I have a Craftsman 6" metal lathe that my dad purchased new in the early 1960's and a few years ago the set screw hole that secures the pulley to the key on the motor pulley stripped out. As a temporary fix I drilled and tapped a new set screw hole but it does not secure the shaft key properly. The pulley (as well as the original gears) is made out of a product called Zamak and while it was a great metal to introduce a low cost lathe to a growing hobby the material is not user friendly as far as welding it. The way the pulley was produced was what I would call economical without any excess material and as a result there is not much of a way to sleeve the pulley and attach it to a new hub. Due to the age of the pulley it is also becoming worn in the smaller v groove since this is where the belt runs a lot of the time.
I have decided to try and make a new pulley out of steel which will make it a little heavier but also much more durable. Thought I would do a post on it as others may encounter a damaged, worn or missing stepped pulley in other applications and think that creating a new one may be virtually impossible. Normally I would check at the local hardware store and see if they had any ready made pulleys in stock which I did but did not find any that could be easily adapted since most V belt pulleys are made for 1/2" wide belts and the lathe uses 3/8" wide belts. While owning or having access to a metal lathe is a definite necessity to making a new pulley on initial inspection of the original pulley one might think that it would be necessary to have a chunk of round stock approximately 3.25" OD by 1-1/2" wide and while that would work I am going to form the pulley out of 2 pieces of steel I had laying around left over from other projects. The other benefit of making the pulley in piecemeal form will be to cut down on the time to machine the smaller diameter of the pulley step. Got the two pulley diameters cut out of a piece of 1/2" x 6" flat steel approximately 3-1/2" wide and a short piece of 1" round stock will be used to create a hub to mount the flat steel pieces to. Used the chop saw to cut the piece of 1/2" flat steel into the three smaller chunks. The circle diameters were marked out on the two pieces of 1/2" flat steel and the centre marked with a centre punched. Once the O.D. of the circle was marked I used a hack saw to cut the four corners off and then used the sander with a flap wheel to round the outer edges to change the shape from rectangular to reasonably round. This will save time when the two pieces are mounted to the centre hub and trued up before they are turned to the correct size and width. Used the drill press and drilled a 3/4" hole in the two flat pieces of steel.
Edited by 29 Chev, June 10, 2020 - 12:40 PM.