Books are great but they don't make really basic things clear

I made a hard stop for each of my lathes with a dial indicator included. I have it set so that the needle starts turning at the 1/2" point before the hard stop. I can disengage the clutch at about the 0.005" point and finish by hand.
 
Yes books are great and I enjoy the ones I have but I am not sure the operators manuals discuss the basic controls thoroughly, sorta like learning to drive different automobiles.
Are you using a small radius on the tip of your cutting tool? I have fond this helps even when hand feeding. Try as we might it is difficult to move the carriage small distances uniformly per revolution of the spindle when hand feeding but the lead screw will do that extremely well.
A lot has been said in the pre-cedng posts about fixed carriage stops, believe every word about potential damage. IMHO metal working machines are like an automobile, they won't drive themselves!
Have a good day
Ray
 
I don't know a lot about SB 9's, but doesn't it have a star-wheel just below and to the right of the carriage hand feed wheel?

Like this:
1540522313710.png
If so, that star-wheel engages the feed clutch, which is used for turning. The half-nuts are only used for threading. The feed clutch is a little more forgiving, it will slip if you crash up against something hard.

Of course, I could be completely wrong. Your 9 may not have a clutch.
 
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Not sure if I understand your question so must ask if you are looking for a good book on lathe operation?
Using the power feed and lead screw are well described in some books.
I suggest that you set up some practice runs for both operations so that you can build your confidence in using the half nuts and feed clutch/engagement on your lathe. You do not even have to make chips, just run the lathe within safe limits.
To me it was about breaking the ice on both operations as opposed to breaking the lathe. You are wise to want to understand the pitfalls and avoid crashes but this should not prevent you from getting the full use from your machine.
 
One key to a good finish (even when advancing the carriage by hand) is to have the radius of the tool larger than the distance it is advanced with each turn of the spindle. Secondly match the spindle speed (surface speed per Minute) with the material being turned. Also keep in mind one cutting profile does not work for all materials. The profile for copper and aluminum will be different than one used for stainless or cast iron.

Here's a quick tutorial on the different tool profiles used on different materials:
http://www.steves-workshop.co.uk/tips/toolgrinding/toolgrinding.htm

Here's a link to a quick tutorial on speed and feed rates for different materials:
http://www.engineeringenotes.com/in...turning-problems-industrial-engineering/27210
 
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