I have not sealed by Nakayama Asagi as it is mounted to a wooden base. My Kiita came sealed. I use clear nail polish on the stamps on my naguras...
Most lokely, It wont bother anything, but you can lap the sealer back when you get close to it.
Frank the way I see it, you will chamfer the edges if you get that close so no touchie the sealer.
I sealed the wrong side of one of my nagura (no maintenance when drinking!) and it came right off with the DMT.
People traditionally seal jnats because they're layered stones that can absorb water between the layers, or if they have a crack or fissure on the side. Getting water in a crack was a problem in the olden days when you left your hone in the tool shed and it froze at night.
I doubt you need to seal any novaculite.
Cheers, Steve
Charns can loose pieces at the edges and sides. Sealing one that could be prone to that sort of thing is probably a good idea, esp if you're traveling with it.
Idyllically, you'd want to use a sealer that penetrates into crevices and pores and whathaveyou - not so much one that just sits on top. A thinned out brushed on lacquer would be advantageous over one that sprays on I think.
Ahhh - Nitro, love the stuff. It is interesting stuff but difficult to work with, hard to get sometimes and it's prone to crazing also. Great for a 59 Gibby but maybe not so much so for a Jnat. The last time I used Nitro it was to antique the grille cloth on a rebuilt blackface Bassman. I've done whole guitars with it too, but not in a verrrrrrry long time. Last one was a 60's SG... all black. Miss that axe....
Done, with brush on lacquer (mods, I'm not gonna hijack this into a Charn thread) :-
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