12-30-2013, 02:40 PM
Dave,
I'm very well versed in this technology, so fire away with questions.
For starters, let me offer this. First identify the size of the holders your lathe uses. They must be QCTP or indexing four-sided blacks that hold square shank tools parallel to the ways, as the insert holders and inserts have the geometry built in. There are some 6 different I.C. sizes of the lay down inserts available, though probably up 90% of those sold are the "16" (3/8" I.C.) size shown in my photos above.
The nomenclature for the holders can vary, though inserts are fairly standardized. The two biggest makers are Vardex and Carmex, both based in Israel. Oddly enough, Vardex uses a non-conventional numbering system for the "first" characters. Specifically, where I've stated 16ER, Vardex actually uses "3ER".
That first part aside, the ER means "External", and "Right hand". The numbers that follow describe the thread they make if full profile, or generic angle if "partial profile". I should note that there are also partial profile inserts which fit the holders that can make either 8 to 48 threads per inch, 14 to 48 or 8-14 threads per inch. (Convert to metric if you must, I'm lazy.)
There are external left hand, external right hand, internal left hand and internal right hand inserts.
16EL (or 3EL) - external left hand
16ER (or 3ER) - exernal right hand
16IL (or 3IL) - internal left hand
16IR (or 3IR) - internal right hand
The insert designation following the 16xx is, for full profile inserts, what thread pitch they make. The same inserts are used for each pitch, regardless of diameter. For example, here's a few designations I have in stock:
16ER-14UN (14 tpi Unified National, right hand external thread)
16IR-24UN (24 tpi Unified National, right hand internal thread)
16EL-10ACME (10 tpi Acme, left hand external thread)
I have seen holders for the 16 size threading inserts down to 3/8" square shank, and they work fine.
One of the lesser known features though best benefits of the full profile inserts is that you don't need to use pitch micrometers or thread wires to measure the threads as you cut them. Leave the diameter at "nominal" and let the cresting insert cut the finished outside diameter of your thread as it nears finished size. For example, if I'm making a 1/2"-13UN thread, I turn the blank to .500 (or leave stock diameter.) As I'm cutting the thread I wait until I see the threading insert start cutting the O.D., and when that reaches .494" I know I have a finished 1/2-13UN class 2& class 3 compliant thread.
Ask any question at all. If I don't have the answer, I know where to find it. ;)
I'm very well versed in this technology, so fire away with questions.
For starters, let me offer this. First identify the size of the holders your lathe uses. They must be QCTP or indexing four-sided blacks that hold square shank tools parallel to the ways, as the insert holders and inserts have the geometry built in. There are some 6 different I.C. sizes of the lay down inserts available, though probably up 90% of those sold are the "16" (3/8" I.C.) size shown in my photos above.
The nomenclature for the holders can vary, though inserts are fairly standardized. The two biggest makers are Vardex and Carmex, both based in Israel. Oddly enough, Vardex uses a non-conventional numbering system for the "first" characters. Specifically, where I've stated 16ER, Vardex actually uses "3ER".
That first part aside, the ER means "External", and "Right hand". The numbers that follow describe the thread they make if full profile, or generic angle if "partial profile". I should note that there are also partial profile inserts which fit the holders that can make either 8 to 48 threads per inch, 14 to 48 or 8-14 threads per inch. (Convert to metric if you must, I'm lazy.)
There are external left hand, external right hand, internal left hand and internal right hand inserts.
16EL (or 3EL) - external left hand
16ER (or 3ER) - exernal right hand
16IL (or 3IL) - internal left hand
16IR (or 3IR) - internal right hand
The insert designation following the 16xx is, for full profile inserts, what thread pitch they make. The same inserts are used for each pitch, regardless of diameter. For example, here's a few designations I have in stock:
16ER-14UN (14 tpi Unified National, right hand external thread)
16IR-24UN (24 tpi Unified National, right hand internal thread)
16EL-10ACME (10 tpi Acme, left hand external thread)
I have seen holders for the 16 size threading inserts down to 3/8" square shank, and they work fine.
One of the lesser known features though best benefits of the full profile inserts is that you don't need to use pitch micrometers or thread wires to measure the threads as you cut them. Leave the diameter at "nominal" and let the cresting insert cut the finished outside diameter of your thread as it nears finished size. For example, if I'm making a 1/2"-13UN thread, I turn the blank to .500 (or leave stock diameter.) As I'm cutting the thread I wait until I see the threading insert start cutting the O.D., and when that reaches .494" I know I have a finished 1/2-13UN class 2& class 3 compliant thread.
Ask any question at all. If I don't have the answer, I know where to find it. ;)