Sherline Rotary Broach

Description

This adjustable rotary broach comes centered and ready to use, as long as the punches used with it are 30mm in length 8mm in diameter.
All the components of it are made in the USA, except for the bearings, which are imported from Asia.
Punches not included, Tormach does have them on their web site and they are 8mm in diameter and also of the correct length.
The shank has a #0 Morse taper it fits the Sherline lathe tailstock.
Should you need to adjust this rotary broach to use a custom punch or a punch of a different length than 30 mm all you have to do is loosen the four set screws on the outside of the body, loosen the 5 mm socket head screws on the back to the point where they are just snug. Place the broach on the lathe's tailstock, get the punch close to a cone held within the lathe's spindle and collimate the hole of the punch with the point of the cone held in the lathe's spindle. Once they make contact by adjusting the four set screws, tighten the 5 mm socket head screws.
Here's how to use it:
Pre drill a hole into the work that is 3% larger than the distance between the flat to flat (opposing surfaces) of the punch, the hole should be 1.5 times the flat to flat dimension of the punch.
Chamfer to lead the punch into the hole, chamfer should be .005" per side larger than the distance between the opposing sharp corners of the punch used.
Feed at 400 rpm using cutting oil.
At the end of the broaching operation you may have to clean up the bottom of the hole using a drill bit, as the swarf will accumulate and get pushed to the bottom.
Here a link to my video on how to center it:   https://www.youtube.com/watch?v=GpyKSNkJJ2w