Rough surface finish? Try a Vertical Shearing Tool.

[WCraig]

I have a small bench grinder and it took a whole day to grind these tool.

No tool should take a whole day to grind. A coarse grinding wheel that has been freshly dressed should remove metal at a pretty good clip. I wonder if your wheels are too fine or glazed over. And you don't have to worry about over-heating good quality HSS (unlike high-carbon steel). In fact, a wheel that is cutting well doesn't heat up the part nearly as fast as a glazed wheel will.

Craig

 

[homebrewed]

I had concerns about the vertical shear bit's edge breaking down during a long finiishing pass on steel so I ground an M35 blank, which contains 5% cobalt. It took awhile because it was a 5/16 square blank, but it didn't take all day.

Regarding carbide, I have an indexable boring bar that uses a CCGT insert. It can take some pretty fine cuts.

I agree with the comment about staying away from no-name brazed carbide. Awhile back I bought a cheap set of brazed-carbide boring bars and only one or two of them can actually be used as they are. The rest will need to be either re-ground or tossed.

 

[emtor]

My bench grinder is small, 350 watt motor with a 60 grit wheel on one side and 120 grit on the other.
Drill bits are eaten away quite fast but the HSS blanks are a real challenge.
Yes, the wheel glazes and produces no sparks when it does so, dressing with a diamond dresser helps but it takes only a little while before the wheel gets glazed again.
I have a cheap belt sander which does the same thing. After a short while the belt (40 grit) gets dull and stops producing sparks.