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Continued:
I flattened out the defective coil to roughly determine the inside and outside perimeter dimensions. The approximate thickness of the thickness was a 1/4 inch. I cut a 2.125 x 2.375 x .25 plastic form for a bobbin center. Cut some acrylic squares for bobbin ends and screwed it altogether.
I wound a practice coil first with 38 gauge wire. I used enamel wire gauge resistance charts to calculate the amount wire to use for the winding. I based the coil size on the rough flattened old coils' dimensions. After I finished winding the coil, I checked its' resistance and inductance; 345 mh and 725 ohms. This first coil wouldn't work I realized. The inductance and resistance were too great. I was worried about the maximum current the coil could handle also.
I had to order a pound of 36 gauge wire to wind the coil with since it could safely handle 70 ma. I over wound the second coil by 125 percent. Ended up using the extra wire to wind a duplicate vertical coil.
The motor I use for winding runs at 72 rpm. I calculated the average length per turn of the coil to be 10 inches. This gives 720 inches or about 60 feet per minute. The resistance per foot of 36 gauge magnet wire is about 0.413 ohms per foot. With a needed resistance of about 463 ohms divided by 0.413 ohms/ft , I came up with at least 1122 feet of 36 gauge wire. Took the 1122 feet of wire divided it by 60ft/min , comes to about 18-19 minutes of winding at 72 rpm.
In the end I ended up with two coils measuring about 265 mh with a resistance of 470 ohms each.
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