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Lets Talk Surface Prep

After reading through the SG20K thread, I started to think about surface prep for different stones. I have personally found finishing my coarser stones, 3K and lower with an Atoma 600 for a nice matte surface and my finer stones with an Atoma 1200 for a nice satin surface to be pretty ideal.

How do you guys like to prepare the surface of your stones, and what do you feel gives the best results?
 
My Jnat and Thuri get the 1200 Atoma treatment. The Black ark receives either 600 or 800 WD sandpaper on a granite surface plate depending on my mood and what available in the shed. I’m scared of killing the Atoma on the hard ark and don’t use it.

My midrange stones just get lapped and refreshed on the 400 side of the Atoma. I find that I get good results like this.

I generally dress the Coticule with the matching slurry stone after lapping. I haven’t had much luck with the Coticule yet. I think that I prefer a sharper finish to be honest.
 
I have a DMT 325 plate that I have had since probably 2012-2014 ish. Been using it for everything and been really happy. I would say sometimes finishing stones will get rubdown with a tomo of some sort but I usually don't notice a difference
 
325 Dmt that I’ve had for 10 years and lapped 100s of stones with, cotis get a rub down with a slurry stone after, Jnats the same.
Tried using an extra fine dmt as a slurry stone and it started wearing away at the base plate so gave up on it

I used to lap / prepare stones to a high finish (1500 wet and dry sort of level) thinking I needed to, and I get better edges now because of better / more consistent technique than I ever did then with my mirror polished rocks

Super hard stones like trans arks I will take to 1000 grit wet and dry if I only intend to use them for finishing.
My take on it is that a finer finish means that there are less pronounced peaks and troughs left behind by the lapping abrasive, this leads to a more consistent contact between steel / stone.
And also the stone is less likely to shed any loose grit as the force applied to the tops of these peaks is lessened, (same applied force to the razor but more evenly distributed)
 
What I have found is that the most important thing is, for each stone, consistency from session to session..
For stone XYZ, it always gets 'finished lapped' to ABC grit using w/d, Atoma, DMT, etc.
For example - my SB Ark is always finished to 600x w/d. I could finish it on 1k or finer w/d but I find that to be a waste of time and counter-productive.

That said, if I did go that route I'd be sure to always finish the stone the same way so the process remains, basically, identical.
Being consistent here allows muscle memory to work efficiently. It is feasible that a stone lapped to a finer degree and used with an extra Newton of force will/may behave similarly as a stone lapped to a lesser degree but used with less 'pressure'.
The point is - everything is relative and one person's sweet-spot does not need to be numerically the same as someone else's.

I lap softer Arks to 'feel' not grit, usually use a 140x plate first and then go from there.
Most Jnats for finishing get a worn 600x w/d finish after a worn 400x Atoma lap. Those on the softer side do get surfaced a bit differently than those on the ultra hard side though. This is partially due to the nature of the stone and partially do to my own use/techniques/applications.

And then, some days, I do everything differently just because I can. No rule, no recipes. Constantly challenging the knowledge base and skill set.
 
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