The lead screw if long should be supported, to prevent its sagging of its own weight.
Unfortunately, the gearing which once existed to connect the headstock spindle with the lead screw has long been lost.
An apron on the front end of this slide carries the lead screw nut h.
The screw-cutting lathe, which is provided with a lead screw, by means of which other screws may be cut.
Means are also provided to reverse the direction of lead screw or feed screw revolution.
The lead screw of a lathe is a screw for operating the lathe carriage when it is desired to cut threads upon the work.
It is obviously preferable, then, to place the lead screw at the back, where the carriage and shears wear the least.
To prevent end motion of a lead screw it should have collars on both sides of one bearing, and not one at each bearing.
It has also a feed rod for the ordinary tool feeding and a lead screw for screw-cutting purposes.
Find the pitch of the lead screw, and at the head of that column is the number of teeth for the lathe stud or mandril.