Sharpmaker = Tip Breaker?

[jideta]

Am I doing it wrong?
I seem to have broken the tips off of a couple of blades, probably at the end of the stroke, while using a Sharpmaker.
Not like the whole tip, but the very end of the point.
Maybe I'm pushing too hard?

 

[Glock Guy]

It’s because you are running the tip off the rods. You need to stop with them in the middle of the rods or you will round the tip every time.

 

[Obsessed with Edges]

The tip breaking has more to do with the hardness & brittleness of the steel itself. With such blades, you need to be very careful with technique on any sharpening media, no matter the type. A very light touch rules, on any media you're using.

Most mainstream cutlery steels properly heat-treated to typical hardness (high 50s HRC) are pretty difficult to break in the first place. If any damage is done, it usually happens by plastic deformation (bending, denting, flattening, etc.), but not by fracturing.

See the pic below. I broke a tip from a ZDP-189 blade (low 60s HRC) when it dug into a piece of cardboard I was using as a strop. Obviously, the cardboard's hardness isn't the cause there. But ZDP-189 is often hardened to extreme levels, favoring edge retention over toughness - so the steel will be more prone to brittleness and fracture, rather than plastic deformation. Any impact on a hard surface like ceramic, or lateral stresses exerted against a thinly-ground tip (as when my tip dug into the cardboard) can snap it off pretty easily, like breaking a thin, delicate shard of glass.

 

[bgentry]

I apologize, I have nothing constructive to say. But I have to post because the title of this thread reminds me of this song SO MUCH. Just substitute the lyrics as:
"You're a SharpMakaa, Tip Breakaa"

Fast Forward to 37 seconds for the relevant part

I now return you to your regularly scheduled sharpening talk...

Brian.