Too simple ?

Attached photo shows a gear wheel together with its unfinished copy.

My question is how do I cut the two lugs/dogs accurately, should I bore the centre hole to size first ?

Photo added by JasonB

Edited By JasonB on 05/04/2016 13:26:37

No photo. Did you make an album on the site first?

I'd bore the hole, then holding the gear down to the mill table indicate the centre of the hole or boss. Then mill equal amounts off each side until you get to the required width of the dog teeth

Agree with Jason. I'd bore the hole and turn down the boss if it's not yet to size then clamp it down on the mill to cut the dogs.

Please let us know how you get on and don't forget; it's not simple until you know how to do it.

Edited By Brian Hutchings on 05/04/2016 15:10:31

Yes, bore the hole first. A couple other options for holding the gear on the rotary: in a 4 jaw chuck using soft metal pads on the jaws, or make an expanding mandrel and hold that in a chuck, either clamped to the mill table or on the rotary.

So what is it for? I take it the lugs are used as part of a "spline drive" motion or spur?

Roger,
Does your accuracy requirement include angular alignment of the dogs to the position of the gear teeth?

Bob D

The lugs connect to a cush hub in a flywheel,so the alignment of the dogs to the gear teeth is irrelevant.

JasonB.....I have a small horizontal mill....what recommendations would you make for that?

Thanks for all the comments.

How about this as a method?

As already said, Bore the hole first, then mount on an arbor, mounted vertically, in a vice, on the mill. Use a Side/Face cutter to remove metal, gradually, from one side, and when one side of dog is to size, (Radius plus half dog width), repeat on the other side.

Howard

Buy a vertical mill

As well as the overarm method mentioned above by howard you could just put a milling cutter in spindle socket, mount gear on a horizontal arbor facing the spindle or clamp to an angle plate then mill in the same way I originally suggested