Welcome to the Forum! I have never heard of replacing the shaft! I agree that for Your purposes, go with a extension. 1/4 to 1/4, or 1/2 to 1/2! There isn't anything made to increase shaft size! It any one tries, they would be putting themselves in very serious danger! Thanks for joining. You will find a great deal of information, and very good people to help You along, if You would ask! That's what We like to do, is help others get as much knowledge, and satisfaction as possible!
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