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Evan
11-05-2004, 12:20 PM
My wife has some NOS ceramic inserts. I cannot find any information on these at Valenite or anywhere else and she has no info either. Anyone know anything about what they are for?

Valenite VC-VCPA 3101 Ceramic .4351C .125 Thick

ERBenoit
11-05-2004, 01:12 PM
My limited knowledge of ceramic inserts,
1.)They are $$$$
2.)They are used for highly abrasive materials, such as cast iron.
3.)They are used for high teperature nickel based alloys.
4.)They contain NO metallic substances in their structure.
5.)They are resistant to heat and wear.

I have never used them. The above information is only what I have learned elsewhere. I have no real idea of what the specific inserts you have are designed for.



[This message has been edited by ERBenoit (edited 11-05-2004).]

Evan
11-05-2004, 01:16 PM
I wonder how they would work for turning off hard anodizing on aluminum parts? In the past I have used a diamond insert for that as nothing else works.

wierdscience
11-05-2004, 10:52 PM
I know the ceramic grades are used for alloys containing %8 or greater silicon,so yes they should hold up to the AOX skin just fine.

The V should indicate a 35*diamond shape
C should indicate a 7* clearance angle
P either is wrong or denotes a special tolerance
and A should be a cylindrical center hole.

How close did I get?

nheng
11-05-2004, 11:23 PM
Evan, I've reworked many small parts with hard anodizing using carbide inserts. Just make sure that your depth of cut is adequate to get to the base metal. A drop or two of tapmagic and slow speed left me with a nice bright finish on the bare aluminum.

After reworking around 20 small parts, each with some threads removed and a small length turned, the insert showed no additional wear, even at the point where the oxide layer "rubbed".
Den

G.A. Ewen
11-05-2004, 11:40 PM
I would try them on different materials just out of curiosity.

Who did Betterhalf bring them in for? There should be someone at the place that buys them who should know what they are for and where to use them.

rbregn
11-06-2004, 12:06 AM
You can cut a timkin bearing with them! They will not handle an interupted cut. They are brittle, but when used with the right speeds and feeds are very usefull. When they are sharp you can turn your dial .001" and it will cut .001" with a excellent finish. They like high rpms.

Evan
11-06-2004, 02:14 AM
My wife didn't bring them in. They have been in stock for ages. Wierd, I haven't actually looked at them but they are used to cut nickel babbit (she just now tells me). I also need to machine some silicon bronze that is extremely work hardened. I expect they will work for that. I can't get high rpms though. What difference will it make on bronze at lower speeds, if any?

wierdscience
11-06-2004, 09:40 AM
Ooooh..well maybe not so good then,they do like speed,seems like they call it dynamic sheer or something like that.Basically in the given sfpm range they are designed for the material is sheared off so quickly that most of the heat is transfered to the chip and not the tool or the workpiece.It may not work at lower rpms,it could cause heating in the insert which on ceramic isn't good.

Of course if they are cheap try it,otherwise if you need to remove anodize I would use a common negative rake insert like a CNMG or CNMA

Tony
11-06-2004, 06:47 PM
ceramic, huh?
you know, i've had this little mixed bag of inserts i got at an auction once.. maybe 10 pieces all told, different shapes / sizes..

they're bigger and lighter than my usual inserts.. dont have holders so i've never used them.. but the have no chip breakers.. they're smooth finish on all sides, just little geometric shapes with a hole in the middle.

could they be ceramic?
if not, what might they be?
they're twice as big as my regular t-carbide inserts and weigh less than half.

-tony

rbregn
11-07-2004, 12:24 AM
Tony
ceramic inserts are lite, they kinda feel like plastic. I like to take one that is chipped and turn a piece of timkin bearing. You don't need the lights on, makes a really cool light show!