Official Luthiers Forum!

Well, the subject line tells most of the story, and the question is... will anything eliminate or reduce the effect of slight yellowing in a spruce top? I'm thinking bleach, hydrogen peroxide, etc. Has anyone found a solution that will work?

TIA,

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Ken Mitchell
Durham, NC

Alas, I don't think there is a solution. Yellowing from CA glue happens when the glue is sucked into the end grain of the spruce. The yellowing is not on the surface of the wood. You could sand all the way through and not get the yellow out.
Any chemical that you would use to bleach it out would have to follow the same path as the original glue did but that path is no plugged up with CA glue.

I've had this problem near the center seam next to the sound hole.

Thanks, Mike. I was afraid that would be the answer

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Ken Mitchell
Durham, NC

sunburst

If you use a little amber (vintage look) in the finish it won't make it disappear but it will be far less noticeable.

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Joe Beaver
Maker of Sawdust

A larger rosette?

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

Don't use CA where it can get on/into the top

After having numerous problems such as this, (I learn the hard way sometimes) I have taken to a wash coat with shellac.

It's not bad... hardly noticeable, actually, but I hate not having something 'right'. BTW, I have been using shellac as a sealer, and this happened anyway. Maybe I didn't let the shellac dry long enough...

IN any case, amber or some type of burst is sounding like an interesting idea... and a learning opportunity - HA! (That's what we otherwise call 'errors', right?)

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Ken Mitchell
Durham, NC

A sunburst is your best way out. I had this happen once and I could see it under the amber, although much less obvious.

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Jim Watts
http://jameswattsguitars.com

Right you are! By the time I had my discoloration blended in (pretty well) the color of the top really sucked I thought, I should mention that the stain was yellow with a slight green tint to it. Then again I don't really do sunburst and such so it could of easily been my inexperience with good shading technique.

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Jim Watts
http://jameswattsguitars.com

Hi,

I have the very same problem on my current build, and it pisses me off...
It's the last time I use thin CA for gluing rosette purflings!

Q.

Well, the yellowing is not showing up very well in my iPhone pics. It's worse than in the pics, but they are not "terrible" stains.

I'm wondering... what about a few coats of amber shellac, to the entire top? I always use several coats of shellace before my top coat anyway... Plus I'm shooting water based lacquer, and would feel less confident about tintint it (if it's even possible?).

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Ken Mitchell
Durham, NC

As per several suggestions here, I've put a couple of coats of 'blond' shellac on the top, and I like the color so far. I probably should have used amber, but blond seemed to match the stain. The stain is still noticeable, but a bit less so.

I'm wondering... and maybe someone can answer this: I bought some garnet flakes also (this is my first time using shellac flakes, BTW - I like it), thinking maybe I'd try some sort of shellac sunburst (!)... could I add some garnet to the blond and make a deeper, amber-like color of shellac, if I need to go a little darker to cover the stains?

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Ken Mitchell
Durham, NC

In my experience, you can mix and match any shellac that you dissolved yourself--blonde, garnet, button lac, seed lac--no problem. You could probably add anything you have to the hardware store pre-mixed shellacs as well, but I've never tried that.