a fresh batch.

I constructed this ruffle beard from fabrics that I lasercut and hand- painted. I wear it while biking to keep my face warm.

I drew these shapes, lasercut them, and assembled them into jointed figures. The joints consist simply of short pieces of bent wire.

This is a sheet of lasercut pieces for the jointed figures. The material is matboard from a frame shop.

This is a press- fit swingset that I lasercut from 1/4" thick wood.

I drew these shapes on a computer with a mouse, which took a very long time and hurt my wrist. I am investing in a tablet so I can draw more comfortably on the computer.

Hey hey hey Fabulous Folk! Welcome to the virtual expose of my fourth Fab Academy assignment.



For assignment #4 we were asked to create a press fit construction kit. My form and function goal was a basic set of pieces that would allow freeform construction of almost any shape.

Check it out :)

A Series of un-Unfortunate Events

I tested my initial idea in matteboard and found the combination of strength and flexibility well suited for my project. I wanted to play around with thin plastics but ruled out acrylic because it's too brittle. There were a couple scrap pieces of this white bendy plastic lying around the lab so I thought I'd try it. It worked like a charm. :) Upon further investigation I learned it's called Delrin. Delrin is an industrial strength plastic thats easy to lasercut and is used for stamps.

I originally created my design for a .05" thickness material. The Delrin sheet I had is .06" thick so it fit very well. Also we had some bugs in the laser cutter settings so it perforated the entire design instead of cutting it through. This actually turned out really well in the end because when I finally got it cut, the perforations acted as little "teeth" making the joints that much stronger.

I made a bit of a tradeoff in my design between ease of assembly and structural integrity. I intentionally offset the slots from the center so as not to compromise the center of the reed pieces which seems to already be a natural stress point. I'd like to do a little bit more research to see if this tradeoff is actually necessary.

GIK city invaded by Metabrick monster.

There wasn't a script to fetch the dependencies required by cad.py under ubuntu, so here's one: fetchdeps.sh And there wasn't an SVG of GIK, so I ran it through trace bitmap: gik.svg

Row row, fight da powa.
These were tinted red with a Bic permanent marker.
kaminaglasses.svg