I am trying to work with a titanium rod using hhs tool bits but they seem to dull very fast and wont cut anymore than about .005 at a time. Can anyone give me some info on what carbide indexible cutting bit is good for titanium? Im thinking of buying a set but not sure of which type is best for this.
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Which carbide indexible cutting tool is best for titanium?
- Thread starter WarrenP
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Can you give specifics on the part and material. Lets talk about the stock size and grade of titanium. What machining operations? (drilling, OD turning, boring, etc.) What quantity of parts will be made?
Titanium will workharden very easily. We tried to use similar tool geometry as for cutting aluminum. High positive rake, higher feed rate than steel, lots of cutting fluid. Heat from cutting does not come off with the chip.
You also need to watch for built up edge material, it kills the carbide quicker than anything else.
You also need to watch for built up edge material, it kills the carbide quicker than anything else.
It is a 1.5 inch rod I am trying to turn down to about an inch diameter. Not sure off hand what grade it is. Jut general OD turning. HSS works but I have to keep sharpening it over and over. Thanks for your responses.
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This ↑ . I use high positive alumn specific inserts for Ti. CCGT, DCGT, CNGG, TCGT, SCGT. They do well for me & last me a while but I'm just a hobbiest & do not work in high production.
Seco and Sandvik make excellent insert tooling for titanium and other heat resistant alloys, Inconel, Monel, Hastelloy and like materials.
Look there first and you will likely find what you require.
There are other manufacturers but these are 2 that I am familiar with.
Look there first and you will likely find what you require.
There are other manufacturers but these are 2 that I am familiar with.
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If you want a low cost starting point, try a CCMT OD turning tool holder (SCLCR) and a CCGX insert (Shars.com is a good place to get these from). The larger the nose radius, the greater the required depth of cut and cutting forces, but the better the finish for a given feedrate. A small nose radius will provide tighter tolerance cutting due to reduced forces and allow you take a smaller depth of cut which might be a requirement for your lathe. See how long those last.
The CCGX has polished top face and a quite positive geometry. Because they are ground on the periphery, they are very sharp and tend to do well in soft gummy materials. Cutting oil or coolant are a must as the built up edge will quickly destroy the insert. The insert will cut well at any speed, however you will get the greatest productivity and tool life when running at the Mfg. suggested surface footage (aka. spindle speed). with such a small diameter, this recommended speed may be well beyond the capabilities of your lathe.
If you find that these insert wear out too quickly (not breakage, that's a different problem), then you might want to consider talking to a tooling specialist like Sandvik or Kennametal. They know their products and can recommend a tougher grade of insert probably with a coating to do the job you want. Expect to pay significantly more for this insert.
The CCGX has polished top face and a quite positive geometry. Because they are ground on the periphery, they are very sharp and tend to do well in soft gummy materials. Cutting oil or coolant are a must as the built up edge will quickly destroy the insert. The insert will cut well at any speed, however you will get the greatest productivity and tool life when running at the Mfg. suggested surface footage (aka. spindle speed). with such a small diameter, this recommended speed may be well beyond the capabilities of your lathe.
If you find that these insert wear out too quickly (not breakage, that's a different problem), then you might want to consider talking to a tooling specialist like Sandvik or Kennametal. They know their products and can recommend a tougher grade of insert probably with a coating to do the job you want. Expect to pay significantly more for this insert.
These are shapes, they do not describe the actual insert edge geometry or material that it is made from nor any coating applied.
Any CCMT insert will fit in a CCMT holder regardless of what material the insert was intended for.
I happen to have 2 inserts on my desk right now, they both fit in the same tool holder yet have wildly different geometry and coatings. the one on the left is very negative rake with a large edge radius, (this is not to be confused with nose radius), this one has a TiN coating and is excellent for roughing steels.
The one on the right has essentially zero rake and a sharp edge, I do not know what the black coating is called but it works well on aluminum and other non ferrous materials, also plastics when they have never been used on any metals, including CPVC and UHMWP.
In other words the insert "shape" does not determine the usability of a given holder for a particular application.
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Agreed, so long as you stay within the basic shape and size. A holder for a CCMT32.xx will also fit a CCGX32.xx or a CCGT.xx, or a variety of other similar geometries, but can't be used for say a WNMG or DCMT insert.
Also I might be wrong on this but don't negative or neutral rake inserts require special holders which tip them on a small angle, while positive rake inserts use a flat holder? Thus a CNMT and CCMT insert could not be used correctly in the same holder?
In the modern world the rake can be produced at the insert edge, in the photo above you may notice that the insert on the right due to its geometry is essentially a positive rake insert held in a negative rake holder. The plane of the tool is negative yet the cutting edge is 0 or slightly positive.
This is why the lands are concave.
This is why the lands are concave.