What causes different feedback when chopping?

[JaVa]

Hats of for doing the test Kippington. It's been a lot of fun to follow the progress! :cool2:

Still My heads spinning. In the alternate universe that I live, it's puzzling to me how two pieces that not only have a difference in hardness, but also differ in dimensions and still share the same tonal characteristics. That's astounding and super cool at the same time.

I'd be brave enough to suggest that in the light of the results, would it be fair to assume, that if the you make a mono steel W2 knife and a knife with the W2 core steel clad with the mild steel tested here, that the mono steel knife would vibrate more of the two and provide more feedback?

Or am I too quick to draw?

 

[Nemo]

Hats of for doing the test Kippington. It's been a lot of fun to follow the progress! :cool2:

Still My heads spinning. In the alternate universe that I live, it's puzzling to me how two pieces that not only have a difference in hardness, but also differ in dimensions and still share the same tonal characteristics. That's astounding and super cool at the same time.

I'd be brave enough to suggest that in the light of the results, would it be fair to assume, that if the you make a mono steel W2 knife and a knife with the W2 core steel clad with the mild steel tested here, that the mono steel knife would vibrate more of the two and provide more feedback?

Or am I too quick to draw?

This is probably a reasonable hypothesis but in complex systems like this I think you actually have to run the experiment to be sure. There are potentially a lot of variables affecting the outcome, and we don't really know which is important. Finding out which is important by experimentation is of course the basis of scientific thinking.

And thanks Kippington for running the experiments. It's been fascinating.

 

[malexthekid]

The problem with third test is that there is no control. There may be an external factor affecting results and without a control to use as a baseline that may be skewing results.

Still interesting.

 

[Kippington]

Yeah thanks guys, it was a fun test to do!

I'm honestly still surprised by the results. From the beginning I could pick up one of the tiles with my eyes closed, ring it, and I always knew which piece of steel I was holding despite the fact they were indistinguishable to me in shape, weight and texture. This always remained constant throughout heat-treating.

...the mono steel knife would vibrate more (than the clad knife) and provide more feedback?

I initially thought incorporating the mild steel (which vibrates more) into a knife would cause it to vibrate more. But you're talking about them damping each other out, yeah? That does make sense to me.

The problem with third test is that there is no control. There may be an external factor affecting results and without a control to use as a baseline that may be skewing results.

How would I utilize a control in this test? Come to think of it, I didn't see a control in the paper posted earlier in the thread (I might be wrong).

...it's puzzling to me how two pieces that not only have a difference in hardness, but also differ in dimensions and still share the same tonal characteristics.

I'm guessing the dimension change was so slight that if it did have an effect on tone it was too small to tell. That might be another experiment for another time!

The interesting thing about hardness is that it measures something beyond elasticity. I mean, the machine that does the test itself has to make sure to bypass any elasticity before it even begins its measurement. On the wiki for the Rockwell scale:

• 
  Operation
  
  ​
  The determination of the Rockwell hardness of a material involves the application of a minor load followed by a major load. The minor load establishes the zero position. The major load is applied, then removed while still maintaining the minor load.

So basically the vibrations happen within the confines of the minor load, before the machine has even established a zero position (bypassing elasticity/Young's modulus) for measurement of the major load (hardness).

 

[malexthekid]

How to utilise a control is for this experiment out of my skill set.

For something like this you need to produce a sample which you can predict the result to make sure it is all working perfectly. Not saying it isn't just you can never discount it unless you have proved it.