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Greetings from Montana. I thinned my intended redwood soundboard too much and am looking at another set I have. I'm wondering about these white spots. Lots of research yielded little. My only guess at this point is salt efflorescence. This set came from California and is supposedly forest salvage. Salt from the ocean? I'm not saying they are uniformly through the sample but are present on both sides and both pieces. I assume these deposits will affect finishing. What about tone?

Any ideas or further research tips would be greatly appreciated.

Gary Davis

Look like mineral deposits.
If it is ocean salt deposits water should remove them, so I would try that first.
If it's mineral deposits, see video https://www.youtube.com/watch?v=PGF0FohKcE8&t=88s
But you must test it outside the plate outline you're using it, and don't use a wire brush on redwood.
Apparently it's not uncommon in domestic redwood https://www.lmii.com/blog/2016/05/08/dealing-with-mineral-deposits-may-2016/ where it says they may disappear under shellac which is easily tested on an offcut/spare bit.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

OK - thanks for that. I did try some water yesterday (and sandpaper). Not much happened. I'll give it a better shot next time I'm at the shop.

If its salt, I'm assuming it would taste salty or would that be a dangerous thing to do-to taste it?

Gary

how thick is the top?

Is it thick enough to sand it down without messing it up?
3/16 is fairly normal for suppliers.
sand with a palm sander in a spot that will NOT be in the guitar shape.


Mike

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Mike Collins

Muriatic acid has worked for me on EIR with white spots. Might be worth a try, though it's nasty stuff. Take precautions.

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formerly known around here as burbank
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http://www.patfosterguitars.com

CLR us what I use to remove mineral deposits.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

OK y'all. Thanks. I may get a chance to go over today. I'll report what I find.

Gary

I checked it out a bit more yesterday. There are just too many spots. Water seemed to do nothing. I'll just get another set - hopefully without spots.

Any recommendations for acquiring another redwood soundboard?

[[url][url=https://flic.kr/p/2oaQmtQ][/url]Untitled by Gary Davis, on Flickr/url]

Gary Davis

I have bought some good sets from Vince Strauss https://www.pacificcoastwoods.net/.

Did you try CLR as per John's recommendation, or only water?

Thanks, M

Only water. I'll try the CLR.

Gary

This sinker set had some white spots, but they pretty much disappeared when coated with shellac.


Pour a pool on it and push it around so it can really soak in before it dries. The initial shellac application makes a big difference to the appearance. If the initial coat is done with a fairly dry cloth, it will create a thin film just on the surface and prevent further coats from penetrating. Useful for preventing endgrain from darkening, but in this case we want to see if the mineral spots go clear when fully wetted. And deeper penetration usually looks better on soundboards anyway.

Felly Smith at Fiddleback Woodshack in Bend, OR is a good source for nice redwood tops. He doesn't have sets posted on his website right now, but he's going been doing several runs of very nice redwood tops and posting about them as he does them on Instagram. I think they've been selling too fast to be worth putting up on his website. I recently bought several sets from him. If you contact him, he'll send you photos of top sets that are available. Felly's a good guy to deal with.

http://www.fiddlebackwoodshack.com/products.php?id=2

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Thanks Jay. I've acquired a few pieces from Fiddleback. I'll contact him.

Thanks for the images Dennis. I think I'll get another set and experiment with this one. I'll mix up some shellac.

Gary