Making Pulleys

Our great friend Lionel Oliver has a booklet on pulleys, but I'm too lazy to buy it, so here's what I've thought up.

Pulley Pattern

This is my first pulley pattern. I started with a pine 1x4 blank, cut out a circle with the jigsaw, and drilled and yes, tapped a 1/2-20 hole in the center. This allowed me to thread it up on the tailstock ram (just a threaded cylinder.. see wood lathe), which I chucked in the drill press. Then I got out a small chisel and yep, I turned the groove in it! It took forever and stalled often, so if I'm going to do this again I think I'll take some pink foam and do it lost-foam style or something, like Frank does everything.

After turning it to shape, I glued the hub on, then took it back over to the jigsaw and cut it square in half. I then drilled the holes for the alignment peg, which ensures that the two halves are aligned as the sand is rammed in around. (But it doesn't help when the sand doesn't stay aligned. See below. ;)

It took me three tries at molding this POC before breaking down and dipping it in wax as shown (I'm way too impatient to wait for varnish to dry!). The problem was the piece with the peg, the cope half, well no matter what I did, a piece of sand would always stick in the same place in the V-groove. (This coincided with where, when turning it, the wood was being cut sharply against the grain. I don't blame it for being rough!)

Cast pulley side

After waxing it and filing the remaining rough spots I molded it, and it worked finally!! Just look at that finish...

Ok so it isn't perfect...

Yeah, ok, so I really fooked on the molding. 8-( Guess I should put alignment pins on the 6x6 flasks some day...

Part 2

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