When having to drill repetitive holes in parts as second operations on an engine lathe, having a means to automate the tailstock could prove valuable.
Not all lathes come with the option of a hydraulic tailstock and some only have limited action.
The following are two basic ideas that can be implemented on virtually any lathe and very quickly as well!
Attach a suitable pneumatic cylinder to the bed using a similar clamping method as used on the tailstock itself. Have it push the lightly clamped (but free sliding) tailstock. A restrictor to control the feed-rate is mandatory. This method requires no modification to the lathe, if you need it to also retract through pneumatic action you can use a bracket or clamp on the tailstock. Otherwise you can push it back by hand as usual. Using a second restrictor on the return valve could help lengthen the life of the cylinder, so you don’t constantly ram it to fully closed all the time.
With a long arm and bracket mounted on the toolpost, one can have the tailstock move, when the auto-feed is engaged on the carriage. This method has several limitations but it only requires light fabrication on mild-steel or aluminum for the “pushing arm”. While you can adjust the feed, it won’t be as flexible as the pneumatic cylinder, and you’ll have travel limitations in some cases.
Of course, the obvious alternative is to have the tailstock mounted in front of the carriage, and have the carriage push the lightly clamped (but still free sliding) tailstock.
Whichever method you choose, be careful and keep in mind possible crashes or tool ruptures. These are NON-CNC methods, for any type of electrical control you could, in theory, easily mount a stepper motor to the quill feed on the tailstock, but that itself is a modification of the lathe and beyond the scope of these two simple methods.
As for peck-drilling, the second method won’t allow it, this is why I’m starting to work on a clamp system for a pneumatic cylinder, peck-drilling with a pneumatic setup is relatively easy (although it may be expensive for some). The whole idea however is not to modify the tailstock in any way at all.