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I haven’t built in a while and to get back into it I decided to use this EIR set that has randomly shaped light splotches on both sides of the back. I got this set for free and this guitar is really just for practice, so I’m more focused on working on technique than ending up with the perfect looking guitar. So this flawed set seems perfect for this build.

Having said that, I’m curious if you guys know what the cause of this is, and if there’s any way I can add a finish to this wood that will allow the grain to show without the splotches. I tested out a few dye mixtures on what will be the inside of the guitar and that didn’t work. Everything darkened, but you could still see the imperfections clearly. If I can’t find a solution I’m just going to spray an opaque color on it. But if I could learn a new finishing technique to hide these imperfections then I’d really like that.

I look forward to hearing everyone’s thoughts.



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I’ve read that you can take acetone and wipe colour from the rest of the back onto the light parts. Never tried it though..

If that didn’t work I’d just leave it...

Not sure of the cause, minerals or insects most likely.

To get around them I would use wood bleach and bleach all the rosewood and then use a wood conditioner followed by a stain to bring it back closer to the original color.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

That is mineral deposit in the wood. I think it's a form of calcium. Try blotting some vinegar on it, sometimes it can dissolve the calcium. CLR cleaner can work also.

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Guitar Maker and Purveyor of the World's Finest Tonewoods
http://www.aaronhixguitars.com/
http://stores.ebay.com/A-Hix-Tonewood-a ... r-Supplies

I’m going to give that a try, thanks for the recommendation! I’ll let you know how it goes.

Beauty spots

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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.

tried many things found CLR to be the most reliable stuff to use

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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

So I rubbed a lot of vinegar on the spots and couldn’t get them to disappear. Maybe it’s because they go all the way through the wood (they are on both sides). I think this guitar is going to have to get an opaque finish, which will be good practice for me anyway.

If an opaque finish is in that guitar's future, I would give some serious consideration to Brian Howard's suggestion first. If it doesn't work you can always go opaque.

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Joe Beaver
Maker of Sawdust

Sorry, I missed that suggestion before. Does anyone have a link that goes over bleaching rosewood? I did some quick Googling, but didn't find anything regarding bleach type, process, etc. Some people mentioned that it might break down the wood's cellular structure and weaken the wood. Would there still be distinct wood grain after bleaching and staining, or would it mostly be one color?

Muriatic acid diluted 50/50 has worked for me. Afterwards, neutralize the acidity with a wipe of baking soda. Experiment on scrap cutoffs, if you got 'em.

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

Following up on this, I tried both vinegar and two rounds of CLR with no effect on the spots. I even tried scrubbing them with a toothbrush. Whenever I get the wood wet with water, naphtha, or mineral spirits, these spots seem to absorb the wetness differently than the rest of the wood.



On this front, I first tried two rounds of oxalic acid with no effect. I have also done two rounds of two part wood bleach. While the wood has lightened, the splotches have gotten even whiter. The splotches seem to absorb the bleach differently and quicker. I wonder if these spots will always show or if I can get this wood a consistent whiteness and then dye it back. I will keep trying, I just hope this wood will take a finish when I’m done with all this. I try to neutralize the wood as I go along but I have really put a lot of chemicals on this wood.