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Any creative methods for removing white calcium deposits from Rosewood pores? I usually have to loosen them with a small needle or knife blade and blow the powder loose with compressed air. Have not had much luck with air alone. A little tedious if there are a lot.
Thanks
Terry

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Sharpie.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

Terry, I find these in Mohogany ocasionally as well and have been using a nice stiff wire brush. Not too course as to remove wood but fine and strong enough to catch the minerals and "rake" them out. I tried tooth brushes but they were not agressive enough ( and my wife kept wondering why her toothbrush was turning purple? ) . A lot of mahogany necks have these calcium/salt/mineral deposits and if they are not addressed they show up under finish and look bad.

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jw ( o)===:::

Every time I think that I got away with something like this I fail to wonder why the toilet in my bathroom was so very clean all the time and my toothbrush was wet..........

I am a Sharpie guy too, safer than risking a brown toothbrush.......

Thanks guys. The sharpie is a good idea. Black I assume. I figured the Ca compound was probably a strong base so I tried a weak acid (vinegar) but it didn't work too well and changed the color of the wood a little. Did HCl work pretty well for you Todd? I figured a strong acid wouldn't work as well to dissolve a strong base.
Terry

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It's not what you don't know that hurts you, it's what you do know that's wrong.

I think I've run into this on a mahogany neck. I'm finding tiny white specs embedded in the pores all along the length of the neck--far too many spots to successfully pick out with a needle. Neither light sanding nor naphtha have helped, so I want to check that I understand the muriatic acid treatment before giving that a try. Let's see if I have this straight:

1) Dilute the acid by half with water
2) Apply the diluted acid to the targeted areas
3) Scrub and rinse thoroughly with distilled water

That seems simple enough. Is that it? Any advice would be greatly appreciated.

Thanks,
George :-)

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George :-)

You can do what Larrivee does... leave them. I've got a mahogany guitar with them all over the place. If you are using colored pore filler does matter?

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Jeremy Douglas

Jeremy,
Thanks for the reply. I like to pore fill necks with a slurry of sanding dust and shellac and I don't know if that would address this issue or not. I guess I could give it a try and see what happens. Larrivee leaves the deposits visible? Hmm... I guess it could have a certain organic appeal, but I'm not sure I'd like it all that much.
Best,
George :-)

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George :-)

Well I have a all mahogany Larrivee with white deposits in the pores, I'm not fond of it either. Maybe they take steps to remove them on the higher end models or just try to avoid using wood with the deposits, I don't know.

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Jeremy Douglas

Jeremy, I've never seen anything like what I have going on here in a finished guitar. Maybe we're talking about different things?

Anyway, if anyone can offer some support about the hydrochloric acid wash, or any other approach to this situation, it would be very much appreciated.

Here's a pic of what I'm seeing:



Thanks,
George :-)

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George :-)

I don't think so. You'll probably have to click on the picture and zoom in to see the deposits but they're there. The white deposits aren't on the neck, top or back so I'm pretty sure it's specific to the wood used on the sides.

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Jeremy Douglas

I would be reluctant to "spot treat" areas, thinking that I'd rather get whatever residual or side effect occurs over the entire piece.

That's $0.02 from someone with a bunch of fine woodworking experience, and VERY little luthier experience, so take it more as an educated guess.

I will be facing this issue in lutherie when I get to some of the "opportunity grade" EIRW in my stack.

Dennis

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Dennis Leahy
Duluth, MN, USA
7th Sense Multimedia

Dennis,
Poor wording on my part. Yes, assuming I use this procedure, I do intend to treat the entire back of the neck evenly.
Thanks for your reply,
George :-)

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George :-)

I've never heard of anyone using dilute hydrochloric acid to remove deposits from porous woods before but I have heard of using it to dissolve cellulose to manufacture rayon or cellophane so I'd be very sceptical about trying this. Now given wood is principally cellulose I can see a nasty end to this.

If you're determined to try this, remember:
1) Always add acid to water
2) Wear eye protection and nitrile gloves
3) Don't wear any clothes that you're not prepared to have holes in (At university we could spot the people who regularly did lab work from the pinprick acid burns in their jeans).