Some one convinced me to modify an Atlas TH54 lathe into a pool cue taper lathe.
Modify lathe to turn thin wood pool cue shafts with long taper
CNC would not be used
Modify lathe so compound will follow taper templates
Select easily between several taper profiles
Continuously variable spindle speeds
Continuously variable lead screw speeds
Limit switch at end of lead screw travel to shut off lead screw and spindle
Large metal backdrop and structure and dust shield
Modify an Atlas lathe so that the compound and cutting tool position would be controlled by a taper template. The compound slide was disconnected from its lead screw. A bearing was attached to the compound slide that would bear against the taper template. Springs were used to insure that the bearing stayed in contact with the profile. Multiple cue shaft template profiles were to be used. Both lathe spindle and lead screw were to be independently powered and speed controlled allowing for feed and speed tweaking. A limit switch was installed at the limit of travel to turn off the lead screw and spindle after a taper pass was finished.
First step was concept and fab of how to switch easily between taper templates. Design was to mount multiple templates on a square tube and rotate tube to change tapers.
Cue shaft taper measurement. existing cue shafts were used to generate the taper for a given template. This was accomplished by measuring the diameter of the shaft every 1/2 inch along the length.
Cue taper measurements were performed on 3 shafts of 2 different designs. The graphs show the diameter of the pool cue shaft along it length. Theygo from about .5 inch diameter to .85 inch diameter.
A single template dxf was drawn up from the shaft measurements for the two profiles we were interested in. In addition a two level constant diameter template was drawn to assist in cutting dowels of a specific diameter.
Template tube mounted on back plate. You can see the all thread bolts used to maintain the distance between the vertical plate and the lathe. You can also see the cross slide extension with bearing that rides against the template taper. Not yet mounted are the springs that will force the cross slide to maintain contact with the taper template.
Template tube mounting detail. The steel plates in the interior are nutplates for the taper template that are about 6 inches long. That was done so that the nuts could be aligned from the end of the tube.
Next task was mounting the router.
Limit Switch mounting. Again the CNC knees mill made simple work of the slots. The switch wheel contacts the underside of the apron when the cross slide is close to the headstock of the lathe. The lathe spindle and the lead screw motor are turned off with this limit switch.
The Lathe schematic is basic. A VFD controls spindle speed. A DC motor controls lead screw speed. A contactor is used as a high current relay. Both VFD and DC control are hooked into the limit switch.
You Tube of lathe cutting some dowels