Beginner Question

Logan Novice

Logan Novice

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Not exactly a beginner hobby machinest, but new enough not to know everything I’d like to and I have a question that’s been bugging me for quite some time.
I see adds on various forums listing lathe tools and components with the leading “CNC” xyz123”

CNC collet, CNC chuck, etc. Far as I can tell, except for he fact that it’s computer controlled, a CNC lathe’s tooling is pretty much the same as my little manual machine. So what am I missing here? Is there something special about a CNC collet that I need to understand?
 
Randal and John are correct, IMO.

Disregard the CNC nomenclature. Buy what you can use.

There are considerations when buying used things, like collets, from a CNC shop. IMO there is a good chance it's been rode hard and put up wet.
Collets and nuts (and many other things) are considered consumables in many (most?) production shops, so zero time is spent on their preventative maintenance. For instance, I have bought used collets where the slots were fully packed with tiny swarf. Degreasing didn't remove the debris. I had to clean out the slots with a razor blade. having those slots packed solid has to diminish clamping force, my guess is that's why they sold it off rather than spend their valuable time cleaning. I've also bought a few used collets that had bores that were ruined, so junk for my purpose.

If you're talking about new merchandise, Buy what you can use.
 
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I'm sure there is a marketing component to this - especially in any of the free-for-all type places like ebay or amazon.

However if you look through the catalogs of the companies that sell to manufacturing and production shops, a lot of the stuff that's designated "CNC" is specifically designed for high volume / automated production. Time is money, automated machines run as fast as the can be run etc. So any cutting tools mills, drills taps etc - have features and designs that make them well suited for feeds and speeds way beyond what you are going to do with a small, manual bench mill or even most mills that the typical hobbyist will have. Some of the roughing mills are useful and might work better - but again a lot of them do not offer any advantage at lower spindle speeds and hand cranked feeds, or they just won't do the job on a really light cut that your machine can handle.

Other stuff like CNC vises or hold downs may or may not make sense for you - depending on what you are doing. A low profile vise designed to be used in gang setups on a CNC mill bed, might be just what you need. However there are likely better more versatile options that are cheaper.

I ended up getting a a 1/2" shank ER11 or ER16 collet "chuck" really a holder, the shank is about 4" long and it has a low profile collet nut. it really is designed to let someone use these small collets in a bigger CNC machine where the reach (4" shank was the shortest) and clearance (low profile nut) can be an advantage. I also got a set of collets to go with it - have a tiny desktop CNC machine that uses the same collets, so I can now use a variety of drills in it. The spindle on the desktop CNC tops out at 24K RPM.

The 4" shank chuck is not for my CNC, it allows me use the same collets in my bench top mill with a half inch mill holder AND it also in my Deckel D-bit grinder so I can handle a wider range of shank sizes (sharpen drill bits etc.). I work with small stuff so it made sense.

If I didn't have the Deckel and the desktop CNC my precision drill chuck would be just fine for my mill.

The collet holder with long shank was marketed as "CNC" ER11 collet chuck.

I am by no means an expert on this stuff and I'm still learning. When I was just getting started, I stuck to the most common cheaper "traditional" manual tooling - figuring that I had much more to learn before trying more exotic stuff.

So use common sense, don't spend more than you need to (there's always more to buy!)
 
Marketing!
Tooling for "real" CNC production machines is expensive and worth it's price to a manufacturer running the machines at maximum out put.
A cutter with runout wears much faster at the high rotational speeds and feeds used in industry. The more runout the faster the wear.
With runout, one side of a cutting too will be doing more work than the other, increasing wear. A worn cutting edge has more heeling action and therefore heats more. The hotter a tool runs the sooner it gets to the breakdown temperature. Vicious cycle. All that horse power being put into the cutting action needs to be dissipated as mostly heat. If the geometry is good, much of that heat is carried away by the chip and not put into the tool.
 
There are some tools that require extra effort to use on a manual machine. Or have something that is specific to CNC devices. Mostly, as above, a marketing gimmick. Rarely it actually means something to think twice about, especially pricing.
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Often drill chucks are sold as CNC due to the fact the drills are clamped by a tool. An example is a keyless drill chuck should never be used on a CNC as it is not clamped by a tool. Sometimes by a C spanner, allen key or wrench.
 
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