What's wrong with my threading technique?

[Cenedd]

Meh, if you only use stuff for what it was intended, you'll never get anywhere!

[txfireguy2003]

Nope. Cenedd got it right. In post 202 txfireguy said that it was in a similar but different holder when he got it, but he broke that holder.

Not exactly. Their were two similar holders and two inserts, both assembled, in this little cardboard box. No matter though, I've destroyed both inserts and one holder, so I'm moving on to greener pastures, and tools that I know are correct and I've proven to myself that I can use. I'm going to limit my use of the previous owner's tooling unless I'm 100% sure of its purpose, such as standard turning inserts and holders.

Sent from my SM-G892A using Tapatalk

Life's rough, and then you die....

Yes, I can imagine it is. I couldn't do what you do so I give you credit.

[J Tiers]

40 of those are yours.

Life's rough, and then you die....

Thanks for caring enough to count..... I think you missed one.

Buried in 224 posts? OK.

40 of those are yours.

[J Tiers]

Buried in 224 posts? OK.

[danlb]

OP stated that it was like that when he got it, and likely you are right about it being a turning tool holder that has been re-purposed badly b y the previous owner.

Nope. Cenedd got it right. In post 202 txfireguy said that it was in a similar but different holder when he got it, but he broke that holder.

I could be totally wrong as I didn't purchase it directly. It was assembled in a small box with a similar holder that was neutral rake angle (flat on top) which I broke when I first started trying to thread stuff a few months ago. It was my fault, can't remember what I did exactly, but it was no fault of the tool's.

[J Tiers]

OP stated that it was like that when he got it, and likely you are right about it being a turning tool holder that has been re-purposed badly b y the previous owner.

[Cenedd]

Okay, here are some pics from this afternoon: This is the tool I was trying to use.

Not sure if it's of help or if I'm just stating the obvious but those inserts look like TNMC inserts which are supposed to be used "on-edge" like that but the holder I've seen seems to - as suggested - have the top of the insert level.
I wonder if that holder is maybe for an ordinary TCMT and you're just holding it on-edge when it should have the insert on top.

Edit: correct insert code.

[Cenedd]

someone please correct me if I'm wrong

It'd be churlish of me to complain when Tomato Coupe did MattiJ. I had seen that the third letter is about tolerances - which is far more relevant to repeatability in close-tolerance CNC work than in a home shop - but haven't seen the lesser-spotted sharp CCMT or dull CCGT in the wild. I'm hardly shopping the high end of inserts though. More than five bucks a piece and I'm already getting twitchy!

[MattiJ]

I've got plenty of normal CCGT inserts for cutting stainless, and lots of sharp CCMT inserts designed for cutting aluminum. The "G" vs. "M" designation is not about sharpness.

Yeah...but never seen anything else than light finishing inserts for (stainless) steel in CCGT form (pretty sharp too but not as sharp as alu CCGT inserts)

Like I said it's USUALLY better than 90% proof identification of aluminium or sharp(ish) steel insert even if in theory its all about tolerances.
I guess no point of grinding the inserts at factory unless they need to be somewhat sharp and once you go at trouble grinding them you might make them G-tolerance as well.
Milling inserts are bit different as the size tolerance is more important.

[tomato coupe]

Like Ceneddd said: "usually"

While what you say about tolerance is correct in theory in some ways you could say instead of usually "almost always": Try finding "dull" CCGT insert or really sharp CCMT insert.

I've got plenty of normal CCGT inserts for cutting stainless, and lots of sharp CCMT inserts designed for cutting aluminum. The "G" vs. "M" designation is not about sharpness.

[Cenedd]

Cheers Danlb - looks useful. Will have a read up.
Tomato coupe: noted, thanks. Was confused by only ever seeing the G's for sale as alu profile.

[MattiJ]

The difference between a CCMT insert and a CCGT insert is just the size tolerances. You can buy both in various grades for different materials, as well as "sharp" versions for aluminum.

Like Ceneddd said: "usually"

While what you say about tolerance is correct in theory in some ways you could say instead of usually "almost always": Try finding "dull" CCGT insert or really sharp CCMT insert.

[tomato coupe]

You'll find that a CCGT is usually a sharper insert for aluminium ...

The difference between a CCMT insert and a CCGT insert is just the size tolerances. You can buy both in various grades for different materials, as well as "sharp" versions for aluminum.