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Mineral spots in Peruvian Walnut

Posted: Mon Mar 26, 2012 11:34 am
by  
As I sand the back, these tiny spots appear. I've tried alcohol, mineral spirits, lacquer thinner, acetone and a spit coat of shellac but the spots remain, smaller than a pinhead but visible from about 12" away. Can anyone shed some light as to how I can cover or remove these spots? Thanks.

tommy

Re: Mineral spots in Peruvian Walnut

Posted: Mon Mar 26, 2012 1:24 pm
by deadedith
I used deck cleaner from a local paint store per a tip from K...uh, another forum.:-)

It's a powder that you mix up with water, slap on the wood, let it rest a few minutes, wipe off with a retarder that you buy at the same time. The paint store guys will know what it is. Oxalic acid stain remover is the product if I'm not mistaken.

Most all domestic hardwoods will have some mineral deposits. And Peru? :-)

Re: Mineral spots in Peruvian Walnut

Posted: Mon Mar 26, 2012 1:39 pm
by tippie53
Often staining will also hide them spots.
it is a pain but part of the game.

Re: Mineral spots in Peruvian Walnut

Posted: Mon Mar 26, 2012 4:00 pm
by Kevin Sjostrand
Tommy,
Just a suggestion....try it on some scrap first.
You need an acid to dissolve mineral deposits. Try some vinegar wiped on. If it is mineral, vinegar will dissolve it.

Kevin

Re: Mineral spots in Peruvian Walnut

Posted: Mon Mar 26, 2012 5:17 pm
by tippie53
kevin got some good advice
take pics and let us know

Re: Mineral spots in Peruvian Walnut

Posted: Mon Mar 26, 2012 5:33 pm
by deadedith
I removed all the mineral spots off a red oak back and sides in 10 minutes or so using the oxalic acid. Just sayin', as long as you don't leave it on a long time (follow the directions), there is no danger of bleaching out the wood.

Re: Mineral spots in Peruvian Walnut

Posted: Mon Mar 26, 2012 6:07 pm
by  
OK, this is quite interesting. Thanks for all the suggestions so far. Have only tried the vinegar but no joy. Will try the other suggestions shortly. Thought I'd share the response to my question I received from Chris Herrod at LMI.

"We've heard that a shellac sealer coat (even a clear
one) will disguise these spots. Aside from that, the most sure-fire way of
getting rid of them is picking the mineral out with a sewing needle.

Best Regards,
Chris Herrod"

-tommy

Re: Mineral spots in Peruvian Walnut

Posted: Mon Mar 26, 2012 6:13 pm
by  
deadedith wrote:I used deck cleaner from a local paint store per a tip from K...uh, another forum.:-)

It's a powder that you mix up with water, slap on the wood, let it rest a few minutes, wipe off with a retarder that you buy at the same time. The paint store guys will know what it is. Oxalic acid stain remover is the product if I'm not mistaken.

Most all domestic hardwoods will have some mineral deposits. And Peru? :-)
Dave,
I have some oxalic and will start with a mild solution and hope for the best. Thanks for the suggestion.
No worries on the K word. So long as he allows you to say it here we are OK with you saying it here. ;- )
-tommy

Re: Mineral spots in Peruvian Walnut

Posted: Mon Mar 26, 2012 10:07 pm
by Ken Hundley
I have had mineral deposits on some woods I have worked with, and left them in. I have sprayed a sanding sealer as a bonding coat, which worked well for its purpose, but did nothing to alleviate the mineral deposits. Where it might work is if the solvent in the sanding sealer causes the oils to leach out of the wood and "cover" the deposit before the coating solidifies.....just thinkin with my fingers.....

Re: Mineral spots in Peruvian Walnut

Posted: Mon Apr 02, 2012 6:43 pm
by deadedith
Tommy - how are you and your mineral spots doing?