Will's Blog

A week of 3D printing with the OrdBot Hadron

noreply@blogger.com (Will Winder) — Tue, 30 Apr 2013 10:32:00 +0000

It has been about a week since my OrdBot's first successful calibration print and it seems like a good time to write down some of my initial problems, experiences and solutions. However before I get into that a review of my 3D printer stack.

Hardware
OrdBot Hadron
3/8"-12 TPI ACME Z-Axis screws
1.8 degree Nema17 X/Y motors
1.8 degree Nema23 Z motors
Qu-bd MBE Extruder (with some modifications)

Electronics
AzteegX1 v1.0 (644P processor)
Lava heatbed, I have only used PLA at this point so this is still disconnected.

Software
Mac OSX
Marlin firmware
Slic3r v0.9.9
Pronterface (March 2012 release)
Repetier-host Mac (0.56, lower versionthan linux/windows releases for some reason)

Now for the problems encountered during the past week, approximately in the order which I ran into them.

Pololu A4988 - I have used these before on my ShapeOko CNC machine. They have been so reliable that I completely forgot how to set them up, as such I blew up 3 drivers while setting up the electronics. So be careful, check the polarity and for the love of everything don't measure voltage when your multimeter is in continuity mode!

Leveling the bed - This was tedious but not particularly difficult. The LAVA heatbed has 8 M3 screws along the perimeter so calibration was just a matter of carefully tightening them until the height is just right. To measure the height I lowered the printer nozzle until it had just enough space for a piece of paper to slide underneath with little resistance, at this point I manually jogged the nozzle along the perimeter adjusting the M3 screws as necessary until the bed was level.

Setting the Z-Axis endstop - This step is ongoing and was very tedious without a way to precisely raise or lower the endstop actuator (a screw in sliding t-slot nut). I have it set fairly close, but still find myself hitting the "stop motor" button and manually turning the Z-Axis screws while the first layer is printing. Eventually I will print out something like this and dial in the Z endstop a more reliably.

Configuring steps per mm - This was the longest part of the process, and I'm still not sure why. Fortunately it wasn't difficult, just tedious. I know the steps per revolution on my motors (200), the microstep resolution for the steppers (16x), the pitch of MXL belts (2.032mm) and the number of teeth on the pulley (16). Using the equation on the buildlog.net configuration page gave me a number which ended up being way too small. My calibration object of choice was the nickel test thing on thingiverse, I just kept printing them out, measuring the insides and adding a ratio multiplier until satisfied that things were the correct size.

Pololu A4988 overheating - Once I had my machine calibrated I started trying to print larger objects that took more time. Without fail after 5-10 minutes after starting the machine would start losing steps. Eventually I noticed how hot the stepper drivers were and mounted a fan pointing at them which fixed the problem.

The notorious QU-BD MBE. This thing gave me a ton of trouble, so much so that I ordered a J-Head after the first day of trying to get it up and running. That said I've managed to get it to print very reliably and haven't yet felt the need to install the J-Head.

QU-BD pre-upgrades - Before I even had my printer assembled I performed some upgrades on the QU-BD. First is the QU-BD Modification Kit from the MakerSlide store. Secondly I hobbed the stock raptor gear with a small tap in my electric hand drill.

QU-BD overheating jam - There is a fan and heatsink on the extruder. I wired it (incorrectly) to the Azteeg X1 fan input, making it configurable in gcode (M106 and M107). My slic3r configuration toggled the fan on and off, so occasionally the cold-end of the extruder was heating up too much causing a jam. My current solution is disabling the cooling option in slic3r, but eventually I will wire the fan directly to the 12v input.

QU-BD underheating jam - My printer is in the kitchen and there is a nice crossdraft going through the room now that it is nice outside. The crossdraft was causing the nozzle to drop below 165 degrees, when this happens things usually jam. I need to wrap the hot end in some sort of insulation which will hopefully fix this problem.

QU-BD slicer jam - While printing the nautilus near thing I was noticing frequent jams during the infill stage. The thing about this object was that there was very little amount of infill needed so the filament moved very slowly. My best guess is that the filament was sitting in one place so long that it heated up too high in the extruder which caused the jam. After reconfiguring slic3r to leave the object hollow there were no more jams on this print.

Pronterface vs. Repetier-host - This could probably be a blog post on its own. They both work but suffice to say that repetier-host is leaps and bounds ahead of pronterface in terms of usability. The one problem I had was that repetier-host allows you to configure the controller buffer size, the default is 63 which causes stuttering when printing complex surfaces with short line segments. I upped this value to 127 when I was 75% finished with the owl print (below) and you can tell just from looking at the surface of the model where I made that change because the surface quality improved dramatically. I just wish I had found that setting before printing all those feathers!

This owl is my longest print to date at 3 1/2 hours. This print was running while a draft was running past the printer, I probably fixed 5 or 6 jams while it printed which caused a several noticeable defects (most of them on the owls back).

After many attempts I finally got the Nautilus Gear to print. Now that everything is dialed in I could print one out in about an hour (~12 minutes for the two clips and ~18 minutes per gear).

Building an OrdBot 3D Printer

noreply@blogger.com (Will Winder) — Sat, 27 Apr 2013 23:01:00 +0000

I've been a fan of MakerSlide ever since building my ShapeOko CNC Mill, and have been interested in 3D printing since first hearing about the RepRap project in 2007. So when I first saw the OrdBot, I knew that it would be the printer I build. It didn't hurt that I had 10 feet of extra MakerSlide and a whole bunch of the special bearings and eccentric spacers left over from my ShapeOko build.

One of my goals was to build all the custom parts myself, the blue and black pieces in the photo above. Cutting aluminum on my new CNC machine pushed it to the limit, but worked out in the end. One of the larger OrdBot pieces is the handle, here is a shot of the ShapeOko making short work of it:

There are a couple parts that I modified or upgraded during the build. Most notably the Z axis. After reading about bent Z-rods I decided to get some ACME rods, and I wanted to use some spare Nema-23 motors that I had on hand.

The NEMA-23 motors for the Z axis were easy, I slightly modified the stock motor part to fit the new motor:

Attaching the ACME rod was a little trickier, but managed to hand fabricate a bracket with some 1/8" thick angle aluminum:

In the spirit of being thrifty, I signed up for one of the (now notorious) Qu-bd extruders during their kickstarter campaign. So far I've managed to get the extruder to work with a couple of simple motifications. Some more hand fabricated mounts and I had the extruder attached:

For the electronics I am using one of the first generation Azteeg X1 boards. So far I've been very happy with it (save for an exciting wiring mistake where I had the polarity backwards). I opted to run the wires through the hollow MakerSlide extrusions whenever possible. Here is the nearly completed wiring, I really appreciated the zip-tie holes:

After a few days of tweaking and calibrating, I'm getting some nice results. Here are some action shots with the machine up and running:

ShapeOko CNC Mill

noreply@blogger.com (Will Winder) — Sat, 27 Apr 2013 22:20:00 +0000

April of 2012 I signed up for the first batch of ShapeOko kits from inventables.com. Unsure of how popular the kit would be, inventables had a kickstarter-style order of 150 (or so) kits. That number was reached handily and several more batches followed. Since the ShapeOko has become a standard item in their store.

I've wanted a CNC mill for a long time, but could never justify the expense. Now there are products like the MakerSlide linear rail system that made it possible for low cost machines. The first round of kits were only $200 for the entire mechanical platform - add your electronics and a dremel tool and the machine can start cutting.

So thats what I did.

The stock kit after assembly:

One of the nice things about the ShapeOko is how hackable it is. For instance if you want to make the cutting area larger you can just replace the MakerSlide with longer rails. So I added longer rails, a second Y-axis motor, a torsion box to mount everything on, a bigger router and some woodworking T-slot to hold work. Here is a picture of the machine a few weeks ago while cutting a large aluminum part for another project:

The current cost of the machine is $663.75, that includes all components bought for the machine regardless of whether or not they were used and shipping. So far I've spent another $150.55 on endmill of various sizes for for cutting various materials.

Projects Past: The 2009 Automatic Cat Feeder

noreply@blogger.com (Will Winder) — Sat, 26 Jan 2013 16:27:00 +0000

In 2009 I took a week off from work to build an Automatic Cat Feeder to ration food to the overweight household cat. This was a project built from need and it had a deadline because my girlfriend and I were heading out of town for Thanksgiving.

The requirements were simple: It needed to be easy to refill and dispense the correct amount of food twice daily. Early on I had an idea for a large rotating drum to dispense the food, it needed to be easily removable for refilling and heavy enough that it could sit on a motorized wheel and cause enough friction to be turned.

Figuring out a latch mechanism that dropped the correct quantity of food after one rotation was the first tricky part. I didn't want any electronics on the drum so it had to be completely mechanical. In the end I hot glued a small box to the outside of the drum which filled during rotation, when it started moving back towards the top a tab would be hit to fling a door open and drop the food out. A magnet held the door shut and gravity would shut the door when the box made it back to the top. I'm extremely proud of this mechanism and it worked perfectly.

The dispenser mechanism! A marvel of engineering, hot glue, magnets and JB Quick Weld.

With all the details figured out, hacking it together turned out to be pretty easy. The hardware store patiently cut a sheet of 1/4" MDF into pieces for me which formed the box, and I was able to glue the pieces together with gorilla glue. A small stepper motor and some electronics were harvested from a 5 1/4" floppy drive and I was able to control it with an arduino. The program couldn't have been more than 50 lines, I figured out how many steps it took for 1 revolution of the drum through trial and error. Then coded it to do that every 12 hours.

The finished product. Seriously, we used it looking like this for several years.

The happy customer. My wife added a chute made from a mountain dew bottle.

I did make a couple upgrades after these shots were taken. The stepper motor died so I upgraded to sparkfun's cheapest stepper and an EasyDriver stepper driver. I also added a reed switch to the box and put a magnet on the drum so that I didn't have to count steps, this was needed because depending on how much food was in the drum it would sometimes slip and require a different number of steps to get back to the top.

Projects Past: The 2007 DIY Projector

noreply@blogger.com (Will Winder) — Sat, 26 Jan 2013 15:52:00 +0000

I've had many projects over the years, the most involved by far has got to be my DIY projector. It is also my first serious project. By the end of it I had vastly improved my knowledge of optics, electronics, woodworking, and even a little thermal dynamics.

Research started sometime mid 2007, the now defunct lumenlab forums had a whole community of people building DIY projectors. There is a lot of theory to learn, optics to figure out, components to buy, and bringing all the pieces together is no simple task. For such a complexe machine, at the core it has some very simple principles: A point light source radiates light into a fresnel lens, which straightens the light through the LCD screen, then another fresnel lens angles the light into a special lens which can focus the light on a screen. Here is an image from engadget which demonstrates the light path:

The major problem with these sorts of projectors is that they tended to be very large. 1080p monitors at the time tended to be at least 19" diagonal, which meant the entire box would need to be 3-4 feet long! Fortunately there were a few entrepreneurial types who started sourcing LCD screens that were smaller and ideal for DIY projection and selling them directly from the manufacturers. I managed to get my hands on one such monitor that was only 10.6" and had 720p resolution. With the LCD picked out I was able to begin designing the enclosure around December 2007.

Other than the LCD, the most important component is the light source. Some of the brightest bulbs consumed 400 watts of electricity or more, and had very impressive results. But with such high powered bulbs came a lot of heat that needed to be dealt with. I ended up going with a smaller 150 watt bulb.

The final pieces were the fresnel lenses and the projection lens. These were a fairly standard item and lumenlab took a lot of the guess work out of things by selling them from their store.

My final design to incorporate all these parts was a two chamber design. The top chamber had the optics. The bottom chamber contained all of the electronics: The LCD controller, the light bulb components (transformer and starting capacitor), and AC adapters and a heat sensitive trigger which would keep the fans running until the heat in the box dropped far enough.

The enclosure was designed to be simple to build and easy to assemble. The parts were cut on my dads table saw, and pieces were laminated together so that components could slide in and out of the enclosure during assembly. This design worked nicely.

In this picture you can see all the electronics (minus the thermal switch) and the various slots for the LCD, fresnel lenses, and chamber separators.

The LCD and Fresnel Lenses were built into frames that could easily slide into the slots:

The LCD frame had special protection for the delicate flexible cables of the monitor electronics. The frames for the fresnel lenses were similar.

The light source needs to be precisely positioned for the light to focus properly, so this box was built with rare earth magnets on the bottom. It attaches to a metal plate in the box which can be seen in the upper left of this photo.

The back was hinged so that adjustments could be made as needed, here you can also see the light box in place.

The triplet lens is another clever mechanism I came up with, by building the box a little loose I was able to pad it with felt so that the lens carriage could slide in/out but still be held snugly in place. The slot at the bottom was for a holding screw, but ended up being unnecessary.

Fully assembled, on the left is a front surface mirror which allows the box to be 11" deep instead of nearly 30.

The final result is big and ugly, but it worked and I used it for years. I'll never forget how surprised my girlfriend was when I plugged it in for the first time and an image, apparently she thought I was crazy for those 5 months. In the end it really did work nicely. Designing it was a lot of fun, but my craftsmanship really limited my options.

More pictures can be found on my flickr page: DIY video projector

XCode4: UITabBarController with UINavigationController using Interface Builder

noreply@blogger.com (Will Winder) — Thu, 19 May 2011 12:34:00 +0000

If this helped you, please consider downloading my FREE iPhone app "Hydrate Yourself"and leaving a review.

There are a whole bunch of tutorials to create a Navigation Controller inside a TabBarController with XCode3. But there are a number of small changes in XCode4 which can trip up someone not familiar with them. So this guide is essentially an updated version of those other guides, designed to create the same simple demo using the new tool.

1. Create a new Project
We are going to start with a Tab Bar Application, so go ahead and create a new project as usual. I'm calling mine Navigation Tab Bar.

2. Select the Tab Bar
Click MainWindow.xib and you should see the integrated Interface Builder. On the left is a section called Objects, select the Tab Bar Controller.

3. Add the Navigation Controller
On the right side of your screen click the Utilities box. This is new in XCode4 and should look familiar if you've been using XCode3. At the bottom find the Navigation Controller and drag it into the Tab Bar in the middle of your screen.

Here you can see I added it as the middle Tab

4. Configure new tab

Back in the Objects section you can now expand the Navigation Controller and select the View Controller object. Now on the right side you can select the Identity Inspector at the top and put in your UIViewController's class name. For the purpose of this demo I am calling it "YourNewViewController" which we will make at the end.

Once that is done switch to the Attribute Inspector and put in the name of your XIB file in the NIB Name section. Note: do not add the .xib extension, this will cause a runtime crash.

5. Create the new UI View Controller

This is probably familiar to you already, create file from the File menu and select a UIViewController subclass.

Be sure to select With XIB for user interface

Use the same file name as you used before.

6. Add an IBAction

We will be adding a button to push a view onto the navigation controller. Open up the header file and add an action.

I just added the buttonPushView line

Switch to the implementation file and add another few lines for a simple call to pushViewController.

This is the simplest pushViewController line I could come up with

7. Add a button

Select YourNewViewController.xib in the file menu. Adding a button is a simple matter of dragging/dropping from the bottom right Objects section.

Next you link the button to the new IBAction by right clicking the button and dragging the arrow to File's Owner, in the Placeholders section. Select buttonPushView.

8. You're done!

All thats left now is the build and run (Command-R). Select the second tab to see your new Navigation Controller and click the button to see it in action.

Vim Search for Tags File

noreply@blogger.com (Will Winder) — Tue, 05 Apr 2011 15:00:00 +0000

I use ctags with vim. This works great when the tags file is in the same directory as the files I'm working on, but is a chore when projects have nested directories.

Add this to your .vimrc file and the recursive search up the directory structure will be done for the tags file:

set tags=tags;/

Why Hydrate Yourself?

noreply@blogger.com (Will Winder) — Sat, 08 Jan 2011 01:57:00 +0000

This is a short essay about why I decided to create "Hydrate Yourself". It is a free app for the iPhone, iPod touch and iPod which tracks water intake and helps encourage a healthier lifestyle.

According to webmd.com [1] and the US National Library of Medicine [2], symptoms of dehydration include: Dizziness, Lethargy, Lightheadedness, Headaches, Fainting, Weakness and (naturally) a Dry mouth. Other symptoms even include heart palpitations (that feeling of your heart jumping or pounding).

So why is it that water intake is such a secondary concern to so many adults? All it takes is a little attention throughout the day, such as keeping track of how much water you are drinking or carrying a water bottle with you at all times. I strongly believe that drinking enough water is one of the easiest ways to improve your health. But how much water is enough?

Its hard to say, since so many foods we eat every day contain water. Common "rules of thumb" include 8-10 glasses a day, or your body weight divided by two. In reality it will always vary from person to person depending on their lifestyle. For example if you drink a lot of diuretics, like coffee or caffeinated sodas, you will retain some of that water but not all, which skews how much you need to drink. Another factor is your personal activity levels, anything which causes you to sweat causes you to lose more water which needs to be replenished.

One of the most accurate litmus tests for determining whether you should drink more water or not is the color of your urine [3]. The web page urinecolors.com has a color chart stating that if your urine is light orange or darker that you need to drink water immediately.

With all of that known it is easy to see why you should make an effort drink enough water. I spent the last three months of 2010 creating a program to help with just that. After being unsatisfied with the alternative water tracking applications I designed "Hydrate Yourself" from the ground up. There were three key features that needed to be done right: Easy to use multiple containers, multiple calculators for recommended intake, reminders throughout the day to drink more water.

I added two daily intake calculators and an option to enter a custom amount. These calculations can then be used or customized to fit your ideal intake amount. There is a simple calculator that is based off just your weight and basic activity levels (low or high), then there is a complex calculator which is based on your weight, daily minutes of activity, climate, illnesses and more. Of course you can also skip all that and enter a direct amount - maybe your doctor made a recommendation.

A problem with the alternatives is that it can be difficult to use multiple containers, or modify them on the fly. Taking this into account I added a configurable spot on the main page for three containers (such as a water bottle, your favorite glass, and a drinking fountain). From there you can just tap the icon and have it logged or press and hold to get extra options - add a partial serving (half a water bottle), change the default portion size (a new waterbottle holds 32oz instead of 20oz) or add a serving that you forgot to enter earlier (I often forget to add my first glass in the morning).

Perhaps the most useful feature is the ability to add customizable reminders. The hardest part about drinking water throughout the day is remembering to drink it at all. To help with that I added a reminder. It goes off a customizable amount of time after you add a portion, or finish using the app. If it goes off I know that its time to get myself some more water.

[1] http://www.webmd.com/a-to-z-guides/dehydration-adults
[2] http://www.nlm.nih.gov/medlineplus/ency/article/000982.htm
[3] http://www.urinecolors.com/dehydration.php

Fetching a large data set with Core-Data

noreply@blogger.com (Will Winder) — Thu, 02 Dec 2010 23:32:00 +0000

I needed loop over a potentially large set of data stored in Core Data, but did not want to force the system to load the entire data set in memory or have Core Data constantly process faults. There seem to be several ways to do this, some easier than others. One robust way would be to use an NSFetchedResultController, but it looked a little more complex than I wanted to deal with ( and involves implementing yet another protocol).

After poking around the NSFetchResult class page for a while I noticed these methods: setFetchLimit and setFetchOffset. It turns out that these are just like the LIMIT and OFFSET keywords in SQL, which is just what I was looking for.

Using this method is just a few extra lines of code. This is what it looks like:

Custom UISwitch to show YES / NO

noreply@blogger.com (Will Winder) — Thu, 18 Nov 2010 14:28:00 +0000

You can see this in action in my free water tracking application "Hydrate Yourself". If this helped you please consider downloading it and leaving a review.

One of the great things about iPhone development are that there are lots of user interface pieces that are easy to put together and customize. Unfortunately there are also a lot of pieces which don't have all the basic customizations that may people want. The UISwitch is one of those.

Here is the standard UISwitch:

Its size, colors, and ON / OFF text are not changeable. Fortunately there are several great re-implementations (and a few hacks that use restricted API calls) to modify all this. One that I am using is the RCSwitch class available here.

I made two small changes to this code, first I renamed his RCSwitchOnOff class to RCSwitchYesNo and changed the labels to YES / NO. Second I added an init method to the RCSwitch.m base class which called the usual init function but provided the default frame size. This works fine since I am positioning the x and y coordinates using the "center" property:

The final result looks and behaves just like the original UISwitch, but is actually completely rewritten using the UIControl class. My switches now look like this:

UITableView which is its own Delegate and DataSource

noreply@blogger.com (Will Winder) — Sat, 09 Oct 2010 03:54:00 +0000

I spent some time tonight working out a simple class which extends UITableView and conforms to its own protocols. If you are just learning about UITableViews they can seem a little daunting, but like so many other pieces in the iPhone toolbox they are very easy to use once you get the hang of it.

If you add a UITableView to your root view it will be a box with some lines across it and you can make them move by touching and dragging in vertical gestures. In order to respond to the touch selections you must set a delegate to the class, just like any other object (Like UIButton or UISwitch). There is a second delegate called "dataSource" which is used to populate the table "cells". The delegate class must conform to UITableViewDelegate and UITableViewDataSource.

Taking Stuff Apart: Coffee Machines

noreply@blogger.com (Will Winder) — Sat, 03 Jul 2010 21:22:00 +0000

These are some broken coffee machines I've had hanging around for a while. The cheapest Mr. Coffee that Walmart sells and some fancy Morphy Richards coffee/espresso machine. The fancy one was from my first and only Woot Bag of Crap - they sent me a broken coffee machine.

Rather than throw them in the dumpster I decided to take them apart then throw them in the dumpster. Here they are:

Not much too Mr. Coffee:

The pieces slid out and that was all there is to it:

There's a lot to the other one:

Most of the pieces clip in so it took some brute force to pull them apart:

Some electronics for the front panel:

The power circuitry was all hidden around back:

Pieces! I kept the heating elements from this one, maybe I'll make a little mug warmer or solder reflow table someday:

This Way Up: First App Submitted

noreply@blogger.com (Will Winder) — Wed, 30 Jun 2010 03:22:00 +0000

Free Version and Ad Free Version

I've submitted my first app to the app store. The process was fairly easy. Hopefully a couple people will find it and be amused. At 99c this app which uses the magical iphone accelerometer is certainly a bargain.

Here is a video:

Make a TAP with a MAC in Garage Band

noreply@blogger.com (Will Winder) — Wed, 09 Jun 2010 01:40:00 +0000

I'm not a very fun person, so using a fun computer like a MAC is hard for me. Using fun software like Garage Band is even harder. I needed a TAP sound for a project I'm working on and this MAC is the only device I have with a microphone, and Garage Band the only program I knew of for doing audio stuff.

This is the guide I wish I had earlier today.

1. Create a new Voice project:

2. Click record:

3. Tap like crazy. I used the Shift key, there are several other available keys you could use instead:

4. Tap Tap Tap:

5. Double click up top to get the bottom details. Play back to find your favorite segment.

6. Click the loopy arrow at the bottom, shorten the yellow bar at the top to shorten the track:

7. Select export song to disk:

8. Choose your quality:

The results speak for themselves:
http://willwinder.com/sound/tap.mp3

This tap sound is free to use for any purposes if you leave a comment below saying thanks!

iPhone App: This Way Up

noreply@blogger.com (Will Winder) — Wed, 02 Jun 2010 22:31:00 +0000

I started working on a new project the other night. It took most of the night but the proof of concept looks promising. Take a look at the video below, follow the link to flickr to see it in HD.

Taking Stuff Apart: Sony TC-800B Portable Reel-to-Reel Recorder

noreply@blogger.com (Will Winder) — Tue, 01 Jun 2010 03:07:00 +0000

Today we have a Sony TC-800B to take apart. This is a portable Reel-to-Reel recorder is from the late 60's or very early 70's and is the same device that was used to record the watergate tapes. Unlike the TEAC 360S I took apart last week, this machine was very easy to take apart.

The one I came across even had a carrying case, you might notice that the handle is crooked. This thing was somewhat busted up, if you look closely you can see through the window in the case that the plastic covering the reels is cracked too:

The reels:

Glamour shot:

There were just 4 or 5 screws to take off to expose the mechanical guts. Here you can see the pulley from a large motor to the right reel, and another pulley from the left reel to a counter. Also note the trench at the top where all the wires are nicely fed through. At this point there were just a couple more screws holding the whole assembly out of the case:

If you click this picture and look at the original photo you can see that there are 3 bars stacked ontop of each other. These were directly attached to the Play, Stop and Fast Forward buttons. The rewind button reset them:

The pieces came off without much fuss:

Taking it out of the plastic housing and flipping it over reveals the electronics half. I especially like how the PCB curves around the motor:

I noticed that the 'O' in SONY on the PCB was raised in a strange way:

These came off easily, notice the switch in the bottom left:

I got it:

And here is the rest of the harvest:

Card Catalog to Parts Storage

noreply@blogger.com (Will Winder) — Mon, 24 May 2010 00:24:00 +0000

Sometime last year I started kicking myself for missing the mass exodus of the card catalog. I came to the obvious realization that these giant dressers full of small drawers would be perfect for storing small tools and parts. Not only do they have a nice size but they're built like tanks, they're meant to be opened and closed all day long after all.

Well I finally have one, and it has been converted ever so slightly to be usable for storage.

It is on the small side, with only six drawers:

All that was really needed was to cut some rectangles from a sheet of hardboard and tack them in place with hot glue:

I can't complain about the results though, I still need to make new labels though:

Taking Stuff Apart: TEAC 360S Cassette Deck

noreply@blogger.com (Will Winder) — Sun, 23 May 2010 23:57:00 +0000

Usually I treat taking something apart like a puzzle. It is strangely satisfying to have something come apart nicely without resorting to brute force and wire cutters.

This cassette deck didn't provide that satisfaction. It got to the point where I was taking out every screw I could find hoping something would budge. To make matters worse it was greased up in places so by the end it looked like I may have been working on a car instead of taking apart a piece of consumer electronics.

The reward were some swanky dB meters and a pile of switches, so it was certainly worth it.

As you can see, this was scrap so there was no guilt when it came to gutting it:

It had one of those wood sidings that I like so much at one point, but not by the time it got to me:

The bottom came off easy enough:

The top also:

This "caution" plate on the back seemed out of place and had a useless warning. Turns out it was just used to hide some extra ports which I suppose came in a deluxe model:

There were pulleys running all over the place for displaying some sort of counter:

Here are the pulleys continuing on the bottom (they hook up with the picture above on the right side of the picture below):

This is the point I started getting desperate, this thing just wouldn't come apart and I started trying to pull off pieces which were still attached to other pieces:

After cracking it open I noticed this little reed switch. I was very happy to see one of these in there, they're apparently fairly uncommon since I hadn't seen one in anything else I've taken apart:

More trying to dig things out:

Pulled out a large motor:

These cassette deck mechanisms are always interesting to look at. You can see the timer pulley fully visible at this point:

There were a bunch of springs, I gave up trying to figure out how they worked:

The guts, it took some serious wire cutting to get them apart. This thing was a tangled mess, it's hard to imagine how long it would have taken to assemble one by hand:

Jackpot, here are all the switches and slide pots:

Not a bad haul. Here is the after shot, in addition to the switches and slide pots, there were a bunch of tiny bump switches that were scattered along the cassette mechanism, a solenoid, the reed switch, and some aluminum plates:

Taking Stuff Apart: LCD Screen + Digitizer

noreply@blogger.com (Will Winder) — Sun, 23 May 2010 19:02:00 +0000

Occasionally while tossing a scrap into the discard pile it occurs to me that the scrap is composed of multiple pieces, and that I could throw multiple scraps into the discard pile instead of just one.

That is what happened while I was throwing the broken LCD Screen + Digitizer from my GPS Screen Replacement project. From the get go this was obviously a bad idea, evident by the shattered glass. I've also taken LCDs apart in the past and know that the only piece of real interest is the polarized sheets glued to the glass, those sheets are a pain to get off so that wouldn't even be fun.

Regardless I opened it up and have slivers of glass stuck in my arm some sort of badge of honor:

I skipped a few steps here. The bottom left piece is the actual LCD glass, the bottom right is the metal backing, the top right is the front glass and the top left is the backlight + reflective sheet + diffusive sheets which went between the metal backing and the LCD glass:

An exaustive post-mortem analysis of the device suggest that the malfunction had something to do with this piece:

Pulling these sheets off was miserable, but I did it. I couldn't get a good shot of the polarization sheets though:

I found these little LEDs as the backlighting, I thought it was pretty neat:

Taking Stuff Apart: Panasonic RC-6005B

noreply@blogger.com (Will Winder) — Sun, 23 May 2010 17:13:00 +0000

When I came across this clock the first thing I noticed was that it was branded an "AM-FM DIGITAL CLOCK". This wouldn't be unusual except that there wasn't a single digital component in site, not even an LED. This is a classic "flip" clock with impressive mechanical properties that we would barely consider digital today. Not only that, but twisting the various knobs provide satisfying mechanical clunks and ticks! The thing makes a lot of noise though, so it wasn't approved for use as my nightstand clock.

The internal components of this are very similar to the clock used in the movie "Groundhog Day". Thanks to this clip I can say the actual flip mechanism is probably identical.

Here it is, in all its digital glory. Take note of the bug lodged behind the plastic - this beautiful device is dirty:

I knew this was going to have some great mechanisms in it before starting, but what I didn't know was that these three screws were going to be the only thing holding it together. EVERYTHING inside was on rails and were held in place by the various knobs connected to the components. Amazing.

Here it is after the back was opened, notice the rail holding the PCB in place on the left and the black tube which holds the hole thing in place with the volume knob. You can also see a nice array of gears used to display what station is currently being tuned:

On the opposite side you can see this strange gear (actually two gears, one has a hole in it that the other fits through) which controls the alarm settings (on/off/recurring/etc) and how long the snooze lasts, between 1-60 minutes:

Everything slid out:

The flip mechanism, notice the little black tab holding the hour in place so that it releases exactly as the minutes turn to 00:

I expect this is what causes all the noise, I wonder if this is also used to keep the time:

I wanted to use this as my nightstand clock, so all the dirty pieces took a bath for a few hours, which worked fairly well but needed some additional scrubbing for all the little ridges:

Taking Stuff Apart: Panasonic WV-200 Video Camera

noreply@blogger.com (Will Winder) — Tue, 18 May 2010 23:52:00 +0000

I couldn't find any references to this camera aside from the tube - a 20PE13A which has a few ebay auctions for $50-$70 right now. If anyone knows anything about its history I'd be curious to hear it.

Since I don't know anything about it, here it is:

Bottom / Mounting bracket:

Front / Lens. I'm not sure if there was some sort of optics that someone else took or not:

The bottom came right off after a few screws, hey there's some sort of tube in there!

The rest came right off after a few more screws:

There were two PCBs with the components sandwiched in the center:

They came right off too:

This thing is apparently some sort of photo sensor:

Nothing in the big metal cylinder actually touches the tube:

After cracking open the transformer, all evidence suggests that its ancient:

All done, not much to salvage out of this thing unfortunately:

As usual you can find more pictures on my flickr page by clicking on any of the images above. If you have any information about how that tube works I'd be curious to hear it.

Nuvi 760 Screen Replacement

noreply@blogger.com (Will Winder) — Sun, 16 May 2010 17:55:00 +0000

This is how I replaced the LCD in a fairly new Garmin GPS device. The thing is not designed to be consumer serviced so it was a huge pain - likewise I couldn't find any information from other people who have been through the ordeal. Everything begins on ebay, where there were several vendors selling replacement LCD's. Be sure to get an LCD + Digitizer combination, it is likely to cost somewhere between $30 and $60.

Here is the damage:

I was happy with the replacement kit - it came complete with some special screwdrivers. Specifically a very small philips screwdriver (which was actually too small) and a star shaped one that was needed to even start.

The first step is to crack the front open. This is not for the faint of heart and will take significant force and prying. There are tools for this type of thing but I used a sharpened flathead screwdriver. Expect to break a couple of the tabs. There are some cables that go between the two halves but you shouldn't need to worry about them.

Here are the cables you need to remove, they're slotted so you don't need to worry about putting them back in the wrong way:

This PCB is attached to the LCD with a flexible cable so remove it carefully. I found that prying here dislodged it at which point it could be gently removed. The audio port and a little tab in the lower left are primarily what holds it in place.

Make a note of how this one is oriented, tweezers will help getting it back into place:

Almost there, just need to remove this plastic middle piece:

More prying is required, expect more damage to be done:

At this point I found out that the seller had sent me the wrong part. Note: It was the part he said he was selling, but Garmin changed what LCD is used. Fortunately he was able to source the part I needed and swapped it out with no questions asked - Just had to wait a few weeks for the round trip shipping back to Hong Kong, which turns out to be less than $3 for a small box. About a month later and I'm back in business:

Just a matter of putting everything back together now. The biggest issue is getting the flex cable seated correctly, you will need to have the LCD removed from the frame and the flex cable completely extended. Make sure its seated squarely, I had to take the whole thing apart a second time thanks to this mistake!

Getting the frame on is also a puzzle, you can feed the PCB through like this. Be sure to get the red and black cable plugged in when seating the PCB.

You're basically done now, just snap everything back together and plug it in!

Portable TV Music Visualizer

noreply@blogger.com (Will Winder) — Mon, 19 Apr 2010 17:53:00 +0000

A while back I took apart a Magnavox BH3908 portable TV and promptly turned it into some sort of DIY Oscilloscope. Well another fun thing to do with these things is to hook it up to your stereo and get a music visualizer. Take a look at the video to see what I mean.

BarCamp Boston 5 - Day 2

noreply@blogger.com (Will Winder) — Mon, 19 Apr 2010 14:51:00 +0000

There were some more great presentations at Barcamp Boston 5 day 2, here are some comments on the ones I went to.

Your Website Sicks! But it can be saved
This was a great presentation, he showed a lot of examples showing how things can go wrong when the balance between form and function are skewed. One example he gave was the geeksquad website, which has lots of information but doesn't have an easy way to get an overview of what they do. After the presentation a few people volunteered their websites for critique. He had a lot of great feedback for them including "You have a FAQ section, has anyone ever asked these questions?" - which got a good laugh. There was only time for two, so I didn't have a chance to volunteer this site.

He referenced smashingmagazine.com as a good source of design info.

Agile Programming Methods
This was sort of a crash course on Agile but had some nice group discussion on what tools people are using, and on what parts of Agile methodologies are really important. For continuous integration a few people were using Hudson, he mentioned Cruise Control; no one else was using Electric Commander though. Not many people using pair programming, it will be interesting to see if that ever really picks up.

When Will Immersive 3D Web Arrive? And: What you will need to do to get ready: Maria Korolov, hypergridbusiness.com
This lady was either crazy or a visionary, either way I didn't realize 3D social environments like SecondLife were getting so big. She had a whole bunch of predictions about where this technology will be in 5, 10 and 15 years.

There were some fun-facts thrown in there too, for example, some companies use this technology and enact dress codes on the virtual characters; Some platforms like SecondLife require you to use a fantasy name rather than your real name so imagine executives with names like "Star Catcher".

She also used the early adoption curve showing that this technology was still before "The Chasm".

Rule Based Programming in Interactive Fiction; Or, How I learned to stop worrying and love them declarative languages
This was a neat view on a very specific programming problem: How to design text based adventure games. It wasn't what I was expecting at all, but was a good peek into an area that I knew nothing about. He started off by describing some pitfalls to a simple Object Oriented approach, his design got bogged down by edge cases and special conditions. He finished up by talking about a prolog-esque rule based language (I'm not sure if it exists or not) where you create many rules to describe the objects and rooms and let the language crunch all the rules for a given action and give you a result. At one point he mentioned "You need a language built from the ground up which is designed to hack itself".

Don't Be a Douche - Best Practices for Game Mechanics in Your Webb App: Sachin Agarwal
This was probably the most entertaining presentation of the day, he started out using a Wii controller to advance slides and made some wrestling characters represent people in a business. A lot of his presentation was inspired by this presentation "Design Outside the Box", you should check out his blog for more.

There were some amusing quotes that stuck out:
When describing badges / achievements "evil evil awesome shit"
"Does the house win in the app your making? It should..." response to a question mentioning online poker.
After mentioning Emoticons / Emoji are popular with Japanese girls: "You know that when shits big in Japan that its gonna come here eventually"

Version Controller Discussion: Shankar
This was a round table discussion about what people are doing with version control. Most of the group were using free centralized / distributed solutions. A handful were using commercial things like clearcase/perforce/accurev. Noone used something valled Versioning Filesystem or Visual SourceSafe. A couple funny things people mentioned was having a lava lamp automatically switched on when someone breaks the build, and having a "break the build" jar where you put some money in if you broke the build.

Closing
The event wrapped up with the programming contest winners and some feedback from the audience on the event. If you have feedback update the wiki at wiki.barcampboston.org.

BarCamp Boston 5 - Day 1

noreply@blogger.com (Will Winder) — Sun, 18 Apr 2010 00:10:00 +0000

Barcamp was a lot of fun, tons of interesting talks and learned a lot too. Here are some notes and reflections from the ones I attended. Unfortunately I hardly got any of the presenters names.

Hacking the Brain
This was really neat, the guy has a way to turn neurons on and off using light. He has a small worm with about 300 neurons that he tracks with a camera and shines light on to see what the different neurons do. Interesting discussion at the end about the technical limitations he's hitting regarding latency between taking a picture of the worm and being able to calculate where to shine a light.

User Experience Design for Developers
This guy (Dennis, I think) really seemed to know is stuff. He had some interesting ideas on how to design successful software and some insights that really made the points stick. Here are the notes I took:
*The end user is the worst person to ask "What do you need it to do?"
*Develop for a specific persona, be very specific.
-Jane Doe, drives a 3 year old civic because she likes value.
-Apples persona is Steve Jobs, part of their success is having a very targeted persona
-This also helps with feature creep because you can ask "Does the persona need this?"
*Describe how the software works, ensure stakeholders agree
*Create very non-visual wireframes to demonstrate the UI. "Not a prototype"
*Ask the same question 3-4 times in different ways.

openFrameworks: C++ for artists & designers : Theo Watson
This was all about a really neat framework for artists. The technical part was extremely brief so that he could get right into showing a bunch of videos of projects people have made. Probably the most surprising part was that I had already seen / heard of many of the projects he talked about! Here's a link with some videos: http://fffff.at/author/theo/

3D Printing & MakerBot/RepRap Demo
I've been a fan of the RepRap 3D printer for a long time, and the MakerBot this guy had was even cooler; Complete with blue LED's. He went through the process of how to load up a 3D model someone else made into the printer and kicked it off. Unfortunately the session ended before it finished printing!

Quick & Dirty Usability Testing: Christine M. Perfetti
This had an interesting contrast to the other usability talk. The morning one seemed geared towards making sure the software is usable to begin with and making sure the design will work, while this one was based on how to get reactions from people to find out if the design did work.

Here are the notes I took:
*Just watch the user use it
*Don't use high-tech usability labs (makes the person uncomfortable and they know they're being watched anyway)
*Bring user in, introduce the observers (first name), sit by them, watch what they do
-greet
-explain test
-give them task, observe problems
-general Q&A (How was the Experience? What was good? Bad?)
-Debrief with observers
*5 second page test
-simple, can take less than 10 minutes, can use mock ups, tells a designer if the page is clear
*Paper Prototype #1 way to start testing
-draw the screen
-user points at drawing
-person swaps paper based on what the software will eventually do
*Comprehension Test
-sort of like SAT comprehension test

Mobile Apps & Analytics
This was almost like google analytics except for mobile devices. There is a special storage component so that 100% internet connectivity isn't required. Check out http://www.localytics.com/ there is a free version of their service.

Connecting the world of cooking with Plummelo.com
Plummelo.com looks like a really cool site, I really like the allrecipies.com iPhone app though. It sounds like its getting better every week so I'll have to give it a shot.

Game programming in Ruby
Given by the same guy as plummelo.com. There were some technical difficulties so he couldn't show off the stuff he was doing. It sounded like he was using Ruby to make some sort of MMO, which sounds like crazy talk. It was also web based though so maybe the server isn't doing much?