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I’ve darkened the color of my shellac by adding dye. I’m quite satisfied with the new color.

I have a piece brushed with several coats of the same shellac flakes without dye, and i thought i’d be able to move expertly enough to apply new darker layers over it, evenly. Is this a futile enterprise?

I’m at two coats of the darker stuff, but new layers are fusing too deep, and shades are melding.

shellac blend
Click here for larger image

Is there anything i can try before getting back to the wood (sanding or spiriting away)?

(before: making shellac darker)

ww_init_js
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    Yes you can do this. Did you expect to nail it first time? ;-) You've only tried this once, it may simply be a matter of practice. Although you might find it works best to scrape down to the wood surface and build again you should play with the variables to see what might help — scuff-sanding the dry shellac, thinning the new shellac more (regularly helpful with shellac application issues of many kinds), softer brush (taklon artist brushes are great for brushing shellac if you're not already using one), padding instead of brushing etc. FFR if you had spray equipment this would be a doddle. – Graphus Feb 20 '19 at 08:28
  • not sure what i expected, but the N previous coats produced good results faster. darker is probably less forgiving. knowing this is possible is very encouraging however. I’ll try thinner coats (than 1lbs cut). i tried a common paint brush and hake brush, i’ll lookup the taklon ones, maybe they soak up less. a doodle would certainly be nice — i’ll keep pads and spray stuff in mind for now. – ww_init_js Feb 20 '19 at 08:50
  • "but the N previous coats produced good results faster" Lighter or sort of neutral colours are the easiest to apply because streaks (and they are some) aren't that noticeable because the contrast is lower. The darker the finish the more and more visible unevenness is. IME with darker shellac like button polish or brown varnishes multiple thin coats are the way to go as each subsequent coat evens out the inconsistencies and builds towards a uniform colour. If you haven't yet, try the tinted shellac on bare wood so you can see how it works without the influence of the previous shellac layers. – Graphus Feb 20 '19 at 16:24
  • Re. spraying, seen any YouTube videos of someone using toning lacquer from a rattle can? Dark-coloured shellac will work pretty much the same. – Graphus Feb 20 '19 at 16:26
  • Hey, just watched this vid from Ross Taylor on YouTube yesterday and there's something in it that's directly relevant to what you're doing. Link, the part you want is from about 7:00 onwards. – Graphus Feb 27 '19 at 16:40

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Some finishes, especially catalyzed ones, will be impervious to further coats which will build up in layers. In other finishes, especially solvent based ones like shellac and most lacquers, the solvent in subsequent coats will dissolve the underlying layers to some extent depending on several factors.

I doubt you will achieve layering your different tones via brushing; brushing prolongs the contact time and offers some agitation, both of which encourage the new layer to mix with the old. The best way to achieve this tonal layering would be spraying thin coats under warm conditions. When I do "wash coats" of shellac on guitars the coat will be dry to the touch in seconds.

I'd say, lacking spraying capacity, you are best off removing the existing finish and applying coats of only one tone.

bpedit
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