Rocker or crank shaft

[Johan Theo Maritz]

Hi i would like to pick the brains from the experienced. How would you machine this part. I have done a few and must admit it is a pain. You will see from my sketch how i do it from a disc of material twice the size of the actual part, it works, but it is a terrible waste of material. Any clever ideas as how to approach this. I assume you can build it op from two parts as well, but is becomes difficult when it is so small. Any smart youtube links maybe of a clever method. These parts are used all the time in all kinds of engines, surely there must be a better, easier way to machine it?

 

[Jasonb]

Make it from rectangular section material, either off the shelf bar or machined down from something larger.

Do the holes first while it is easy to hold. Then mill the tapered sides.

Make a simple mandrel and either turn the boss in the lathe or do it in the rotary table which will also allow you to round the larger end radius.
File the small radius with the aid of filing Buttons

 

[Johan Theo Maritz]

I immediately caught the idea, excellent, that will work. Why did i not ask earlier. Thanks the pictures explain it all, so simple, yet it evaded me.