Written by Marvin Guthrie
Published by David J. Gingery Publishing, LLC
5-1/2 x 8-1/2 Paper Back. Perfect Bound. 55 Pages.
"Back gears" are just what their name implies. A set of gears mounted at the back of the headstock on a lathe. Their purpose is to allow the lathe spindle to rotate at slower speeds while at the same time delivering greatly-increased torque.
For example, prior to adding back gears to the Gingery lathe, the lowest spindle speed that could be achieved with the suggested pulley arrangement was 172 rpm. Adding back gears, gained a range of high torque speeds from 43 rpm to 268 rpm.
One operation that really benefits from those slower speeds is thread cutting, especially if you are a beginner. With back gears, your lathe not only becomes capable of doing a better job of cutting threads, it also allows for increased drilling capacity, larger hole boring and larger diameter facing. Simply put, back gears will enable your lathe to be used at its maximum strength and capacity.
If you have built the other Gingery projects in the "Metal Working Shop from Scrap" series, you have all the necessary tooling for the job. And here in this booklet, Marvin provides you with the step by step instruction beginning with the patterns, molding procedure, machining the castings and finally fitting the individual parts on the lathe. Included are many detailed drawings and photos that help make the project easy to understand.
And for a final touch of class, Marvin shows you how to add a change gear cover, back gear cover and front cover to your Gingery lathe.
This is a truly delightful project. If you have built or are planning to build the Gingery lathe, consider adding back gears. You will be glad you did!