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Why 'Reverse' on a lathe ?

ChipBed

Aluminum
Joined
Jan 7, 2005
Location
Rochester, NY
One of the other posts got me to thinking, but why would you ever need 'Reverse' on a lathe? My 13" has a 'Forward' & 'Reverse' drum switch, but I've never found a use for the reverse direction and, in fact, I mechanically locked it out, so I wouldn't accidentally start it up in reverse. Is there a time you'd run it backwards (maybe to put stock on? :D ) ?
 
the most common reason to reverse a lathe is when cutting metric threads. you can't disendauge the halfnut with an english leadscrew and thread dial. Another good reason is when turning or boring bronze, cast iron, micarta you can flip your tool upside-down and control chip ejection, although i dont think i would try it on a screw on chuck.
 
You can reverse the lathe when threading without a thread dial. You just leave the half nuts engaged and reverse the lathe to move the carraige back to the other end to start the next cut
There's one I hadn't considered!
Thanks,
-Bob
 
Reverse is used when you power tape. Threading away from an internal shoulder, cutting internal groves so you can see the tool. Cutting angles with the compound--easer in some cases. A lathe with out reverse is crippled.
 
I often do internal operations, such as boring, threading and cutting grooves for O-rings or snap rings on small pieces running the lathes in reverse. I grind the tool bits from HHS blanks for reverse operation, (mirror image). Doing it this way, you have a clearer view of the bore and the cross slide and compound are going in the “right” direction.

ExpTec
DBA Experimental Technique
 
All of the above mentioned uses plus youi can do a quick chamfer on the OD of a part by just angeling the tool bit and running it on the outside of the back side of the part while running in reverse.
Can also use a standard boring bar to do this using the compound in the normal direction. This is somtimes helpful if you are using a steady and you need a tool with a long reach to get in to the work area..boring bars on the back of the stock with the spindle in reverse. (need good cross travel for this one.)
Cheers Ross
 
ChipBed don't feel bad, there is probably over a hundred years experience that just posted to you. Just a guess I have over 40 my-self. That is what this web is for
 
Another one: to turn matching ID and OD tapers. Bore the ID taper in forward and the OD in reverse from the back. This way you can match the tapers exactly without resetting the compound angle.
Question: Has anyone out there come up with a good way of locking the chuck to a threaded spindle?
congrats everyone--this is a great thread
 
For ID threads - make a "wrong handed" threading type boring bar and you can cut right hand threads by backing the carriage out away from an internal sholder. Feels much less iffy. Start thread in relief groove of course, and swivel compound "the other way".

John
 
Chipbed, I'm glad you asked that question! My next lathe project is a hub for a mini-bike which needs snap-ring grooves for the wheel bearings. It never occurred to me to cut in reverse so I'd actually be able to see what I'm doing. I love this site, I get answers to questions I didn't know I had!
 
When drilling soft metals like brass, and the bit grabs pulling it out of the tail stock taper. My motor is instant reverse. I can throw it in reverse to instantly unbind the bit.
 
I do a lot of my O.D. right hand threading in reverse. I turn the tool upside down, start the thread at the shoulder, and then feed down the part to the tailstock end of the bed. That way I can start the thread right next to a shoulder without worrying about running into it.
 
I'd like to revive this old topic, as I ran into a situation while cutting a snap-ring groove with the lathe in reverse so I could see what I was doing. My 10L has a threaded spindle, as I guess all SBL do. This made the cutting tool a power chuck remover! With very light cuts it didn't come loose after screwing the check on more tightly than usual, but what a mess! my beutifully finished bearing seat has a great big gouge in it, and it could have been dangerous. Luckily the lathe was running at fairly slow speed, and I was being very tentative with the feed, as this was my first experiment with such an operation. How to guard against this?
 








 
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