Micro Coil Winder

This was the first, fairly complex piece after a month or so of getting to know my Little Mini! I call it my "Steam Punk Micro Winder". I thought about mounting it on my hat or coat, but mainly wanted it to build 6 baby coils for a little 3 phase micro axial generator for a larger project in the works. The reason they are so small is that the 6 coils needed to fit on a 3" disc and had to have certain number of turns to achieve my goal. It turned out pretty well and you can see the first coil I wound on it. My winding skills got better as I went along. 8-)

At the bottom of the page you will find my drawing for these parts in detail. I ended up changing the Hub design a bit on the fly, primarily because the .032 carbide circuit board drills kept breaking off. The thickness of the flanges were just too much for them to handle and quickly ran through the three I had. If you look at the picture above you'll see I notched the outer edge holes instead and it worked fine for ending the coil wind.

The hub pieces were pretty easy to make on the Mini. I started with a piece of 3/4" stock and turned it to .625 and enough to make both pieces. Next was to bore the .195 hole, deep enough to get both parts. Then turned down the center spool to ø .250 and back about .295 giving me enough room to face the end a bit and achieve the .2663 inner width of the spool. Then I parted off that piece leaving a skosh to clean up if parting went haywire. I marked it at .412 and the parting worked pretty good, so later I chucked it up backward and faced it off to the .407...which actually isn't a critical dimension...it's the inner dimension that was critical.

Then I faced off the piece still in the chuck and set up a .25 end mill in the tail stock with the Dial Indicator mod. It came in right on the money at .016 deep. Parted off that side of the spool and proceeded to all the tertiary Operations...drilling the blinki'n tiny holes and the 4-40 blind hole tap for the handle...I guess I like a challenge. @¿@

When I first joined the two parts to check the coil space dimension it was almost perfect so I just touched up the center of the spool on the granite with some 400 W/D until I got to .2663! I also parted off the brass tubing sleeve for the crank handle in the mini.

In the last picture above you'll see some black washers; they are #10 shoulder washers for rack panel screws. They created a nice bearing surface on the brass plate so it didn't wobble while cranking and winding. I actually turned one of them down for use on the right side of the crank by chucking up several of them on a 10-32 screw. This was necessary because it had to clear the head of the little 4-40 socket head that locked the crank to the spool and support the head of the axle screw. Also, if you can see them there are some Baby, Baby plastic washers on both ends of the brass sleeve for the crank handle. They out of a VCR I salvaged...and they worked perfectly with the 4-40 handle screw.

Overall it was great fun and actually worked to specs. There were some frustrating moments at times with the drills and notching but everything I did on the Mini worked terrific!