After months of struggling with various different solutions trying to make this work, I gave in and bought a Makerbot Cupcake. It’s a 3D printer. I got that a couple of weeks ago and struggled again with some design problems that I didn’t anticipate. With some help from the people in the #reprap IRC channel and a better heater from MakerGear.com, I finished up the extruder (the part that melts plastic) and this evening I printed my first piece ever.

I’m super-excited and I had to share. My first piece was a very not-exciting 15mm cube. In response to a friend’s question, this is essentially the “Hello World” of the Open-source 3D printer movement.

(Note: A friend of mine noted that the “Hello World” of printers is actually a shot glass – the idea being that you toast your printer when you’re finished. This didn’t occur to me at the time, but he’s definitely right.)

Here are a few shots of the process:

So there it is. My first printed plastic object. The lattice thing there is called a ‘raft’. It’s meant to help the object cool down properly, so there aren’t warping problems. Anyway, If you have questions, thoughts, etc. Let me know!

Specifics about this tutorial:

There are a couple of things you should know going into this. First, I’m not going to teach you everything about EAGLE. EAGLE is a complex program, and it’s pretty awesome. There’s no way I could cover it all. Second, this tutorial came about as a way of trying to get more people into my local PCB order. We try to fill up our panels so we can get one out every 2-4 weeks, and we recently had to switch production houses. As a result, this tutorial doesn’t have any info on etching your own PCB, just on getting the Gerber files out. So come check out our PCB order, because it’s awesome. Lastly, for the sake of simplification, we’re going to make a board that uses only parts in the SparkFun Library. This is because I don’t want to try to teach you how to make parts on top of everything else we’re going to be doing. It’ll just be easier this way, I promise. Okay, one more thing: I assume you know how to use your computer. This isn’t going to be a “how to use your mouse” tutorial. I’m gonna go with some things that are EAGLE specific, but you need to know basics. At this point, I’d be surprised to find someone who’s unfamiliar with computing, but has a strong enough interest in electronics to be to the point of designing their own PCB.

Things you will need:

You’re gonna need these things before you get started.

• An idea for your shield – I can’t help you with this one.
• A copy of CadSoft’s EAGLE program – for laying out your PCB
• A copy of the SparkFun EAGLE library – for the components.
• Your preferred Fab house’s Design Rules – Our PCB order rules are here.
• An EAGLE CAM job for separating out Gerber files. Here’s ours.

After you download and install EAGLE, download and extract the Sparkfun library. You should get a file called “Sparkfun.lbr”. This is an Eagle Library made by SparkFun Electronics. I like this library because it has a wide variety of components and reliable footprints. (Footprints are the measurements for parts that end up on your printed circuit board, and it is absolutely crucial that they’re correct.) One advantage of the SparkFun library is that everything in it licensed under the Creative Commons 3.0 Share-alike license. This means you can use it commercially, so long as you share any adaptations your create. Another library I highly recommend (but is not necessary for this tutorial) is Adafruit Industry’s Eagle Library.

Once you have the Sparkfun.lbr, copy it into the “lbr” directory in the directory EAGLE is installed in.

Let’s Make a Schematic:

I told you I couldn’t help you with your shield idea. That’s not entirely true. Since talking in the abstract all day is a pain the neck, we’re going to make a simple shield that does a few simple things. Our shield is going to light up lights, and connect to sensors.

First thing we need to do is make a new project. Open up EAGLE from wherever you installed it, and you should get a window that looks a little like this:

Click on the File menu, hover over new, and when the sub-menu pops up, choose “project”

You now should have a new project folder under the projects heading in the control panel window. Go ahead and give it a name – I chose “New Arduino Shield”, but you can do whatever you want. There won’t be anything in the project right now, so let’s add something. Select your new project folder, and then click on the file menu, go to ‘new’ and choose “schematic”.

You’ll get a window that looks like this:

Your schematic is the blueprint for your circuit. It describes what is connected to what, and how. It does not describe what the PCB will look like. Don’t worry too much about how your schematic goes together. The important parts are to make sure the schematic layout is simple, and readable.

We need to get some parts in there. Namely, we’re going to want some terminal blocks, some LEDs and some resistors. First though, let’s add the Arduino pins themselves. You’ll want to select the “Add a Part” Button on the left hand side of the window. It looks a little like a plug with a pointer on it. It’s this one:

That will bring up a dialog called “ADD”. On the left-hand side of this window is a list of all the libraries that EAGLE has access to. The right-hand side shows information about the item in the left-hand side.

You’ll want to find the SparkFun item in the list. (As a side note, this list isn’t quite presented in alphabetical order. The methodology here puts all capital letters ahead of the lower-case ones. The list goes from A-Z, then from a-z.) Choose the SparkFun item, and click on the plus sign to expand it. If you don’t see any items in the left-hand side, go to the library menu and click on ‘use’. This will bring up a list of EAGLE libraries, and you can select the Sparkfun library.

Scroll down until you find the item called “ARDUINO_SHIELD” and expand it. In here you’ll find a few different versions of the Arduino layout. Schematically, they’re all the same, but on the PCB side (in EAGLE parlance, this is called the “device”) there are a few different variations. You can click through the different shield options to see what the device footprint looks like. I prefer the ARDUINO_SHIELDNO_SLK, because I can worry about making my own board shape rather than relying on the Arduino shape.

Once you click “Ok” the dialog will disappear and your pointer will have a schematic circuit attach to it (in EAGLE’s language, this is called the “Package”). Figure out a place to put it down and click your left mouse button. EAGLE will set down the package. You’ll still have a copy attached to your pointer, so hit ESC on your keyboard a couple of times to get to your window again. You should now have something that looks a little like this:

Click on the “add a part” button again, and this time, go hunting for a resistor. There is a sub-heading called “RESISTOR”. Under it, the most appropriate part is called “RESISTORPTH1″. When you click on it, the schematic package and the device footprint will be shown.

Click okay, and put down 6 of these guys. We’re going to put our LEDs on the PWM pins in the Arduino so we can control brightness (Note: You can actually pull off PWM on any pin on the Arduino, but it has to be done in software. We’re gonna ignore that for the moment.) Lay down the resistors just a little bit away from the Arduino package,

With the Resistors down, let’s put down some LEDs now. Click on the “Add a Part” button again and find the LED heading. In there, select the LED5MM Package, and click okay. Now you want to lay these out. It’s important that we put them the right direction. You can remember which side is which with a simple mnemonic device: A is for Anode. That is, the end of the LED with the arrow is the Anode. Another easy thing to remember is that the side with the line, is the Cathode. That line (|) turns sideways and becomes a negative symbol (-) or ground.

You should now have a schematic that looks something like this:

Now, for our shield we also want to throw in a way to easily connect some inputs, namely sensors. The easiest way (In my opinion) to do this non-permanently is to implement a terminal block. Terminal blocks are those things you can screw, clip, or lock wires into place. The connectors are conductive so pushing the wire in makes it part of the circuit. We’re going to add one terminal for each of the Analog inputs. Terminals come in blocks, and we’re going to use 3-point terminal blocks. Most often these come in 3.5mm pitch (3.5mm between the posts). Once again, click on the Add A Part button, and head on down to the “M”s

You’ll find under the M03 heading a series of parts that are 3-point connectors. We want the M03SCREW (Alternatively, if you want you can use the M03SCREW_LOCK – This is the same part, but the holes are just a tad wide apart. They make the part stay in place more easily when you flip the board to solder the pins.) As we have 6 analog pins, we’re going to put a pair of them on the schematic.

For the convenience, we’re going to throw in a power terminal. This will just give us screw access to the 5v line and the Gnd. A 2-point terminal block is a lot like the 3-point one we just added. It’s listed under the M02 heading in the SparkFun library, called M023.5MM. You’re an old-pro at this by now. Stick it in, and you should have something like this:

Okay, we finally have all the parts we want. Let’s wire up this thing!

You would think that you want to use the “wire” tool to draw connections between components. You do not. You want to use the “Net” button. The net button is a little tidier than the wire button, does things right, and makes everything better. The Net tool button looks like this:

Select it. (Even though it looks like it, it’s not grayed out. Also, don’t confuse it with the button immediately next to it called “Bus”)  We want to draw lines between the PWM pins on the Arduino to the resistors. The PWM pins are marked by a small asterisk (*) on the chip. They are D3, D5, D6, D9, D10, and D11. When you click on the wire, it starts another segment. Start at the pin on the Arduino, and click. You should now be dragging a line. Click again to create another segment. When you’ve gotten to where you want to end, hit Esc, or Triple click. This will stop the line. Do this for all 6 PWN pins and you should have something like this:

Now attach each resistor to it’s associated LED. You should now now have this:

Now let’s attach the terminal blocks. Everything should go in order, except for the power block. Because of the way the pins are setup on the device, we want to pull the bottom most ground pin from the Arduino and the 5v line. When you’re done, you should have something that looks like this:

We’re almost finished. We just need to complete our circuit to make everything work right. To do this, we need to run a ground line over to the LEDs.  Grab the wire tool again and draw a line from the top GND line on the Arduino and carry it around to the side with the LEDs. Why the top GND line? Well, the way that the schematic translates to the board later, puts one of the GND pins on the side with the digital pins, while the other two are on the side with the analog pins. So this is for convenience.

Now connect each LED to the ground line.

That’s it! We’re done with the Schematic and we can move onto producing the PCB. Be sure at this point (if you haven’t already) to save your schematic. You never know when something will go wrong and take away all your hard work. You may want to try laying out the whole thing over again, just for the sake of doing it. Going through the process a few times will really help you get a feeling for EAGLE’s quirks and the processes in it.

Making the Board:

Now the fun part! I call this the fun part because I enjoy the process of figuring out how to put together the circuit in a way that makes sense. With an Arduino Shield, there are a couple of things already solved for you: 1) You don’t really have to worry about Orientation, the shield is only going to plug in one way. 2) A lot of your layout is already fixed (This can be a mixed blessing though.)

At the top of the window, you’re going to see a button that has two things on it. The button is called the ‘board’ button (in the schematic window) It has a symbol on it that looks like a plug (actually, it looks like a AND gate, but if you’re not familiar with electronics schematics at that level, it’ll probably look like a two-pronged plug) The other symbol looks like a 6-pin IC. The button looks like this:

When you click on it, you will probably get a warning that looks like this:

Click “yes” and it will open up a window like this:

We need to move all of those parts into that white square. Click on the “group” tool (this is the dotted square)

And click and drag around all the parts.

This should highlight all the parts. Now you need to click on the “move” button. It’s the one that looks like a cross with arrows on each end:

And right click on one of the parts. This will bring up a long list of items.

Click on “move group” should attach the whole group of components to your pointer. You want to move all of these things inside the white box. When you’ve done that, you should something something like this:

Before we continue, we’re going to turn on the grid. You don’t have to do this if you don’t want to, but when you get to more complex boards, you’re going to really want to use the grid. It is absolutely crucial in PCB design. To begin, click on the Grid button in the upper left hand corner:

This will bring up a dialog. You’re welcome to set it to whatever you like and you might want to mess around with it to get a feeling for what it can do. I like to work in 0.1 inches as it’s the most common header in the US. Additionally, there’s an ‘Alt’ setting which produces a secondary grid you can work with. I usually set it to 1mm because that’s a common measurement as well.

Once you click okay, you’ll get a space that looks like this:

If you don’t like the size of the grid, you can certainly change it. I’m going to turn off my grid because it can be a bit distracting. This doesn’t mean that the grid is actually gone, just that it’s not displayed. When I get to positioning the components, it can be useful to have. Do whatever works best for you.

When I’m making an Arduino shield, I prefer to have it oriented the same way as the Arduino itself. That is, the top is viewed either as the side with the USB connector, or the side with the digital pins. For whatever reason, when SparkFun put together their Arduino component in EAGLE, they make the component default to a position with the digital pins on the left-hand side. In order to make it easier to work with, I rotate the whole thing. EAGLE makes this easy because whether it’s up or down, the names and values remain upright and readable. At this point, I’d tell you to use the rotate tool, but for whatever reason, I can’t get it to work properly here.

The method I use to rotate components is to choose the ‘move’ tool, click on the component, and then right click. As you right-click, the component you’re using will rotate counter-clockwise. So now you should have something that looks like this:

Now you’re going to want to begin placing components. This is largely up to you, and I’m not going to walk you through it step by step. You’ll see my solution below. Basically, move these components around until they make sense in their layout. The yellow lines (“air wires”) represent how the components are connected, and to what. The simpler the path is, the easier it will be to understand later. Try to keep them as straight forward as possible. Don’t worry if they overlap, that will all be solved in a moment.

See what I mean? Easy to read!

I should note here that most terminal blocks are designed to fit right up against each other, This is why I’ve placed the blocks so close. The particular ones that SparkFun sells actually interlock. You’ll want to make sure you properly line them up so the footprints are marked together. Because the footprints are tightly controlled, it can be a little difficult to position them correctly. These terminals IMO, are a little wonky, so here’s the simple solution: Put the 3-point terminals at 15mm and 26.6mm. I think there might be an error in the library with the 2-pin terminals. This image shows the block right next to the 3-pin terminal, but I don’t believe it will actually fit. If you choose to get this board produced, please fix the spacing or the part in the library.

You may want to resize your outline at this point as well. This is easy. Just take the corners of the outline and drag them to a size that works for you.

Now we want to take care of the routes. You could use the “Auto-route” button if you wanted to, but I prefer to do my trace-routing by hand. Because of that, it takes a little longer, but usually ends up neater in my opinion. First you’ll want to click on the “Ratsnest” button. This button takes all these little yellow lines that connect your circuit and moves them around to make things a little simpler.

Clicking that will recalculate the mess into this:

Now click on the Route Button

Now find one of the yellow airwires that connects to the ground line.Click on it, and you’ll start to draw a route. Don’t worry about crossing any of the yellow lines yet, we’ll take care of that in a minute. What you’ll find is that EAGLE automatically continues your line. As the LED’s ground line connects all of the LEDs together, we can just follow it around the board. Now let’s do it again with the lines coming from the 6 analog pins. Draw 6 lines with the route tool. You may have to get a little creative in how you draw the lines so they don’t connect with each other or other pads. Again, at this point don’t worry about crossing the yellow air wires just yet. When you’re done, you should have something like this.

Okay. We’ve got 7 lines we still need to route, and space is getting pretty tight. What are we going to do? Fortunately, we have more than one side of the board to route on! In the upper left hand corner, when the route tool is selected, you’ll see a drop down menu. Currently it should say “Bottom” (meaning the bottom of the board) but if you click on it, you are able to select “Top”\

You have to be a little careful because there’s less room on the top for routing than on the bottom, but with some creativity you can make it work. I recommend you take advantage of the gaps created by the resistors to take a route over to the other side.

If it’s kind of hard to see, here’s a picture without the text that make show the routes a little better.

Okay. We’re almost done. We want to put a couple of things on the silkscreen, so we know what to plug in to the terminal blocks. This part is easy. Click on the Text button (The “T”). Type what you want, and place it. By hitting escape, you’ll get the dialog box again, and you’ll be able to place another thing. You might also want to fill in any blank space you have (or not) I like to put in something identifying, just for fun.

So here we are. We have completed our circuit and we’re ready to go! We’re almost finished (again). All we have to do is turn this sucker into Gerber files and shoot them off to the fab house.

Gerber? Isn’t that baby food?

Yup, Gerber is a brand of baby food, but it’s also the common name of the files you send to a manufacturer so they know what to do to make your board. It was initially created by a company called Gerber Systems Corporation. They used it to drive a photo-plotter. These days it’s properly referred to as RS-274X. There are lots of different “layers” in a gerber file, but the common ones you come across are as follows:

• Top-Silkscreen – This usually shows your documentation… part placement and footprints
• Mask Top – This shows the machine where not to put soldermask, like the pads you’ll be soldering onto
• Mask Bottom – Same as above, for the reverse.
• Top Copper – This shows where the machine should leave copper so your circuit connects
• Bottom Copper – Same as above for the other side.
• Excellon Drill – This is the file that tells the router where to go through your PCB
• Outline – Your board outline.

Allright, enough talk. Let’s do this.

First we need to run electrical and design checks. These make sure that nothing is electrically wrong with our design and that our fab house can actually produce it. Note: This doesn’t mean your design will work. It only means that EAGLE doesn’t see electric circuits crossing paths.

Click on the electrical check tool:

and it should bring up the ERC errors page. In this page there are a lot of warnings. Here it’s just telling us that there aren’t any values listed. I intentionally did that because I figured that someone may want to put their components. Who knows how big or how bright you want those LEDs. I’m not gonna tie you down.

The way we take care of these is simply click on “Approve” for each one. Be careful how you do this, you don’t want to approve something that is wrong.

Next we’ll run the design rule check. Click on the design rule button

Since EAGLE doesn’t know who’s rules you want to play by, you’ll have to choose a design rule file, or a .dru. I use our PCB order rules, which can be downloaded at the top. Click on the “Load” button, and choose your file.

You’ll get the design rule check screen. Just press the “check” button.

Uh-oh. Looks like I wasn’t paying close enough attention. There’s an overlap in the circuit layout. That is to say that something on my board is connecting in a way that is not connected on my schematic. Fortunately you don’t have to hunt around for it. EAGLE draws a nice little box around the area in question.

In this case, it looks like I ran my GND line right through one of the holes where the VCC line comes in. The way we fix this is “rip-up” the line and redraw it. The Rip-up tool looks like this:

All you have to do is click on the offending line, and then select the routing tool again an lay it down in a functional manner.

Okay, now that we’ve fixed that, we run the Design rule check again…

And it comes back good! Hooray!

Now we can finally produce those Gerber files. click on the CAM processor button

and it will open up the CAM processor Window (funny how that works.) We want to use a specific CAM job, so we have to go to File->Open->Job…

Choose your cam job, and you should get an updated CAM processor window:

The only adjustment I recommend here is that you additionally select tDocu-51 on the Silkscreen-CMP layer. This will make sure that the Arduino Silkscreen stuff ends up in the silkscreen with the rest of our materials. When you’re ready, press the “Process Job” button. EAGLE will output the gerber files and output them into your project directory. EAGLE will have produced both .ger files and .gpi files. The gpi files simply contain information about the ger files, and are unnecessary.

If you want, you can see what these files look like by going over to circuitpeople.com and loading them up. It’s nice and simple. No signups, no ads. Just an easy way to view your gerbers. I highly recommend you do check your work to make sure it looks the way you want it to. I have gotten back boards that didn’t have everything on the silkscreen layer that I expected them to. Here’s how a couple of the gerbers looked from this project. On the left is the top-copper gerber, and the right is the top-silkscreen.

That’s it! You’re finished. Zip ‘em up and send them off to your board house, or if you want it to be easy for yourself. Send them off to Laen, and he’ll include them in our monthly PCB order! I guarantee you, it’s hard to beat $5/sq in. for 3 boards. The turn around time is a little more than a week from send off date. And they don’t go out to China. (Judge for yourselves if that’s a good thing. I can go either way.)

If you’d like to look at the files I made while doing this, they are on the download page.

So there you have it. Make a circuit, order it, and in about a week-and-a-half, you get something that looks like this. If you need some help, you can usually find me during the week as sircastor on IRC on the #dorkbot channel or you can email me!

Anyway, the group also does a monthly PCB order. You make your design, send it off to Laen, who manages all this, and he sends it off to a PCB fab house out in Colorado. This all for $5/square inch and you get 3 of your design.

I’d been toying with the idea of an Arduino shield that mixes the best parts of the prototyping shields I’ve seen. I also wanted a board that I could plug several servos into for servo control. What I ended up with was the “Arduino Servo-Proto-Shield”. You may have seen the rendered version in my last post.

The shield breaks out all of the 28 pins into 3.5mm screw terminal blocks. It also has long-tail female headers for additional shield mounting. The 12 digital pins (2 through 13) are broken out into Servo-motor headers. For fun I threw in some 0.1″ vias if I want to add some permanent circuit.

Unfortunately, I made one minor mistake in my design. My 2-terminal blocks had the wrong drill size set for the hole, as a result, they’re just a bit too small to accomadate the terminal blocks. So unfortunately the breakout for my GND, Aref, and Serial communication is out of commission until I find a way to shave down the posts on the terminal blocks.

I soldered it this evening and plugged it into my Arduino. It looks good, and I’ve tested all the connections – they all work fine. I just have to make this do something now! Any of you who read this and have an interest: What do you think could be improved? I’m looking for ideas and thoughts to make this a better shield.

The nerve…

So here’s the deal. POVray for the Mac is either being developed poorly, or more likely is simply not the center of the universe for it’s developers. On the POVray website they blame Apple for not properly keeping up the PPC emulator. I want to support these folks for their hard work, but seriously… we’ve been using all-intel Macs for 4 years now. Time to move on. At any rate, this problem occurs in a few machines, and it’s not quite clear which ones. The problem has something to do with preferences, and Intel Macs between 2006 and 2007 (of course, my Mac is an early 2008 model, but who’s counting?)

Because I couldn’t find any easy answers to getting POVray to run, I was pleased to have found a solution. Here are the steps needed to get your board rendered in 3D:

1. Download these things:

• MegaPOV (download link)
• Eagle3D (download link)
• POVray (download link)

2. Install MegaPOV, and Eagle3D (if you haven’t already)

MegaPOV is a derivative of POVray, and it’s fortunately written in Cocoa and is a proper universal binary. Because it will run properly, we can use it to render the images Eagle3D turns out. MegaPOV is an easy click-and-drag to install. Just stick it in your Applications folder. For Eagle 3D, I recommend you move the folder into the EAGLE folder in your Applications directory. Good place to have it.

3. Copy over needed include files

In order to use MegaPOV for Eagle3D, we need to copy some include files from POVray . In the POVray folder, you’ll see a folder called includes. Rename this folder to “pov-includes” (or whatever you would like), and copy the folder into the MegaPOV folder.

4. Make changes to the Eagle3D UPL

In POVray, you can name variables starting with lowercase letters. MegaPOV is not as courteous in that respect, and so if you try to render an Eagle3D pov file, it’ll throw and error:

expected 'unidentified declaration', environment found instead

It’s relatively easy to fix this. The variable named environment is the culprit, and we’ll need to change it in the ulp file in the Eagle 3D folder. As Eagle3D is a few years old, everyone is probably using the 3d41.ulp. If you’re not, you’ll need to change the file you’re using.

Find the following lines in the code:

46: "#if(environment=on)\n"
1023: if(opt_amb==1) printf("\n#declare environment = on;\n");
1024: else printf("\n#declare environment = off;\n");

Change those lines to look like this (respectively):

46: "#if(Environment=on)\n"
1023: if(opt_amb==1) printf("\n#declare Environment = on;\n");
1024: else printf("\n#declare Environment = off;\n");

That’s it, no other changes to be made in the code. You just need to capitalize the E in “Environment”!

5. Set additional include paths

We need some of the include files that are floating around here. In MegaPOV you can set two include paths. It provides a convenient open dialog. You need to select:

• /Applications/EAGLE/eagle3d/povray/
• /Applications/MegaPOV_C_UB/pov-include/

Settings for alternate paths

6. Make your board!

That’s all you need to do. From this point, you need to simply run the Eagle3D script in EAGLE, and it’ll generate your .pov. Open your .pov in MegaPOV, and it should render just fine.

My custom Arduino Prototyping board

The website does note that these colors are representative only, which is pretty reasonable. If you have your monitor colors messed up, and the red comes out looking orange, they don’t want you to complain.

Anyway, without further delay here they are:

Black

Silver

White

Red

So there you have it. The LEAF is coming in different colors. These 4 are in addition to the blue we’ve all seen and thought “Oh, I hope I can get it in some other color.” Our reservation is in. We chose Black. (It bears noting that my wife, Hykel, preferred red)

Or possibly:

iPhone detractor: “Apple fanboys are so thick-headed. They always talk about how awesome the iPhone is, but [Android|Palm|WinMo] has been doing since version x.x and it has feature y…(ad nauseum)”

Yes. I know that whatever platform you use/prefer has had feature X and now the iPhone is getting it. Despite what you think, most of us already know that the iPhone isn’t the first to have feature X. Go out right now (out, not on the internet) and find an iPhone user who thinks that multi-tasking is a new, unique feature to the iPhone. I bet you can’t do it. If you can, I’m willing to bet that the person you’re talking to has very limited experience with any kind of smartphone. On the surface, it may seem like you’re trying to be helpful saying “This feature has been around for a while on my platform, you should see what it’s like, I think it’s great.” Or if I want to paint you in a more pessimistic light, you’re saying “Your phone isn’t so great, my phone already does this, watch me do my multi-tasking dance of triumph! Sucker!”

I wish you were genuinely trying to share your preference with me. I might take the time to look at it with you and maybe you could persuede me. I wish you were gloating, because then I could ignore you. But you’re not doing either of those things. What you’re really saying is “I’m mad because in spite of my platform having cool features, your iPhone keeps getting the spotlight. It’s not fair!”

You try to hide it behind psuedo-logical arguments, and blaming my supposed “fan-boyism” (fanboy has really become the beating stick of the anti-apple folk), but when it comes down to it, you’re just unhappy because you’re not getting your way. I don’t blame you. If I cared about sports, and my favorite team lost a game, I’d be upset too. When it comes down to it though, the iPhone isn’t amazing because it only does stuff that no-one has ever done before. We know that Multi-tasking, and app organizational folders are not new ideas. The iPhone is amazing because it blends things together very well. Android is an impressive operating system, WebOS is cool, I haven’t spent a single second interacting with Windows Mobile 7 but I’m sure it’s cool too. The one thing I’ve seen that they lack is the cohesivness and smooth experience that makes up the iPhone. The experience comes largely because Apple holds the cards on all sides of the equation. It hurts Apple in a lot of ways, like the app-store approval process, but if you look at the industry you’ll see that virtuall everyone else is trying to replicate Apple’s pattern. Apple certainly wasn’t the first to build an app store or make a touch-screen phone, but think back to before the iPhone. Do you remember going to an app-store like interface? How about using a touch-screen phone? What were the all-in-one smart phones like then? What are they like now?

Regardless of how you feel about Apple, they still make one heck of a device, and they’ve changed the face of the mobile industry. Because of that, you can bet I’m going to be excited about cool features being added to my favorite phone.

Several months back when SparkFun announced Free Day, a few friends of mine got a bit of a glimmer in our eyes. We’ve been intrigued by the premise of the RepRap printer for some time, but in generally felt out of reach. The distance was measured by a number of things, including money, and the theory was that we’d be able to get some free stuff out of SparkFun to help with the cost. We quickly realized that SparkFun didn’t sell much that we actually needed (and you know how it turned out anyway.) So we decided to embark on the journey anyway. Isaac decided to take on the electronics and the extruder, while I decided to handle the cartesian robot.

“What is a cartesian robot?” you say. Well, it’s a robot whose job is to move something around in three-dimensional space. In the case of the RepRap, it’s a device called and extruder that takes plastic filament and melts it down to a liquid form so it can be laid out in some manner kind of like a hot glue gun. So if you can lay down melted plastic, move around the source of that melted plastic, you can build an object layer by layer.

Enter the McWire Cartesian robot. A few years back a guy named Tom McWire came up with a pretty neat design for a 3-axis CNC machine. It was small, built on commonly available parts, and well documented. Then, a guy named Zach Smith adapted the design for use as a RepRap. A couple of months ago, I decided to build one.

And there it is! My biggest frustration I think was the lack of several things when it came down to the construction. A few of my complaints:

No measurements for the design anywhere.
Acrylic was recommended, but not easy to obtain or DIY.
The lead of the design has since abandoned it for greener pastures
The design is overly-complicated for what the project is trying to accomplish.
Some things about the design don’t make sense

A lot of these things are carryovers from Tom Mcwire’s original design. For him, as near as I can tell, the decisions were ones of “Well, I have this stuff….” which is very easy for a guy who has a shop full of materials to use. For a person who needs a parts list, this becomes a very bad idea. Mostly because a person who goes out an buys parts for a project expects the project to make sense from a purchasing standpoint. This is rarely the case where someone is making something from materials they have. Utility is more important than the material itself. Thus, the over complicated machine.

Early construction

I’ve been working with others within the RepRap community to develop a good official replacement for the McWire. Right now we’re focusing on an easily-constructed design nicknamed “Wolfstrap” after it’s first builder who’s name is Wolfgang. This design hopes to take into account more common materials, simpler-design, and fewer proprietary concepts. Beyond the pictures you can find here, I’ve put together a model in SketchUp.

Was building the McWire fun? Sure. I had some fun, and I had some really irritating moments. I’m glad I did it, and I’m also glad I’m done with it.

The song was written by a man named Laurie Johnson. He is a British composer and the song is called “Happy Go Lively”. It’s owned an licensed by a company called Associated Production Music. Production Music, is a term given to music that’s essentially made for the sole purpose of licensing it out for productions (movies, television, etc)

Considering how well-known and familar, but unidentifyable this song is, I thought I’d post it to a page and stick as much google-glue as I could on it. If you found this page through a search engine after having some difficulty, give me your search terms and I’ll put them in the keywords, so people like us don’t need to struggle to find this delightful little song.

Here’s a little clip:

See, back in November SparkFun Electronics, a hobby electronics store, decided that they wanted to do something special. They decided to have a “Free Day” where they would give every customer up to $100 of product on their site. This spread like wildfire on the tubes, and when the day finally arrived there was far more traffic than Sparkfun could handle. I want to say that there was far more traffic than *anyone* could handle. The result could be categorized as a disaster. Many people could not load the page at all, many couldn’t log in, and even if they were at the logged in point, checking out was just as bad.

Lots of people are angry. They put in a lot of effort and ended up with about 2 hours of not getting free stuff. I’m not too tolerant of people who are whining because they feel entitled to the SFE free stuff. My expectation is that many people who got things will be reselling them at worst, or at best the items will end up in a drawer waiting for a project that will never happen. I’ve heard rumors and whispers (okay, comment posts) that FreeDay was going way farther than expected, ending up on frugal shopping and coupon websites. The result (I imagine) is that there were a lot of people looking to get free stuff, not understanding what SparkFun Electronics was, or what they sold. By the time they got to the site, they were just compounding the problem.

So now, on ebay there will be a few dozen more Arduinos up for sale. I think this is a good thing…”What?!?!” you say? Well, economics is an interesting thing, even on eBay. See, if you have a dozen Arduinos suddenly hit eBay, the supply has suddenly increased. Market forces work their magic and for a bit, Arduinos on eBay will be cheaper. Maybe $15 instead of $30. A quick glance at eBay shows that Arduinos are already selling cheaper there than from SparkFun, or anyone else.I think the thing that really gets me is the number of people who feel that they should have gotten something, but didn’t. I’m sure I’ve felt a sense of entitlement where it didn’t belong, but I also like to think that I’ve grown out of that. Many people have not.

Am I thrilled about Free Day? I’m thrilled about the idea. That a company would say “Hey, we’ve had a great year, let’s give back to our customers, and have some fun with it.” was brilliant. I think it’s that kind of thinking that will allow businesses to function exceptionally well in the 21st century. Do I think it went well? Obviously not for me, but I’m not relying on free items to forward my projects. When I have the funds, I’ll buy the things I need. I hope next time they’ll do it a bit differently so the traffic isn’t as bad, and I get a chance at something. It went well for a lot of people, and it generated some press for SparkFun (though it may not all be good press.)

In the end I think that maybe the lesson to be learned here is that there’s still no such thing as free. Many people ‘paid’ the price of waiting online for two or three hours only to get nothing. I don’t think SparkFun could have anticipated the traffic they’d get. Initially I didn’t even predict the kind of hailstorm that “Free” brings on the internet. I hope SparkFun finds the future to be just as bright. I don’t think this will turn out to be more negative than positive. I hope if they do anything like this again, it’ll work out to be a little smoother, offering something for everyone.

There’s a major downside of live Christmas Trees: Watering. I know, it’s really not a huge deal, but if you fail to properly water your tree, you end up with a dry, ugly, failing tree a week before Christmas. We don’t want that, so I’m very interested in keeping the tree moisturized. It presents a couple of problems: 1) You need to remember to water the tree   2) You need to get under the tree to water it. As I said before, this tree is a behemoth. We didn’t trim the bottom branches much, but even if we had, sliding under on your tummy and precariously balancing your pitcher to get water in the stand is not an easy feat.

The Solution: The distance-tree-waterer.

I didn’t invent this idea, and I’m certainly not the first to come up with it. I do take a little pride in saying that I thought of it before I went out to the internet to find it. However, I didn’t think of sticking the water-bucket under a present-shaped box.

Okay wait, tell me what’s going on here…

Allright. So I mentioned that I didn’t want to crawl under that big ol’ tree to pour water in it. Well, there’s this magical physics trick that allows you to move water from one place to another. It’s called a Siphon. Water likes to go downwards. You’ve seen this in streams that flow off mountains. Gravity pulls water in a certain direction, and then, so long as their is a difference in equity of two bodies of water, it will continue to pull more water along with it.

So the trick here, is that the bucket hidden behind the present facade has a water level that’s higher than that of the water in the tree stand. I started the water moving by sucking it through a length of tubing. So long as the water in the gift/reservoir is a higher level than the treestand, water will flow. When the tree stand equals the reservoir, the water stops flowing. The water will stay neutral until the reservoir is filled back up.

All in all, this project took me about 45 minutes to put together. 10 minutes to setup the actual mechanism, and an additional 35 to get a nice facade put together so it didn’t look like I had a random bucket of water sitting on the floor. The “Present” is made of 3 sides of  cardboard, and a top which goes over them. It’s wrapped in regular wrapping paper. On either side of the water line, there’s a short length of copper wire (what I had available at the time) that serves as a clip to hold the line in a particular position. As the system is dependent on the flow of water, we don’t want these tubes falling out and flooding the living room.

So far the system is a resounding success. I haven’t had to crawl under the tree or even at this point refill the water. As the tree draws water, the tree stand will refill from the reservoir. I just need to put water in as the reservoir gets closer to empty.