How to advance a spin index the number of degrees desired while milling round stock. The spin index is an inexpensive tool for incrementing full degrees that will evenly divide into 360 degrees. For example one can increment 15 degrees because 15 will divide evenly into 360. If you want a machine that can increment. lets say 15.73 degrees then you would need a more expensive tool called a dividing head. Note that I made a mistake on one of the teeth while making the video. It was the result of not having full focus on what I was doing because of making the video. You should only do this type of work when you know you won’t be distracted. It is very frustrating when you screw up a gear and have to start all over again. The video where I made the mistake is titled ‘Cutting a gear tooth using a spin index’
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