I have seen these carbide tipped lathe tools and wondering what they are for. If you look at it from the top it's a perfect rectangle. No cutting angles, no radius on the tip, no rake. There is a little bit of relief though.

I'm sure you guys will laugh at me, but thought it was some type of blank so took it over to the pedastel grinder and tried to put some cutting angles on it. Didn't make much progress. They seem pretty strong.

So I guess I have 2 questions. Can you grind carbide tipped lathe tools? Never really worked with these much, and ones I have used were already a good shaped tool. And the tool I explained, the rectangle shaped tool, what is it for?

Thanks

Yeppers, its most likely a blank ! I worked in a large shop where we often used them to make special tools for purpose. They are grindable but not with the common soft stone. it is best to EDM to form. Altho they have been used in very large manual lathe apps for roughing, the changeable insert has reduced their use.

I have seen these carbide tipped lathe tools and wondering what they are for. If you look at it from the top it's a perfect rectangle. No cutting angles, no radius on the tip, no rake. There is a little bit of relief though. ...

What you might have seen is a tool for cast iron; you can by carbide tipped tools with a variety of tip shapes in grades for steel or cast iron. The steel grade has a slight top and side rake while the cast iron grades are flat.

If you Googled 'brazed carbide lathe tools' you might find some information, or Google KBC Tools or Thomas Skinner & Son

A diamond wheel on a bench grinder will work, just go slow.

Or a green wheel on a bench grinder as a less expensive and not as good alternative.