I was fortunate enough to have a piece of genuine Plexiglas brand acrylic from which to forge the coilform. Since Roam & Haas got out of the Plexiglas business in the 90’s, I don’t think you can get such acrylic sheets under that name any longer. Sure Lexan is harder, but Plexi is really easy to work with. If you want some Lexan, buy a Nalgene bottle. Using acrylic for the coilform even more strongly forces me not to use cyanoacrylate to bond the coils together. I must keep looking for an appropriate adhesive.

Here are the pics. I used a precision hole depth gauge to measure the thickness of the pieces because I don’t have a good precision (or well any) caliper.

I need some good glue, and an appropriate applicator to do the layers of the coil. I’d like something similar to the tiny applicator I used to have for model-train oil. It was like, a squeeze bottle with a long thin metal tube. Maybe a brush on thing would work too. Also I need to buy the bolts I will hold this together with, as well as the whole galvanometer frame.

Sunday night I dined at the Pick Me Up Café. I enjoyed the meal;

PJ Chmiel has some good pictures of a sampling of the food you can get there. (I just googled for a link…)

I really don’t go to the City enough. Maybe I’ll do that some more while I am home. Anybody up for a visit?

*EDIT*
I forgot to mention how excited I am about a possible 2 to 4 inches of snow overnight! (on the first night of spring???)

I have spent the past two days, since my large spool of magnet wire got here, making a 120 turn really nice coil.It is the nicest coil I’ve ever constructed. Unfortunately that isn’t saying tooo much… I took pictures of it, but the jig I used was destroyed in removing the coil–and I forgot to take a picture. Anyway, it was difficult to make, and I used a lot of superglue. This was bad for a couple of reasons; 1.) Superglue fumes are bad. 2.) it enlarged the dimensions of the coil beyond a reasonable margin of error, causing it to hit the axel on the prototype galvo frame. Fortunately this was just a prototype, so I had the opportunity to learn. One of the main problems was it turning out too thick, requiring me to cut a divot in to the galvanometer frame so that the axle would fit in. Second, it didn’t seem as if i was being very efficient in winding, nor could I be consistent with all that messy glue and putting each turn on and pushing it in to place with a screwdriver as the super-glue set. Now, discussion on how I think the winding pattern can be improved.

The current 120 turn winding pattern was this:
I plan on replacing it with a 124 turn coil, of different dimensions like this:

OLD:                      NEW:
0000000000       0 0 0 0 0 0 0
                  0 0 0 0 0 0
0000000000       0 0 0 0 0 0 0
                  0 0 0 0 0 0
0000000000       0 0 0 0 0 0 0
                  0 0 0 0 0 0
0000000000       0 0 0 0 0 0 0
                  0 0 0 0 0 0
0000000000       0 0 0 0 0 0 0
                  0 0 0 0 0 0
0000000000       0 0 0 0 0 0 0
                  0 0 0 0 0 0
0000000000       0 0 0 0 0 0 0
                  0 0 0 0 0 0
0000000000       0 0 0 0 0 0 0
                  0 0 0 0 0 0
0000000000       0 0 0 0 0 0 0
                  0 0 0 0 0 0
0000000000       0 0 0 0 0 0 0

0000000000

0000000000

Silly ASCII art was limiting here–these are actually wider than taller, but you get the picture. The interleaved pattern of 10-9-10-9-etc will make sure it does not exceed the height requirement, as I believe the first one did after slipping in to an offset pattern.

For this coil i used a jig made simply of a piece of basswood cut to the required inside dimensions, and glued it to another base piece, and wrapped the coil around it. It was especially hard at the top of the coil. For the next coils, i have an idea for a jig made of plexiglass and aluminum, that will use an aluminum core, and plexiglass top and bottom–bolted together. This will allow me to use far less glue to hold the coil together during construction, and hard limiting its thickness.

I’m also going to need some better glue– i’m thinking a rubbery kind? not sure yet– hopefully one that gives off less fumes.

I estimate it takes maybe 35 feet of wire to make a single coil. I estimate I have maybe 1 mile of 28awg magnet wire. This means, I should not be in danger of running out due to making this, or the next, practice coil.

P.S. The whole thing turned out to be like slightly less than 2Ω.

At an unspecified time sometime likely Monday my vehicle experienced a delamination failure in plastic-plastic bond pictured below. The automobile component previous replaced in November 2001 was possibly exposed to high winds that day and temperature fluxuations of typical of winter. Fortunately an anonymous citizen returned the debris to a secure location for investigation. It does not appear as if any foul play was involved, as occurred in the previous incident regarding trunk mounted counterpart to this item in 2002.

The failed component is scheduled for replacement when I return home the week of the 19th.

Photo documentation:

So last year I worked really hard on LaserLine, with the gracious help of MacWarriors . It turned out pretty well, but there is still much to do. The largest problems were: first, the lack of quality hardware, and second, the lack of documentation for building said hardware. Thus far, the output hardware has been the classic speaker-scanner design, driven by a high-power op-amp.The two speaker design, while functional, was not really capable of reproducing the output we could generate with LaserLine.

Furthermore, I’d really like to even more advanced vector based output using a hardware device like the bILDA interface from linux-laser.org.

I am walking in the footsteps of ChaN with his ELM projector, and Norm with his. I hope to combine their successes with my own philosophy to create a high-performance easy-to-use laser projection system.

So the most difficult part is, in the words of Mr. ChaN, “to build the laser projector with professional grade :-).” Hopefully I will succeeded with this goal, for I have the utmost respect for both of these Laserists and there amazing work before me. I would not be able to undertake this project without their work.

I have CAD drawings ready for the Galvos themselves, and all the parts on the way including 28awg wire, .01″ thick Copper clad board, and the appropriate cylindrical magnets. I have built a working wooden prototype, but there are a few items, such as the coils, which are completely different from the final version. There is also no Position Detector in the prototype.

Whole Album

I have created a new category for posts related to this construction as I anticipate development will require much posting. I will also be creating a project page soon.

Design Specs include:

• Galvo design based off of ELM design, but out of machined aluminum for better heat dissipation and precision (I don’t trust I could cut circuit-boards so finely myself!)
• Amp based off of ELM design with additional Signal LEDs and Thermal protection circuit for coils on manufactured PCBs
• Capacitive Position Detector, driven by Norm’s Crystal-based circuit
• ILDA compatible input board for computer-teathered operation
• chemical-etched Position Detector pieces for finest control on dimensions of copper plates

I would love to hear anyones comments or suggestions. Thanks!

In addition to David winning 2nd place for RingCycle in Undergrad Research at EOH, a number of other great things happened. I saw a hawk the morning before EOH as I stayed up all night a Siebel, and I happened to get my great new Magnets in the mail from Engineered Concepts. Proof:

I strongly recommend checking it out. Even if only for a little bit, its amazing. This year I would like to recommend everybody go visit David Kaplan’s RingCycle exhibit, as its really awesome–and I made the posters. I also must recommend all of the ACM exhibits in the Siebel Center, including MacWarriors’ exhibit, because I am a member of that group.

I look forward to checking out exhibits in Everett as well, because they have cool electronical things in there always. Soon I will be building and blogging about electronical things–I will take photographs when the parts come in; it’s going to be big.

Also, there will probably also be Balloons. Yay Balloons.

*Edit*
EOH == Engineering Open House

I know my blog is not only for birthday announcements, but this is an important one:

Today is my mom’s birthday.

Happy Birthday Mom.

Expect some exciting posts about a Weather Adium Xtra soon…