Having got most of the flywheel tidied up, just requiring a few more hours to finish it off, I decided I need to make the combined power takeoff pulley and flywheel/crankshaft clamp. For models such as this, which don't have too much power, I prefer not to drill or make special fittings for the flywheel, that way, they always run nice and true. The crankdisk is first locked on, then using spacers and other components right the way along to the other end of the crankshaft, the whole lot can be tightened up together, as long as the flywheel turns in the correct direction for tightening up the screw/nut.
For many years now, I have been picking up very old sash weights from the scrap yard for pennies each (on average 30 pence, about 50 cents US). These give me a great source of very fine grained cast iron up to 1 3/8" diameter.
I stuck the weight onto my power hacksaw and soon had a 2" long lump for my use.
Unfortunately, with these cheap materials, you have to put a bit of work into it to get the good stuff out. In this case, the hard casting skin, which if attacked with a normal pointed carbide tip or HSS they would be flattened or broken in seconds.
I use the wide angle part of the tips in a special facing roughing tool holder.
The same goes for the main outer skin, another type of roughing cutter removes it very easily.
Very quickly, I was the proud owner of a piece of over 100 year old, super fine grained cast iron bar.
So a C-o-C was drawn up to give me a working drawing of what I wanted.
You may have noticed that I am working with my lathe in 'Myford' mode, I will be swapping this chuck over onto the mill RT once the pulley has been roughed out.
The outer face was relieved a little for when I get it onto the mill in the final stages for cutting the half round drive belt slot.
Both sides now needed a 7mm deep recess cutting into them. So a quickie grind up on the offhand had a rough trepanning tool that will do the job. It left a few chatter marks on the bottom face, but I was not worried about those, they can easily be cleaned up later.
This is where it will be mounted when finished, compressing everything up nice and tight into one long unit.
Notice how nice the finish comes out on this material, no polishing was done at all, just basic deburring.
Basic lathework done, time to get onto the RT to have a bit more machined off it.
After some very rough calculations, and by use of the Divisionmaster, I had all the holes in the right places.
Then it was just a matter of joining up the holes using the X & Y axis of the mill and the RT in manual mode.
I also put a few more slots in as well, as shown on the next pic.
This is an awful pic, it looks like the spokes are all twisted and the wrong shape, but in fact, I hadn't deburred it before taking the shot, and what you are seeing are mainly shadows from the heavy burrs being thrown up by the flash on the camera.
Once deburred and cleaned up with a bit of filework, it will look spot on.
This will now be put to one side, until the flywheel has been finished off, and when I have the RT set up to vertical for another job I am doing, then the half round slot can be finished off.
Bogs
