Proper sharpening of Hammer flail knives.

[powerscol]

Sharpened my Maschio Giraffetta hammer flails the other day using my hand held grinder. I kept the bottom flat and put a 45 bevel top side. I was very careful not to get them too hot. I also replaced two hammer after I had sharpened the rest. I am not sure but the new knives appeared to have a double bevel (top and bottom) It was hard to check due to the huge amount of paint on them. Cutting went great for about 10 acres, but after going through a few vole piles (loose dirt) the dulled quickly, so I resharpened everything again (flat bottom and 45 top knife edge. The vole piles actually stuck to and piled on the blades (vibration increased as well as power to run). I found the hammer knives to be fairly soft metal.

Now I know Leon will rag me about not using my wet grinder, but the bolts are just to much pain to undo. Maybe this winter I can get to it.

But my question is how should they be sharpened and what angles?

 

[radios1]

maybe you made the same mistake that people make on rotary mowers.. don't sharpen past the thickness of a matchbook cover doubled up. and run the edge past the wheel to make sure it's all the same width.. you don't want something super sharp, that will only wear down too quickly.. next time you're in a store, look at the edge of mower blades, THAT is what you want, a flat leading edge about the thickness of 2 matchbook covers..

 

[Industrial Toys]

My hammer knives cannot really be sharpened. The material get's quickly larger away from the edge. At least not if you are trying to fix up nicks or damage.

As far as sharpness of blades go. There is debate about that with some claiming that OEM blades are not sharp only for reasons of safety.

 

[radios1]

My hammer knives cannot really be sharpened. The material get's quickly larger away from the edge. At least not if you are trying to fix up nicks or damage.

As far as sharpness of blades go. There is debate about that with some claiming that OEM blades are not sharp only for reasons of safety.

only people that don't compare how long the OEM sharpened blades last as compared to a sharpened blade, then the debate is proven moot!..

 

[Industrial Toys]

I guess a guy could sharpen blades both ways and see which edge lasts longer. I have bought Commercial blades that were VERY sharp.

 

[radios1]

I guess a guy could sharpen blades both ways and see which edge lasts longer. I have bought Commercial blades that were VERY sharp.

I have done that already, and found that copying the original grind lasts longer. you make it too shaarp, and the nicks in the blade win..