Preshaped HSS lathe tools?

Perhaps I've overlooking something obvious, but in perusing the MSC, McMaster and Enco catalogs, I've noticed that there do not seem to be any ready-made HSS cutting tools for lathe use. I seem to have a choice between either premade bits of carbide brazed to a steel shank, a holder and carbide insert system, or HSS blanks for grinding custom tools. I expected to find ready-to-use HSS cutters of all shapes and profiles, with a choice of shiny, TiN, TiCN etc.. just as with drill bits, but these don't appear to exist and I'm curious why. Has carbide obsoleted these things, or did they never exist at all?

-Adam

Reply to
Adam
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I saw them in McMaster catalog. Look in later addition or on their webpage. I was surprised when I saw them becuase I have never seen anyone sell preground toolbits before (except sherline and I wasn't impressed with the ones I received).

chuck

Reply to
Charles A. Sherwood

Hi, Adam. There is an outfit that advertises in HSM that sells HSS inserted tools specifically for guys like you. I know a guy who uses them and loves 'em.

Grant

Adam wrote:

Reply to
Grant Erwin

Some of the hobbyist suppliers such as Blue Ridge Machinery used to sell them, but I don't know if they still do. I don't think they were ever sold for industrial use. There is some outfit that advertises in HSM that sells lathe tools designed for HSS inserts. They also sell the inserts. IMHO most serious hobbyists with 6" or better lathes have switched to carbide (brazed or inserts) for normal work, reserving HSS for form ground specialty tools.

Randy

Reply to
Randal O'Brian

The only time I have seen pre-ground HSS tools (other than those which came in an old machinist's chest, where the previous owner had ground them) was in sets for new owners of hobby lathes.

The set of tools in the machinist's chest were an interesting education in what can be done with HSS.

The basic reason for the continued existence of HSS tool bits (blanks) is that they offer the flexibility to grind to *any* needed shape (e.g. form tools) -- and to *re*-grind at need once they get dull, or when you need a different custom shape and no longer need the old shape.

And -- they can be ground a lot sharper than most carbide, especially sharper than tools with TiN coatings. Also, TiN coatings would suffer at the first re-grind. For drill bits, it is not (normally) a problem, because the grinding is on the end, and the primary benefit offered by the TiN coating is a smoother slide up the flutes for the chips. An exception is when you need to "dub" a bit to use for things like brass, where a rake on the cutting edge can draw the bit into the workpiece. But for brass -- you don't need the TiN coating anyway.

I usually use carbide insert tooling in special tool holders, but I do grind HSS for special cases, and I keep a few unground 1/2" cobalt steel tool bits for that purpose. (And I have two Stellite ones for that special situation where the Cobalt steel is not enough.

The most recent home ground tools were a pair of Acme threading tools for inside and outside threads that were just too big for the insert tooling which fits my lathe to handle. The holders for the next size up were too big (and too expensive) for my BXA sized quick-change toolpost holders, so HSS was what made sense -- one in a standard tool holder, and one in a boring bar.

Note that I had to calculate angles for the Acme bits to set them up for a given pitch and diameter. The insert tooling for Acme has a series of solid carbide anvils to go under the inserts to tip them at an angle appropriate to the needs of a given thread to match the pitch angle.

It is worth while learning to grind tool bits, even if you mostly use carbide inserts.

If you really want HSS, and don't want to learn to grind it, I have read of HSS inserts to fit the shanks for carbide tooling.

Enjoy, DoN.

Reply to
DoN. Nichols

Adam:

Chronos in the UK

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sells sets in several sizes. I would check Blue Ridge Machinery in the US as well. I know I've seen them in a US catalog. If you're just getting started, having a set of pre-made ones might be very handy as they will give you a great example of what your tool should look like. The diagrams shown in most books on grinding lathe tools I found very confusing when I was first starting.

My practice is to rough grind them free hand from blanks, and then use a jig to finish grind them to the correct angles. It's not hard after you've ground a few blanks. However, if I could have bought an already ground set starting out, I would have.

George

Reply to
gglines

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