New Lathe: Feed direction?

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Philipintexas

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I love my new lathe, however the feed directions are totally screwed-up, at least to me. If I do a turning cut toward the headstock and then a facing cut out away from the lathe axis, I have to change the feed at the apron to engage the cross-slide, stop the machine and reverse the lead screw direction. Every lathe I've seen only required a change of feed direction at the apron. Have I led a sheltered life or is this just a bad design?
Turning toward the headstock and changing the apron control alone results in the cross-slide feeding IN toward the axis of the lathe? I cannot imagine this being normal ????
 
My lathe is the same. Bad design I guess but you get used to it eventually.
 
The lathe I learned on in school was like this. You get used to it but it is a pain.
 
The normal directions for cutting are towards the headstock and from the outside to the centre thats why it can be done this way without altering the direction of the feed screw.

What you are asking is to do a normal lengthways cut and then a reverse facing cut thats why you have to reverse the feed screw.

J
 
Facing should be from the outside toward the lathes axis.
 
I just checked my SB heavy 10 and if the feed direction is toward the chuck the cross feed will be inside to out. I was thought to cut inside to out and that is what the South Bend manual says. I only rarely cut from the inside out I almost always start the cut outside.

I never really noticed as I do not use power feed very often hand feed is quicker for me.

Dan
 
Every lathe I have ever run had that same feed configuration.

It's a fail safe when you think about it.

If you are intending to take a cut toward the chuck and pull the feed handle
the wrong direction, the tool will feed away from the face of the part rather
than plow into it.

If you were intending to face the end of the part and pulled the lever the wrong way,
The tool will feed back from the part rather than plowing into it.

If it were the other way, bad things would happen.

Rick
 
rake60 said:
If it were the other way, bad things would happen.
Rick
Click to expand...

I guess that's one reason why my new to me Standard Modern 1334 has so many marks on the compound slide / toolpost holder! Feed is in radialy or towards the chuck and out radially or away from the chuck.

Mike
 
ninefinger said:
I guess that's one reason why my new to me Standard Modern 1334 has so many marks on the compound slide / toolpost holder! Feed is in radialy or towards the chuck and out radially or away from the chuck.

Mike
Click to expand...

Most of the big machines that I ran during my professional career were built in other countries.

One of them was very clear.

The rapid traverse position had no words on it.
It just had as engraving of a bird.

The feed direction for that handle had an engraving of a snail.

Even I could figure that one out! :)

Rick
 
Philipintexas said:
WOW! I always heard the opposite. It sure seems counterintuitive to do it that way.
Click to expand...

I'm scratching my head wondering if we're thinking the same thing ....what do you find intuitive about it because imo its the opposite.

there's lots of practical reasons for it, but the big one would be how do you start the cut if say you want to take 100 thou off? can't do that easily starting from the centre if there's no bore. next would be clearance, think of how much more clearance (like a boring tool) you'd need facing from axis outward; that's a pita to grind and weakens the tool. Then there is tooling...a hss bit with a big chip breaker ground at the end is the facing tool, cheap and will really hog...you have to use those from outside in.
 
I have always wondered why my instructors at school said to face from the inside out when as pointed out it works better to face from the outside in.

We are talking about making a cut with power feed and figure 73 in "How to rum a Lathe" by South Bend shows cutting from the inside out. Well the picture shows the tail stock center in use. If I was using the tail stock for a facing cut under power I would cut from the center out because you are simply looking for trouble to face towards the center.

Dan
 
Dan Rowe said:
I have always wondered why my instructors at school said to face from the inside out when as pointed out it works better to face from the outside in.
Click to expand...

its one of those funny things, being doing it for so long one way, and with some tangible reasons for it, until this thread came up it never occurred to me to face inside to out.

Not hitting the tailstock centre is good explanation of the one photo; I wonder where your instructor was coming from or if there are reasons for that haven't occurred to me? It will work for light cuts, but I'm not seeing any reasons for it being preferred. Every lathe I'd owned faces out to in as the default, without reversing the feed. oh well, one is not 'wrong' I suppose if it works, but should be aware of the advantages of the alternate
 
I'd hate to try the inside to outside with insert tooling you would just chip the edge off the insert.

The only time I'm likely to do it is when machining a flat bottomed bore.

J
 
The most interesting thing is that there are so many opinions on something I always took for granted. Seems like there's more than one way to learn something. I can see the wisdom of some opinions but also see the same explanation could cause a problem. For example, I generally turn a diameter for a set distance toward the chuck, flip the control lever and face out to finish a shoulder. If I do that now I ruin the diameter, as the feed will be into the finished diameter. I'll learn to do it differently, it's just that being different from my other lathes, I'll have to unlearn some habits.
As for facing direction, I think some new tooling does make more sense facing in vs. from center out, but somewhere, buried in my subconscious brain, was the admonition against facing inward. Fortunately, it's a hobby and mistakes are seldom irreparable.
Thanks for all the input.
 
I read somewhere that outward facing could result in a better surface finish. Of course there needs to be hole of some sort at the center for the tool to start in. My Monarch's crossfeed is quite short, so generally in-out facing is hard to set up and not worth the effort. If you have a rear-mounted cutoff tool then you would want to feed toward the front as well.

I do have to operate the feed/face knob when switching. There's a position in between the two that engages the separate leadscrew for threading.

My own tendency is to power feed facing all the time, and turning up to near the end, except when roughing. I always feed manually when parting.

For the final facing of a shoulder I normally just manually feed outward.
 
If I have a hole in the part, I face from the inside out because I get a better finish. I suspect this has more to do with my lack of tool grinding ability than anything else.

I don't use the power feed when facing very often. Most of the time the diameters I deal with are too small to worry about it. When the part is big enough to warrant power feed, I still find I get a better finish if I do it by hand since I can very the feed rate to keep a more constant SFM at the cuter tip. that being said, my facing surface finishes are never all that good :rolleyes:
 
I have faced many parts from the inside out, but ONLY on a light finish cut.

Turning should be with tool pressure toward the chuck whenever possible.
Facing should always be OD to center whenever possible.

However: For a fine finish from a facing operation, it is much better to take
your light finish cut from the center out.

The nose radius of the tool will "ride up" slightly and in effect burnish the surface
more than cut it.
The finish will be excellent.

Rick
 
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