Carbide insert question

[Dabbler]

@Megar arc 5040dd

Back in the dawn of time (long before offshore inserts were available, I started with a single TCMT tool holder with inserts that were 14$ each (in 1980 dollars)... I used HSS for many operations, and used the carbide for heavier operations on my 750 lb 12X37 Taiwanese lathe. (The holder itself was over 170$ in 1980)

I used that holder exclusively for about 15 years before I bought an indexable carbide boring bar. That one is long gone, but later I lusted for CCMT style turning tools, but waited, and waited.. And bought WNMG tools for my little lathe. The normal inserts will stall my little 1HP motor, but the aluminum inserts cut like a hot knife through butter. Better than my HSS regrinds.

Inserts for aluminum are not cheap, and even from offshore sources can be 6-8$ each. I have yet to dull or break one, but I use them sparingly.

I have recently bought some DNMG tooling, as each type/shape of insert is used differently, and my TCxx and my WNxx styles won't let me do some undercutting operations for turning that I want to do. I sometimes use a HSS parting tool to do them, but I had some tool lust so I went for it.

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Moral of my story/experience: Get one type (not the 4 types in those crappy kits) of better quality (holder from Taiwan or better) and use the hell out of it... It really doesn't matter it it is a Txxx Cxxx Wxxx - all are general purpose polygons. Use up a bunch of offshore inserts, and abuse the heck out of them. THEN buy a few Kinnemetal or Sandvik inserts and change your experience.

 

[mmcmdl]

You know I have boxes full of the good stuff John . See you in July or sooner .

 

[Megar arc 5040dd]

@Megar arc 5040dd

Back in the dawn of time (long before offshore inserts were available, I started with a single TCMT tool holder with inserts that were 14$ each (in 1980 dollars)... I used HSS for many operations, and used the carbide for heavier operations on my 750 lb 12X37 Taiwanese lathe. (The holder itself was over 170$ in 1980)

I used that holder exclusively for about 15 years before I bought an indexable carbide boring bar. That one is long gone, but later I lusted for CCMT style turning tools, but waited, and waited.. And bought WNMG tools for my little lathe. The normal inserts will stall my little 1HP motor, but the aluminum inserts cut like a hot knife through butter. Better than my HSS regrinds.

Inserts for aluminum are not cheap, and even from offshore sources can be 6-8$ each. I have yet to dull or break one, but I use them sparingly.

I have recently bought some DNMG tooling, as each type/shape of insert is used differently, and my TCxx and my WNxx styles won't let me do some undercutting operations for turning that I want to do. I sometimes use a HSS parting tool to do them, but I had some tool lust so I went for it.

------------

Moral of my story/experience: Get one type (not the 4 types in those crappy kits) of better quality (holder from Taiwan or better) and use the hell out of it... It really doesn't matter it it is a Txxx Cxxx Wxxx - all are general purpose polygons. Use up a bunch of offshore inserts, and abuse the heck out of them. THEN buy a few Kinnemetal or Sandvik inserts and change your experience.

That is one part I never really considered, does the tool holder make that much of a difference? Aside from boring bars where they are sticking out so material can make a big difference in rigidity. In a regular tool holder for outside turning does material and quality make that big of a difference? After all it is already a short rigid setup to begin with. I had always considered making my own tool holder as a fun small project is this something that is not advisable? Is it the material that makes a cheap tool holder not good or is it more the finishing and the fit of the insert? I got so hung up on the inserts them selves that I never really gave much consideration to the tool holders.

 

[Susquatch]

That is one part I never really considered, does the tool holder make that much of a difference?

I'll take the view that it usually does. In fact it can make a BIG difference. Or sometimes I find I think I wasted some money.

My own approach was to start with the insert I wanted and then go find the tool holder for that insert. (sometimes that left me with no options but to pick another insert.)

I like @Dabbler's advice to just get something and run the crap out of it. Then once you feel you are comfy, go get something better. Makes good sense to me.

Prolly cuz we each have some work we do more than others do. So what is the perfect tool for one guy isn't the right tool for the other guy.

 

[Dabbler]

does the tool holder make that much of a difference?

Most of the cheap offshore holders are ... cheap. the material isn't heat treated, so the threads are soft, and the seats for the carbide wear out quickly. I'm still using the original Kinnemetal tool holder I bought 45 year ago.

The better ones from offshore are fine for hobby use: Taiwanese or the higher quality Chinese ones are fine.

All steels have a very similar stiffness - it defies 'common sense'. but 4140 at Rc 40 will have a similar deflection as at Rc55. One grade of steel will have a little better stiffness than others, but that's another thing all together.

The most important thing is how the tool holder wears at the insert seat, and the thread longevity. A tool steel holder, properly heat treated will last a lifetime. A soft tool holder might last a year or 5...

Having a carbide anvil will extend the life under hard use, and will save the holder from damage if the insert breaks.