Hard Turning with no Feed Marks


To All:
I missed this when it first came out, but here is a way to hard-turn
bearing & seal OD's and the like. Here are some excerpts from an
article in MMSonline (short video at site).
=========================================================
formatting link

Hard turning can reduce, and in some cases eliminate, finish grinding
operations. Because it is a single-point turning process, however, it
will produce feed marks on a part?s surface no matter how much the feed
rate is reduced.
Sumitomo Electric (Mount Prospect, Illinois) has developed a
"lead-free" tooling system...
The keys to this lead-free turning process are tool design and feed
direction. Single point turning feeds a cutting point along the lathe?s
Z axis?longitudinally down the rotating part. Conversely, lead-free
turning moves a wide, blade-like insert tangentially across the part in
the X axis. A dedicated toolholder provides the proper lead angle for
the insert as it traverses across the workpiece.
=========================================================
Reply to
BottleBob
Loading thread data ...
formatting link
I have a 6 gallon crock I been putting this kind of shit into for nearly 3 decades now.
Obviously it still leaks
Reply to
Brother Lightfoot
BL:
You saw the video? It looked like a pretty slick idea to me. Have you ever tried it?
Reply to
BottleBob
That's pretty interesting. FWIW, I have a book here from the 1930s that shows a tangential cutter (made of HSS) that has the same purpose. But this one is fed conventionally in the Z axis, rather than plunged.
Reply to
Ed Huntress
BottleBob wrote in news:yNSdnZfEDO5rYZzWnZ2dnUVZ snipped-for-privacy@earthlink.com:
It's also called "Skiving" Bob. Been doing it for decades in cast iron grooving operations.
Reply to
Anthony
Humbug!
Anybody who's ever spent any time around automatics will recognize this as just a new twist on a VERY old technique call a shave tool. New materials and machines make it possible to do this with hard stock instead of just 12L; but a traditional shave could do profiles, gooves, spherical OD's, and then some.
And, properly used, it would let you hold sub-one-thousandth tolerances on machines that couldn't position within +/-.005.
Everything old is new again.
KG
Reply to
Kirk Gordon
You know, the jargon of machining has changed all around over the years, but a skiving tool used to be a form tool that worked with no top rake and, often, with no relief. It was just plunged into the work slightly below center, which gave you a negative effective rake and, effectively, it allowed a bit of front clearance below the cutting edge.
This tool looks more like a shaving cutter, although the geometry of just plunging it into the work looks a little weird to me. The shaving cutters I've seen generally travel along the length of the work.
Reply to
Ed Huntress
Yep, Even on one my old Davenport's I could hold tolerances like that.
Reply to
why
Exactly what I was going to say Anthony but thought it might have been a UK term not used in the US. Well it is in the "Slacking Off" meaning! Does seem though that it's a term that will create puzzled looks these days.
My late mentor used to use the process a lot for fairly complex forms.
Wayne...
Reply to
Wayne Weedon

PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.