ID cutoff tools and madness!

[vectorwarbirds]

Same guy that tried to drive me mad with the undersize 1/4-28 tap also gave me these but they don't fit my any of my holders. Can anyone ID these? Probably have to buy some big $$$ holder and if that is the case and anyone has a holder I will send them to you. Now I really kind of think the guy is messing with me.

Also FYI some people across the big pond are trying to drive me mad as well. I spend a good part of the morning trying to figure out why the small grinder didn't work, then remembered the KISS program and checked the power cord only to find a itty bitty fuse holder in the plug end! That's it on the right in the pic so just a heads up.

[old mart]

Your best chance is if somebody recognises the number 20 on them, it will be the grade, and each manufacturer uses a different system. There are at least 4 big names that use inserts that look like that, but they are not interchangable.

[tomato coupe]

They look like standard GTN-3 or GTR-3 inserts. Very common.

[J Tiers]

I have the reverse..... holder but no more inserts. May as well toss in the bin when the last insert gives up.

What you have is scrap carbide (unless you know what it fits).

[vectorwarbirds]

They look like standard GTN-3 or GTR-3 inserts. Very common.

Thanks TC I think you nailed it! Now I can buy a holder for them.

[old mart]

If they don't fit a GTN3 holder, at least you will have no problem getting inserts for it.
Here are some pics of GTN inserts, see if they are the exact same shape.

https://www.ebay.co.uk/itm/174713129...8AAOSwmjZgY~Fm

[Illinoyance]

The ebay inserts are not the same as the mystery inserts. The mystery inserts have a shoulder.

[Doozer]

I will say that the Shars paper catalogue does explain cut off inserts very well.
And other inserts too. I highly recommend it.

-D

[old mart]

The ebay inserts are not the same as the mystery inserts. The mystery inserts have a shoulder.

Thats what I feared, there are several very similar things made by the big boys who like to keep their tooling proprietry. The grade number is the best chance of narrowing it down.

I found an advert with parting inserts with a 20 on them.

https://www.kbctools.ca/catsearch/14...2IC20%22%5D%5D

[Bented]

Have been using insert tooling for 30+ years.

Never take the last insert out of the packaging and discard the package, this tells you who made it and what it is (-:

[vectorwarbirds]

If they don't fit a GTN3 holder, at least you will have no problem getting inserts for it.
Here are some pics of GTN inserts, see if they are the exact same shape.

https://www.ebay.co.uk/itm/174713129...8AAOSwmjZgY~Fm

These SP300 / NC3030 inserts are the same shape as the ones I posted earlier but are taller and they do not interchange. I have the holder for the SP300 / NC3030 inserts but not one for whatever the others are. I don't particularly want to buy holders just to guess it out. I've got enough stuff like that already!

[vectorwarbirds]

Thats what I feared, there are several very similar things made by the big boys who like to keep their tooling proprietry. The grade number is the best chance of narrowing it down.

I found an advert with parting inserts with a 20 on them.

https://www.kbctools.ca/catsearch/14...2IC20%22%5D%5D

I believe Tomato and you have nailed it down, GTN inserts. At 20 bucks each and more where they came from I will buy a holder for GTNs instead of throwing them out, well honestly I wouldn't throw them out as I can't bring myself to do that, so drawers of stuff I don't use. Thanks much yall!

[JoeLee]

Thats what I feared, there are several very similar things made by the big boys who like to keep their tooling proprietry. The grade number is the best chance of narrowing it down.

I found an advert with parting inserts with a 20 on them.

https://www.kbctools.ca/catsearch/14...2IC20%22%5D%5D

That looks close, I was going to say valenite.

JL.....

[old mart]

Another thing that could be a clue is the shrink packing, if they were from one of the big boys, they would be in a box, that makes me think they could be GTN.

The NC3030 is a Korloy grade.

https://www.mcctcarbide.com/jv/resou...e-grade-chart/

[Bob Engelhardt]

Before I invested in a holder that the insert might not fit, I would just braze an insert on a piece of CR. My name is Bob and I'm an HSM'er