View Full Version : Threading inserts

10-18-2011, 11:16 PM
quick question,

What are the beneficial differences between a full form threading insert and a partial form insert? they both cost about the same, just wondering what you all recommend? thanks

10-19-2011, 01:55 AM
If you're asking about laydown inserts: partial form will do a range of threads (but none completely correctly), full form will do only a single thread but form the thread crests and valleys correctly (but no other TPI). If you single point threads occasionally I'd go with a G or A inserts (as in 16ERA60), if you're cutting a single thread a lot then use the full form (as in a 16ER16UN). Full profile is nice since you can just thread until the major diameter is 'right' (counting the crest) and the thread is usually dead on.

10-19-2011, 07:33 AM
+1 to what rkepler wrote.

The partial profile inserts, 16ERA60 or 16ERAG60 (for example, but there are others) are great to start with because you can make any thread between 8 to 48 pitch (AG) or 16 to 48 (A).

I started with those. I've since added full-profile pitch-specific inserts as I go along. I mostly buy two at a time, though a couple of really amazing bargains have given me packs of 10 that should last me 14 lifetimes.