Four Little Coils, Sitting in a Row
Thus far the most challenging part of building the laser galvanometers has been winding the coils. I felt it very important to wind the coils as densely as possible, and with each wire parallel, rather than randomly in a big lump. They almost look as if a machine wound them, though my fingers were the primary mechanism involved. Well, maybe a slightly defective machine, as they aren’t perfect, but pretty close for having no experience.
You can see the Coilform in a previous post, so I’ll get right in to the winding process I used to produce these coils.
First I prepared my workspace with the following items:
- Super-glue
- Aleene’s Tacky Glue
- Paintbrush
- Magnet Wire
- Coilform
- PostIt Note & Pencil
- Pepsi (or Caffeinated beverage of choice)
- Water
- Screwdriver
- X-Acto Knife
I proceeded to thread the magnet wire through the coilform and wound the extra on the screws protruding to the outside.
The process was pretty straight forward. I carefully wound the wire around the form, one turn at a time, pushing it in to place with a precision screwdriver. 9 turns on the first layer, 8 on each following. I’m not sure why, but I was just able to get one extra in on the first layer.
After each layer was complete, I applied a layer of tacky glue. This stuff is very similar to Elmer’s glue, but stickier. It was primarily used to hold the coil together while winding it, but likely will add some internal structure as it hardens. It seemed pretty messy, but cleaned up with water, so no permanent harm done. I used a small paintbrush to apply the thin layer of glue, cleaning the brush with water after each layer. It was also important to mark down progress on the PostIt in order to avoid loosing track of the number of layers. After a while they all start to look the same, and it was more difficult than I would have liked to look though the side of the coilform.
After the 113 turns it was ready to be removed from the form. First I tacked down the last wire with a little bit of super-glue, then removed the screws. The X-Acto was required to get the coil away from the sides of the coilform. I did not wait for the glue to dry, and instead relied on it’s tackyness– I am not sure if this was a good or bad idea, for it certainly worked, but may have gone more easily had I waited for it to dry. I was somewhat afraid the form would become permanently bonded to the coil, and the tackyness was enough to get the job done.
Because I didn’t wait for the glue to dry, it was easy to rub the outside layer off in to little balls and peal them off. I then applied the super-glue outside shell for real structure. I tried to tack the coil together as best as I could before removing the second side of the form, being very careful to get no glue on the form, as I’m pretty sure CA melts Acrylic. With that, I present 4 completed coils, ready for install, on a slab of granite.
Now I just need an aluminum frame to install them in…
P.S. I’ve noticed people are visiting my site after searching for Laser Galvos– I invite you to please leave a comment or ask a question; I’d love to hear what you are doing in this field and what you think of my project.
