Rob
I feel a few comments need to be made in the light of developments on this thread and indeed with the menace of Sawmillcreek looming in the background.
Firstly I would like to thank you for taking such a huge amount of time in preparing your testing and subsequently posting the information here on the Forum. I do know how long this takes and how much effort is involved.
Sometimes I think we, actually all of us, forget that this Forum is a facility for discussion. It would be hopeful to think that all out comments are going to be favourably received, but I do believe we have a right to expect some civility. My perspective is that all your testing has been performed with integrity foremost in your mind.
It does seem to be very unfortunate that some people are so blunt in challenging findings. I have noticed that it is a very prevalent trait amongst the "cousins." Don't worry: Australians can be blunt too and the Woodwork Forums have had their fair share of stoushes!
As to the testing itself I do see an inconsistency with the apparent hardness of the plates and the ability to file them. I remember being told in carpentry to measure several times and then step back and see if it looks right. If it still doesn't look right, measure yet again. If we need a difference of RC15 between the plate and the file, something may not be quite right with the findings as that would indicate a maximum of RC50 for the sawplates.
However the relativity may still be there between the plates. I am assuming that any discrepancy is the same for each plate. Consquently the plate that came up with a low hardness is still an issue even if the value itself is incorrect. I'm not sure if I have explained that satisfactorily.
Not everybody is set up to conduct laboratory style testing. Readers must accept that testing is available at a "entry level" basis. I think it is up to you regarding publishing names. In these times where litigious activity is a profitable sideline for many, I would be keeping such information under wraps until I was sure I could back up statements. It is not quite the same as if you buy a power tool and it fails (smoke escapes from the motor for example).
Again, you have my thanks for attempting this testing and enduring what must have been a very trying and disappointing time. I am a registered member of Sawmillcreek, but I have never posted there and in truth rarely visit: Normally it would only be if a link is provided. I am afraid that attitudes such as displayed on that Forum are not conducive to interaction. I doubt I will be inclined to contribute there until such time as the culture changes, but I am not anticipating they will miss my presence :rolleyes: .
Regards
Paul