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Discoloration in wood

Discussion in 'Woodturning Discussion Forum' started by Marc Snyder, Jun 30, 2020.

  1. Marc Snyder

    Marc Snyder

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    Location:
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    I wonder what these discolorations are and what to do to remove or minimize them, if possible.

    On this piece of horse chestnut there are two types of discolorations or stains, one is greenish and the other is a muddled brown. I have seen the muddled brown on other woods that I have recently turned, including on some ambrosia maple.

    AF2975C0-3B2F-4E9C-8E5C-786294634E7B.jpeg
     
  2. john lucas

    john lucas AAW Forum Expert

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    There are two things that work on some stains but not many. Lemon juice works on some and italic acid on some. Maybe someone else has a solution
     
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  3. Lars Hansen

    Lars Hansen

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    Pardon me for flashing my ignorance on chemestry and/or English, but what is "italic acid"?
    Would that be oxalic + autocorrect =„Äč italic ?
    Lemon juice may have other active components fighting stain/discolorations but I have found pure citric acid useless for this task - great for preventing staining, though.
     
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  4. hockenbery

    hockenbery AAW Advisor Staff Member

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    Lemon juice will remove stains caused by iron. A common problem with maple and other woods. When the iron from the grinder makes black where we touch the wood.
    If the dark area is a fingerprint then lemon juice would work.

    2 part bleach might work.
    It turns wood a lighter shade but it has no effect on black spalt lines or the red stain in box elder - makes them pop.

    color is a great way to enhance a turning with less than top quality wood grain.
    Milk paint is easy... add a few beads or coves and you have the opportunity to show multiple colors by cutting back the top coats to show the colors and wood underneath.
    Airbrush paints offer lots of options too - they can be brushed on.
     
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  5. robo hippy

    robo hippy

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    Well, looks like mold type of stains, and/or what happens when the wood starts to decompose. They go all the way through the wood. I would leave them, or totally cover them with stain or paint. Not sure if even bleaching the wood would help because you would end up with a white piece of wood. I do prefer the natural look of the wood, and those stains are natural...

    robo hippy
     
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  6. Donovan Bailey

    Donovan Bailey

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    Sycamore gets this kind of mottled coloration too. If it can't be sanded out...personally, I just leave it as a natural feature of the wood.
     
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  7. Marc Snyder

    Marc Snyder

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    Thank you for the advice!
     
  8. John Jordan

    John Jordan AAW Advisor

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    Fungal growth. It can occur in a matter of hours when its hot and humid. Even bleach won't fix it-it will change it, but there will always be a contrast.

    John
     

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