New guy asks what good is a reverse motor switch

[twooldvolvos]

I'm brand new to using my South Bend 10k lathe. In fact I haven't made any chips yet. But I have done a lot of hand turning the chuck. One thing that has me confused is it looks like my motor switch has a reverse position. Why would I want to reverse my motor? For one thing, I understand it could spin my chuck off. Also, I believe I can reverse the apron with the motor in forward. Can someone explain what operations the reverse direction of the motor will be helpful with? Thanks.

 

[BGHansen]

Nice to have if you power or even hand tap. Pop in reverse to back out the tool.

Also nice if you cut a metric thread or one where you can't use the thread indicator and have to leave the half nuts engaged. Make a pass, stop the lathe. Back out the cross feed, and reverse back to the starting position for the next pass.

Not too much of a worry when using the back gear. Not as much inertia as with open spindle.

Bruce

 

[mattthemuppet2]

cutting internal (female) right hand threads away from the chuck is another use too.

 

[Jim F]

Reverse threading when using collets......

 

[Jim F]

cutting internal (female) right hand threads away from the chuck is another use too.

Real light cuts.

 

[Ulma Doctor]

Cutting left hand threads

 

[Jim F]

Cutting left hand threads

That can be done without reversing the motor.
Now, reversing the motor and engaging the reverse lever, that is a one of a kind thread !!!!!!!!

 

[Jimsehr]

I used to run a couple thousand shafts a month. They were 1/2 dia and 12 inch long. And after cut off they had to be faced to length and chamfered. So for production runs where I didn’t stop the spindle I would use a 5c collet with a stop about 1/2 deep Into collet. Then also used a steady rest with rollers set up about 10 inches out from collet. Then with machine running in reverse and using a lever collet closer and one tool Ground to face and chamfer all in one and tool set upside down on front side of lathe cut parts to length. Because the cut forced the part down into the 2 rollers I didn’t have to use the top roller of the steady rest. This way parts could be loaded and unloaded in seconds. Way faster then loading into collets.
Jim Sehr

 

[twooldvolvos]

I used to run a couple thousand shafts a month. They were 1/2 dia and 12 inch long. And after cut off they had to be faced to length and chamfered. So for production runs where I didn’t stop the spindle I would use a 5c collet with a stop about 1/2 deep Into collet. Then also used a steady rest with rollers set up about 10 inches out from collet. Then with machine running in reverse and using a lever collet closer and one tool Ground to face and chamfer all in one and tool set upside down on front side of lathe cut parts to length. Because the cut forced the part down into the 2 rollers I didn’t have to use the top roller of the steady rest. This way parts could be loaded and unloaded in seconds. Way faster then loading into collets.
Jim Sehr

Thanks for your reply, Jim. I can see that production work is on a whole other level.

 

[Tozguy]

Reverse is a necessity on my hobby lathe for cutting metric threads. As Bruce mentioned, the half nuts stay closed so the only way to get the carriage back to the start point is using reverse. This does not put any torque on the chuck wanting to unscrew it.