Replaceable insert ID questions

ER16 = External Right hand size 16 is 3/8" inscribed circle. I recommend the 16 ER AG60 which is a partial thread insert that covers a wide pitch range. Full thread inserts are a fixed single pitch only, useful if you need very tight precise threading profile, or for difficult threading like ACME threading.

This would be for the external threading right hand holder
This would be for the internal right hand threading holder

I use been using the Carmex inserts with the BMA coating in a wide range of metals, they seem very durable and with 3 cutting tips I keep one in the holder and one as a backup. I get very clean threads, I just knock down the top of the threads with a fine file and one spring pass. If you holder came with inserts, try those, but if you are not getting clean cuts or the inserts break, I would try Carmex (which is a Iscar brand).

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Recent threading project in marine bronze.
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shoot, problem editing. I inadvertently linked an NPT insert.

Try something like this:

ER16. Make sure the IC fits your toolholder.

GsT
Thank you , im sure this is for another thread but I have no idea what IC is or its application . My short jump into inserts I have seen theres much to learn. Im just looking to so some small projects.

I do not get a lot of time in front of the lathe. I have ground my own HSS but its another project on top of everything else.
 
Thank all,

So it appears im missing the package of ER16 inserts. That was supposed to come with it.
Thanks all
I will be looking into learning more about inserts
 
IC is the inscribed circle, ie the circle diameter that would touch each edge of the insert from the center point of the screw hole. This determines the size of the insert and is standardized. The threading inserts use the metric nomenclature that identifies the length of each size. A 16ER insert has a length along one side of the triangle of 16mm. MKSJ's chart above shows that in drawings above the table.
 
So im on the right track
16ER is the tool holder size ?
So if I wanted to cut 10 tpi RH acme I would order this insert? Just an example
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16 ER is the insert size and type (external right hand), the toolholder part number describes the type of holder as well as its shank size. You have an SER1616, the SER indicates it is a right hand external threading toolholder, the 1616 is the shank size, ie 16mmx16mm. Inch ipsize toolholders would gave a part number SER0625 for a 5/8” square shank. The H16 on the end indicates it take a size 16 insert. Since it looks like you have a Shars toolholder, they print it on the side of it, so that holder uses a 16 ER insert.

The insert you posted above should fit in your toolholder, but it is for a stub ACME, not a standard ACME thread. A stub ACME has a shorter profile. If you wanted to cut an ACME thread, you need an insert that doesn’t have the stub in the name.

Cutting tip is about 45’ off to left
Internal inserts are opposite hand of external, so your internal inserts would need a left hand toolholder to fit properly.

Attached are the complete documents mksj posted above that might help you understand a bit better.
 

Attachments

You know you can grind your own acme tool from HSS. I made a 5 TPI acme tool, actually 2 of them, one from 3/8" HSS, and a second from 1/2" HSS. Both work, but the 3/8" tool only took me 15 minutes to make. (First time I ever ground an acme form.) Really was pretty easy to make. Your thread could have been single pointed by now. Heck, you could have cut ten screws!

Unless you are planning to turn a difficult material, HSS is a good choice. It's mystifying to me to see the majority of folks here shy away from grinding HSS. It's not hard to do, and it beats waiting for inserts to show up. You can grind forms that are custom and unavailable to buy. Dunno, it beats sitting around staring at your empty mailbox...
 
Been using the same carbide insert for multiple years, beats sitting around grinding HSS, then having the point go while threading and then figuring out how to align it after regrinding. I use carbide inserts on a wide range of materials and thread up to 600 RPM, HSS would not last. These days I only putter with HSS for special profiles, old school vs. new school. Otherwise I consider it a waste of my time, we each have out preferences, but for someone starting out, using an insert is one less variable that they need to figure out.
 
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