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This is driving me bananas?! Have I lost my brain?
I can not get this rosewood rosette to stop smearing rosewood all over my spruce. I’m French polishing
I have:
1: used shellac on just the rosette
- smeared
2: used shellac to seal around the rosette and soaked it in thin ca glue then scraped
— smeared
3: painted shellac on just the rosette
- smeared

Help is much appreciated ... I’m running into fear of overworking the area

Thanks
B


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Well, you pretty much outlined everything I would have done. I'm quite surprised the thin CA didn't set it in stone. Sorry, I got nothin.


Wait, are you sanding after sealing?

I scraped it down after sealing w the ca bc it wasn’t smooth:/


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Lord knows I'm no expert, but here is what I do when I have rosewood next to spruce.

First, and foremost, put the CA glue in a locked box, ask someone you trust to hide the key from you, and resist the temptation to buy another bottle. Yes, there are people who successfully use CA in proximity to spruce and get it to work out, but I know I am not one of those persons, and I don't like to tempt fate. You were lucky if you didn't get some permanent staining from the CA. Just avoid it for soundboard use.

Have you tried brushing shellac onto the rosewood with a small artist's brush, separately brushing shellac onto the adjacent spruce with a different artist's brush, and then repeating these two steps a lot until you get what you feel is a good seal coat on both the rosewood and the adjacent spruce, but applied separately? If I had the trouble you were having, that's what I would do. But again, I'm not an expert.

Some carefully brush on lacquer to seal before French polish shellac. Everything should be scraped or sanded or whatever to be just where you would start to finish. Then you get a tiny brush and take your time with the lacquer. You do not sand the lacquer back. The slightly raised area should blend in as the French polish builds.

The only lacquer I have on hand is EM6000 and some spray can nitro from stewmac :/


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Go buy a spray can of Zinsser bulls eye shellac and "mist on" several light coats to seal the rosette (you can lightly coat the whole soundboard to keep things "even"). then carefully apply the next few coats of french polish until you have enough built up to where you won't cut through the previous seal coats.

The alcohol in shellac will pick up the rosewood color, so expect the first coat to be contaminated. Additional coats can also dissolve existing shellac and pick up some of the rosewood color from it, but it mostly happens when you agitate an already wet area. The initial contact will lay down clean shellac while the existing layer is still hard. A little rosewood color may diffuse into the new layer before it dries, but not very much. So carefully shellac the rosewood, let it dry, and then carefully shellac it again, trying not to touch the same spot twice. And since this one seems to be particularly troublesome, do a third coat for good measure. By that point you should have at least one good coat of uncontaminated shellac on the surface, which won't bleed from a quick rub over it.

This is one of the things I did... I’m not sure why but it immediately created a pool or rosewood color that ran everywhere I thought it would work ha
Good idea though.


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Denis, perhaps I’m not allowing the seal coat to dry properly. I’ll try again with a thicker cut having less alcohol and let it dry a few hours before doing another coat

Guys thanks for the help. I’ve never had this issue before... probably because I’ve been using em600 as a finish and a seal


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The trick is to just "Mist" the coats on and let them dry in between. If the shellac created a pool then the coats were too heavy. I guess I should also state something I do, I didn't think to mention. When doing this I have the part being sprayed "flat" so the finish won't run when lightly sprayed.

This issue was on the forum a couple of years ago, but perhaps, the reverse,i.e., lacquer on the purflings to protect them from the rosewood. Anyway, I think someone mentioned to just use clear fingernail polish (comes with the brush). I think another option is polyurethane varnish. Really, just any clear finish that will not damage your rosette and will not dissolve in alcohol. Test whatever you have around on scraps. I am inferring that you do not want to journey into the zombie apocalypse to buy anything right now.

Clear fingernail polish is essentially nitrocellulose lacquer in a small handy bottle.

I got it done with several layers of thicker shellac
The high alcohol content was the issue


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CA should do it, but you have to leave a thin coat on the surface.

The way I do it is; I seal the area that will have the rosette, with vinyl sealer or shellac, depending on the final finish type. Then cut the channel for the rosette and set it using CA. After scraping it flush I lightly sand the area to remove the sealer. Then make a small pad with paper and kind of polish CA onto the rosette only. Then just proceed with the finish.

_________________
Joe Beaver
Maker of Sawdust

B I feel your pain. I have a box under construction which is the first time I have used Rosewood. I cut the bindings of the sides. Just putting a coat of shellac on the top drags the colour off the Rosewood like nobody's business! I couldn't believe it. I have had to sand off and start again on several areas of the top. It's not completely clean even now. OK now I know you always move from the top to the bindings and not the other way, and always look at your pad to see if it is coloured. But still. Maple never gave me this sort of grief!


I guess your experience does tell us one thing. Don't use Rosewood in a rosette!


Dave