Seeing as I’ll be doing a lot of prototyping, I figured it would be good to have my own rapid prototyper. So I’ve built a reprap, it’s almost finished. This is the ponoko model. Progress so far: 
Reprap
20 12 2008Comments : 2 Comments »
Categories : CAD, Fabrication, Rapid Prototyping, reprap
First Coil
11 12 2008
I ended up using ruby-serial to control embedded code in the Arduino. The problem with the wrong number of steps per revolution was from packet loss, by slowing down my ruby program the error went away. I need to get some more test wire to wind a full torus now!
Comments : 2 Comments »
Categories : coils, polywell, robots
Coil Winder
5 12 2008Here are the pieces for the coil winder, partially assembled.
you can see the grain of the rapid prototype:
Already I can tell the bobbin is not well supported axially. I doubt it will be able to keep tension with 12 gauge wire. But we can test thinner wire on this iteration.
Putting it together:
As expected, the axel needed reinforcement:
Doing some quick checks. The stepper motors are supposed to take exactly 400 steps to complete a revolution. However, when I program the bobbin to take 400 steps forward then 400 steps backward, it appears to come just short of a full revolution! WTF! It looks like it’s closer to 415 steps per revolution. But I can’t trust that number to be accurate over many revolutions.
I’m learning RAD, a gem for controlling the arduino from ruby. Very cool.
Comments : 2 Comments »
Categories : coils, Fabrication, polywell, Rapid Prototyping, robots
Rapid Prototyping
1 12 2008I’ve been researching various methods of rapid prototyping. So far I have used FDM to create the parts for the coil winder, including the bobbin. I’m leaning towards using SLA to fabricate the chassis itself. SLA offers the largest build envelope (20″ X 20″ X 20″), and new resins are strong and heat resistant.
Comments : 1 Comment »
Categories : Rapid Prototyping
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