"Randy333" wrote in message
...
I need to do some thread milling, never did it before!! I need to cut
2- 1-1/4"-11.5 NPS exteranl threads, a 1-3/4"-16 external and a
1-7/8"-18 internal thread.

I found a thread mill for 11.5 NPS but in the catalog it's listed as
internal only, why? Any place I can get this at under $300 bucks that
MSC wants?

Remove 333 to reply.
Randy

I have never done anything like this either, but I could see that a tool
meant to cut right-hand internal threads would work better for left-hand
external threads than right-hand external (think about the slope direction
of an external thread versus and internal as you look at it from the
cutter's point of view.)