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Michael,

Thanks for posting your test results. As you obviously knew from the start, it's not the final word on the subject, but I think it does give us some useful, real-world information to ponder.

Okay, if someone could take the time for the scientific method, this might work (without hurting guitars, and without their inherent variabilities):

Take identical (as is possible) plates of spruce, identically thicknessed (as possible) and identically prepared. Coat each plate with a different finish, to a standard appropriate for each product. Leave one unfinished. Let them cure an equal amount of time in the same environment.

Set each piece on the same surface, apply the same force to each (preferably with a device or setup that takes human error out of the test), and measure each with the same precision tool (again, that mitigates human variabilities).

I think the above would give us usable information. To make the test purer, we'd have to put the finishes on truely identical, manufactured, surfaces and use hardness testers and/or laser measuring devices.

Whatd'ya think? Anything amiss with my reasoning?

Carlton,
I think it would be an interesting test.

I'm going to avoid being an engineer and try out this naturalist thing. (No sarcasm intended.)
The largest factor is the piece of wood. The ability of a thing film of finish, .010" - .020", to resist dents, at least in my opinion, would be negligible. From the test above, the difference is quite small. You still have a dent.

Would it make more sense to consider which finish is more easily repaired?

_________________
"An adventure is only an inconvenience rightly considered. An inconvenience is an adventure wrongly considered." G. K. Chesterton.

[QUOTE=SteveS]   The ability of a thing film of finish, .010" - .020", to resist dents, at least in my opinion, would be negligible. From the test above, the difference is quite small. You still have a dent.?[/QUOTE]
That's why I thought the original test was valuable. It showed that, indeed, the differences are negligible.

[QUOTE=SteveS]Would it make more sense to consider which finish is more easily repaired?[/QUOTE]
Ha! Shellac wins!!!

Steve's point is from data analysis point of view, scientifically I did not have near enough controlled variables or number of clinical trials to make any kind of informed scientific judgement from. This is the point he keeps trying to dive home. And on this point I must agree with him 100%. However I never intended this to be any kind of a seriously documented trial. I merely looked at it as, "out of these three guitars ((four if you call an ovation a guitar )sorry I am not fond of ovation ) What is the comparative dent resistance between them". I did not measure the film thickness, nor how close the tops were to being the same thickness, nor any other variable outside of controlling the velocity of the impact through free fall at a controlled height with a given mass. I merely rigged a drop stand 3" above the test area of each and released the bar, measured the dent that the bar put into the film. So he is right I just wasted time with this study from an engineering and data annalists stand point. Oh well    

Actually, Michael, I think he's modifying his thinking somewhat. In proving something scientifically, nothing can be assumed. There are a lot of assumptions in circulation about finishes, and you showed that, indeed, the differences among finishes are negligable, at least in this test. Not a waste of time at all!

As Steve wrote, maybe repairability is more important.

Not to speak for you Michael, but I think you were just exploring a way to satisfy your curiousity about a much debated quality of finishes, namely dent resistance, and were hoping to have a conversation about that.

So why isn't anyone Googling whether anyone has ever done this kind of test before?

_________________
"Building guitars looks hard, but it's actually much harder than it looks." Tom Buck

[QUOTE=SteveCourtright]So why isn't anyone Googling whether anyone has ever done this kind of test before? [/QUOTE]

This site explains a test for scratch resistance that could probably be adapted easily for dents. Look at page page two here.

_________________
"An adventure is only an inconvenience rightly considered. An inconvenience is an adventure wrongly considered." G. K. Chesterton.