Learning to sharpen HSS lathe bits......A lesson in futility.....

[Runs With Scissors]

Why abandon triangular inserts? These are cheap - MSC is not

SHARS 5/8" X 4-1/2 RH MTAN INDEXABLE TURNING TOOL HOLDER TNMG NEW !] | eBay

Model# MTAN R-10-3B. TNMG 331 DM YBC252 w/ Finishing chip breaker (PART #424-1731) /. TNMG 331 EM YBC202 w/ Finishing chip breaker ( 424-1769) /. TNMG 432 DM YBC252 w/ Finishing chip breaker ( 424-1735) /.

www.ebay.com

No sir, I am not abandoning that.

I totally believe you about using "cost effective" bits.

I basically 'shot my mouth off" before I finished watching that video

I was just trying to "decode" which tool holder to get for my machine.

Stay tuned.......I'm still watching that video.

 

[DustyRusty]

Slow watcher, slow learner???

 

[Runs With Scissors]

So I have some questions about the choices for the characters.

I need help in filling in the 3 blanks

M-------- pin and clamp
T-------- Triangular inserts
_---------Need help this one (tool holder style.....lots of choices and I haven't a clue)
_---------need help here too. ( Rake angle positive, negative, neutral......again no clue)
R--------Right hand tool
08------1/2 inch square. (this is the biggest my QCTP will accept)
_--------Need help here too (
A--------4 inches long


MT ? ? R08_-?A

in the background of @TheOldHokie post, I see a 1/2" version of what he sent me


https://www.ebay.com/itm/3003527608...brand=Shars+Tool&_trksid=p2332490.c101224.m-1


but that is a

Model# MTAN R-08-2A

• Shank Size Square: 1/2"
• Overall Length: 4"
• Insert I.C: 1/4", T: 1/8"

So that is a negative rake, and the IC is 1/4 not 3/8......Big deal or not?

 

[TheOldHokie]

So I have some questions about the choices for the characters.

I need help in filling in the 3 blanks

M-------- pin and clamp
T-------- Triangular inserts
_---------Need help this one (tool holder style.....lots of choices and I haven't a clue)
_---------need help here too. ( Rake angle positive, negative, neutral......again no clue)
R--------Right hand tool
08------1/2 inch square. (this is the biggest my QCTP will accept)
_--------Need help here too (
A--------4 inches long


MT ? ? R08_-?A

in the background of @TheOldHokie post, I see a 1/2" version of what he sent me


https://www.ebay.com/itm/300352760812?_trkparms=amclksrc=ITM&aid=1110006&algo=HOMESPLICE.SIM&ao=1&asc=271845,271023&meid=27de54f8fa7a4390b54a032771ed274f&pid=101224&rk=4&rkt=5&sd=300517030246&itm=300352760812&pmt=0&noa=1&pg=2332490&algv=DefaultOrganicWebV9BertRefreshRankerWithCassiniEmbRecall&brand=Shars+Tool&_trksid=p2332490.c101224.m-1


but that is a

Model# MTAN R-08-2A

• Shank Size Square: 1/2"
• Overall Length: 4"
• Insert I.C: 1/4", T: 1/8"

So that is a negative rake, and the IC is 1/4 not 3/8......Big deal or not?

That will work but I consider it pretty light. You should be able to find a tool block with 5/8" slot to fit your tool post. Or you can always grind a 5/8" down to fit a 1/2" block.

You are in the learning/experimenting phase so I would suggest you dont spend a lot up front.

Dan

 

[Yooper]

It was so easy when I first got into this game. It was generally triangular and square inserts. Negative rake tooling was just starting to come into its own. I can’t keep up with all the different shapes and geometry and where they each shine. I’ll take a few pictures of what I use on my lathe and pass this on to you.

 

[Runs With Scissors]

It was so easy when I first got into this game. It was generally triangular and square inserts. Negative rake tooling was just starting to come into its own. I can’t keep up with all the different shapes and geometry and where they each shine. I’ll take a few pictures of what I use on my lathe and pass this on to you.

Thank you. I appreciate it.

What rake angle do you suggest?

 

[woodman55]

Gotcha!

Well i found a video that seems to explain how to "decode' the "alpha-numeric soup" of tool holders.

The guy seems to know what he is talking about and so I took his logic and came up with a tool holder number of

MCLNR083A

I made some assumptions on how to massage the numbers..........like going with a 08 instead of his example of 12 and went with A instead of B, in order to find a tool that will fit my machine.

Low and behold the inter-web kicked back a holder that might be what I am looking for?
https://www.mscdirect.com/product/details/05696711
https://www.mscdirect.com/product/details/05696711

Any thoughts?

great video, I have watched some of his videos before. He seems quite knowledgeable. I don't own a lathe, I just like watching stuff being made.

 

[Yooper]

Oh man! That is a very good question to which I have forgotten through the years. I will post a link to a conversation on Practical Machinist that may or may not enlighten us to help answer this.

Choosing Rake Angles for Carbide Inserts Material and Machining Considerations? - Carbide Inserts | Carbide Turning Inserts | Carbide Inserts Manufacturer/Supplier - Apple Carbide Tools

The choice between a positive and a negative rake angle […]

applecarbidetools.com

I’ll post pictures in a couple of days of what I use. Couldn’t get it done today or tomorrow because I am retired and my days seem to be taken up by other peoples plans