The turning can all be done in the lathe assuming you can swing that dia. Your drawing does not show if you intend to have spokes or a solid disc, the spokes particularly if tapered are easier done with a rotary table but could just as well be done with some carefully positioned holes, some sawing and then careful filing.

One word of caution with ali flywheels is they don't have much mass so if you are copying a design that calls for brass, bronze or iron you will need to add a lot more bulk to the flywheel or up the dia.

 J

Edit just enlarged it and you are having spokes so yest it can be done without a RT but would be easier with one.

Edited By JasonB on 03/04/2012 16:11:11

Hi Bob,

As Jason says you need to re design the flywheel so the it will have the same moment of inertia as one made from diecast metal. The density of aluminium is about 2.7 gm/cu cm Diecast metal has a density of about 6.8 gm/cu cm (about 2.5 times the density of aluminium.) I think I have seen a reference to someone making a flywheel of of aluminum then drilling holes all round the outer edge of the flywheel then filling them with lead. This seems a lot of trouble to go to. Have you considered collecting diecast metal and melting it down to cast into a disk in a suitable tin can.

Les.

Thats an awful lot of filing, can't you make a composite item in steel? would have more mass too.

Bob, I'd tend to make the rim at least twice as thick as the drawing shows if possible, another way of adding weight would be a steel (or other heavyer metal) tire on the outside of the rim. I made a flywdeel that way (its on one of the motors in my album) the cast iron rim is pressed in to the part with the spokes made of 1/4" steel plate, with the hub brazed in. The rim is attached with 6 3/16" countersunk screws. The complete wheel is 6" dia X 1" across the face of the wheel. This type of construction would suit aluminium spokes, the screws could go straight into the end of the spokes. On a little oscillator I built at a schoolnight class the only metal available for the flywheel was 40 mm dia aluminium, the engine would only run at high speed, I took along a bit of brass, an made another flywheel, the engine would then run at just a gentle tick over, don't know who designed it, but I redid the drawing for it, improving the performance and looks of the engine, and saved about 25% in matials, enough to make it about the same cost with a brass flywheel. Ian S C

Thanks for the vidio Terry, worth the look, only took 1hr 20min to get to about 15 sec before the end, then it dropped out, thats dial up, never mind saw enough to see a worthwhile bit of work. Ian S C

Yes you can either use a boring bar to do the outer face of the web & inside of the rim then change to a facing tool to complete the face of the web and hub. Or if you don't have a screw on chuck leave the boring bar in place and work from the back with the lathe in reverse.

The other way is to use something like a rounded parting tool held parallel to the lateh axis and work across the web face with this. A tool like this is better when ther diameters are smaller or distance between faces less, used it on these.

Aluminium has a low density compared to other metals – typically a more dense metal would be used for flywheels.