Burrell Traction Engine

(How to Machine Internal Keyways on the Lathe)

 

It has been necessary to machine keyways in the bores of several turned parts for this project. I thought that it would be helpful to show a few pictures illustrating the method used by me to ensure that the keyways are accurately positioned. The tool is set up square and on centre and then is wound back and forth to shape the keyway using the saddle handle of the lathe. The depth of cut is applied using the cross-slide handle.

The driving boss has been used as an example of the keyway method as it is appropriate to the hornplate arrangement.

The left hand image shows the Driving Hub casting prior to machining.

The right hand image shows the finish machined article (including four drive pin holes).

The left hand image shows the method used to lock the spindle for keyway cutting.

The right hand image shows the dummy centre used to assist scribing a centreline.

The left hand image shows the set-up for a bar to scribe along.

The right hand image shows the bar offered up to the job ready for scribing.

The left hand image shows the keyway cutting tool held in the toolpost.

The right hand image shows the finished keyway.