Spindle Design and Machining

Section view of the spindle with bearing placement shown

Milling flats for releasing the chuck

All the pieces ready for final assembly

Completed spindle shaft

Bottom mounting dovetail on housing

Setup for making precision nuts

2.5" 4130 ready for roughing

Re-indication for finishing

Spindle shaft with step pulley mounted

Clever technique for ensuring concentricity between spindle nose and bearing journals

Fixture for dust cover

Assembled Spindle

Turning a bowl on the lathe

Learning

Deep dive into spindle design and bearing selection
Lots of intricate manual machining to tight tolerances
Tribology and its relation to ball bearing design and construction
Working on a team on a more complicated mechanical assembly

Description

For the final project of my Mechanical Design course, my team and I designed and built a small wood lathe. I ended up working primarily on the headstock and spindle design and manufacturing. From creating a list of design criteria, to bearing selection, to the actual machining this project presented substantial technical challenges, but was very rewarding to see the final result and have it function as designed. I don't know if I'll ever make a more complicated manually machined part than the spindle shaft, but I am glad to have had the time to spend on the very nice engine lathes in the Olin Shop. The requirements I set and the machining process is more thoroughly documented on the project website.