RAW neck burnishing - a theory

[Phaedrus]

Alright - Check this out!

Just finished burnishing, and it looks great! BUT, I found something out which is quite interesting:

So I got from the store with 400, 500, 600, 800, 1000, 1200, 1500 and 2000 grit.
Started with the 400 on the back of the head stock- just to see how it is and it was FAST. I mean seriously fast! so I do the neck and it feels amazing and move on to the next grit and the one after and for some reason- it got less fast.
When moving from the 800 to the 2000 there is improvement, but for some reason the 400 still feels smoother (I kept the head stock at 400 for comparison).

On the 400 the wood looks real raw, where in the 2000 it does look finished (anyway it's great looking). But the feel is what got me really puzzled.

So here's my theory - tell me what you think.
From my little knowledge (none) of physics I believe that friction has a lot to do with the surface contact. To some extent our contact with the wood is only at the edges of the particles of the wood. Microscopically the surface would look like this- ^^^^^^, where the grit determines how "big" the parts are.  meaning that on a 400 grit we'll have let's say two "peaks" on a surface where as in the 800 grit we'll have four. every "peak" is another contact point = more surface = more friction.

So why does the 400 feel smother than the 220 that the neck comes set as?
Because our skin is not a complete flat surface, and it takes to some extent the form of what it is pressed on. so a very low grit has such "bumps" in it that stops it. but once these bumps are taken care of (400 grit) - the more you go up the scale- the more surface you create.
So why does the 2000 feels smoother than the 800 still?
I have two guesses:
1) Placebo. A tough one to accept but possible.
2) a switch in "roles". When the surface is so smooth - now you fingerprints become the relevent "peaks" (instead of the shape your skin takes), and now the finer the grit- the easier it is for it to move.

So, have I got you guys tired by now?
Has anyone experienced with really comparing the grits one to the other side by side?

The one problem with my test is that the head stock is flat, while the neck isn't and it harms the "purity" of the comparison. It might not affect at all, or it could be the whole difference Perhaps on my next build I'll check it out (;

 

[Nightclub Dwight]

I haven't burnished a neck yet so I can't comment specifically on that, but necks with a glossy finish will often feel sticky to the hand when you start to sweat a little, while satin (or raw) necks often feel substantially less sticky. 

Another example is with bicycle tires.  I used to run slicks on my mountain bike when I used it to commute on pavement, and the slicks gave much better grip than a standard bicycle tire with a tread.  In this case it is because the slick has much more rubber in contact with the road, while a tire with a conventional tread has points that might not be in direct contact with the road, but might grip better through water or dirt.

So yes, your idea does make some sense.

 

[Cagey]

Makes sense to me.

 

[TBurst Std]

Isn't that also part of the liking for Wenge? Less surface area.

 

[Tele-me about it]

Don't forget to take into account the AMOUNT of skin contact. I'f you're just running your fingertips over the headstock, but moving your whole hand over the neck, there's going to be much disparity in the amount of skin contact and pressure.

However, if you did indeed test each the exact same way, feel free to ignore the preceding.  :icon_tongue:

 

[Phaedrus]

haha just the thumb, but good thinking!
I like a good analysis.