I have done several using 3-jaw and 4-jaw chucks as well as faceplate. Of the three the 3-jaw would be the least suitable as you can't easily adjust the rim true

A lot depends on the size of the flywheel in relation to the chucks/faceplates/lathe available, number of spokes and how true the inner edge of the rim is to start with. Do you have a particular flywheel in mind and can you remind us of the size of your equipment.

J

Have you seen this video from Tubalcain2 (MrPete222)?

**LINK**

Jon

Here are a few pictures of machining the flywheel for my 6" Burrell, the flywheel is 25 1/2" diameter on a 27" faceplate, the keyway was cut on an 8" slotter.

Richard.

This was how I did my Wyvern flywheels:

File off all the flash and and any lumps on the faces of the rim.

Most flywheels are cast with a split pattern so registration between the 2 halves may not be perfect. Choose a side to be the "outside" i.e. the side that the engine will be mostly viewed from. Mount this side out on the faceplate with 3 sacrificial pads (ally in this case). Try to get the inside of the rim running as true as possible. Take a cut across the face of the rim and the circumference.

Now reverse the flywheel and centre on the faceplate using a DTI on the rim circumference

The sacrificial pads allow you to take a cut across the whole of the rim circumference

The video shows a mis-registration problem. The "good" side of the rim was fine but you can see the eccentricity on the reverse side. Not too bad for the Wyvern since this has twin flywheels so both of them can be mounted with the good side on the outside – less easy to hide on a single flywheel steam engine.

Hope this helps,

Rod

Edited By Roderick Jenkins on 19/05/2014 19:42:15

Me!

Works fine for small flywheels, up to about 3 1/2", also a way of helping ensure the outer diameter is wobble-free. Not sure it's the best way for the heavy mob. About the ONLY way to finish pulleys of 1 1/2" or less in diameter.

Has the advantage you can machine all three 'sides' of the rim at one setting (unless it's recessed).

Neil

Should clarify, I use a 4-jaw to turn and ream/bore the boss, then mount on a mandrel to finish the rim.

Neil

By Ek lads your getting competitive with this one.

Boiler

I would say your eye should be better than a DTI in this case. Running the DTI on a cast surface you will never get it to Zero. Its usually easier to have a lathe tool or bit of bar in the toolpost that just clears the inner face so as you turn the part round by hand you can see where the flywheel is moving, aim to get as small a change in the gap as possible. DTI is best when you reverse the flywheel to do the other side

Does depend a bit on the design of the flywheel, some you can just machine the outer face and two edges others need a bit of a cleanup behind the rim and to the sides of the outer web.

J

ARC do them but its an ideal little job making your own that will get you used to using the lathe and far cheaper too.

J