How to convert a Harbor Freight 1x30 belt grinder to DC variable speed reversible for sharpening

Converting a Harbor Freight 1x30 belt grinder to DC variable speed reversible. This makes it easier to sharpen tools without overheating them or removing too much metal. The video has slides and audio that explain the details of the entire process of conversion and then videos showing it in use. A belt grinder is one of the simplest and easiest motorized ways to sharpen! I use it to sharpen all my wood lathe tools but also my chef's knives, scissors, and even my pruning shears. There are many tutorials specifically about sharpening - this one is about how I modified the AC grinder to make it much more versatile along with an easy way to reproducibly set the angles. Sharpening lathe tools does not need to be expensive. I spent about $150 USD including the original tool. The fixed angle jigs I show cost nearly nothing and the bowl gouge jig is made from a pegboard hanger, a piece of PVC pipe, and a bolt. Be sure to read, understand, and follow all of the instructions that come with your tools. I am not responsible for, well, anything you do with them! This shows how I did it and you are most definitely on your own.