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Discussion Starter · #1 ·
My most difficult project in the last 18 months has just one more problem to be solved. I applied Minwax wood conditioner and two different colors of Minwax stain to the dresser top and it looked awful so I stripped it but it still looks bad.

The picture below does not show well the blotchy problem and the parallel wide lines (3 or 4 of them) that run against the grain almost from side to side of the top. The picture may look okay but in person it surely does not look okay.

I am desperate to try to get this to look better. Should I strip again this time more aggressively? Should I use oxalic acid or is that too severe? Since I can't spray if that is the only solution I will have to take this to the only shop in town that can do that for me.

Can’t wait for this one to be over.

Gary
 

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There's a little blotching but most of what I'm seeing you could just call birch. You might be able to save it with dyes if the color is suppose to be the color of the dark spots. Just go over the lighter areas with dye on a rag and blend the color in. If the dark spots are too dark, then strip it and use the oxalic acid. Then when you go back try not to stain the dark spots. If you had the means of spraying you could stain it a little light and use the dye in a sprayer and just shade in the light spots.

I thought of you today. I'm refinishing somebodies kitchen and spraying most of the doors and drawers in their back yard by the pool. The kitchen I just have a portable spray booth fan I sit in the door to vacate the fumes.
 

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Discussion Starter · #3 ·
There's a little blotching but most of what I'm seeing you could just call birch. You might be able to save it with dyes if the color is suppose to be the color of the dark spots. Just go over the lighter areas with dye on a rag and blend the color in. If the dark spots are too dark, then strip it and use the oxalic acid. Then when you go back try not to stain the dark spots. If you had the means of spraying you could stain it a little light and use the dye in a sprayer and just shade in the light spots.

I thought of you today. I'm refinishing somebodies kitchen and spraying most of the doors and drawers in their back yard by the pool. The kitchen I just have a portable spray booth fan I sit in the door to vacate the fumes.
Steve the dark spots are too dark so I will go the oxalic acid route and hope that I can save this.

The refinishing job you were working on by the pool is something that I would never consider at this point.

Gary
 

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Discussion Starter · #4 ·
There's a little blotching but most of what I'm seeing you could just call birch. You might be able to save it with dyes if the color is suppose to be the color of the dark spots. Just go over the lighter areas with dye on a rag and blend the color in. If the dark spots are too dark, then strip it and use the oxalic acid. Then when you go back try not to stain the dark spots. If you had the means of spraying you could stain it a little light and use the dye in a sprayer and just shade in the light spots.

I thought of you today. I'm refinishing somebodies kitchen and spraying most of the doors and drawers in their back yard by the pool. The kitchen I just have a portable spray booth fan I sit in the door to vacate the fumes.
Steve additional stripping and oxalic acid after that made a big improvement in this piece. Hopefully the dye will bring it all together finally.

Gary
 

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Actually, oxalic acid dye is not the thing to use. Pigment stains like Minwax consist of a mixture or dye stains and pigment stain. A little resin (varnish) is added to adhere the pigments to the wood. When you use a chemical stripper, the stripper will dissolve the resin and allow the pigment to be removed. However, the chemical stripper will not affect the dye stain which has been absorbed into the cell structure of the wood.

The process to remove a stain like Minwax Wood Finish is to first apply a chemical stripper containing methylene chloride. This removes most of the pigment color but leaves the dye color. To remove--or at least greatly reduce the color--you need to use a chlorine bleach. The chlorine used in swimming pools will work fine. Apply it and keep the wood wet with more bleach until the color--at least most of it--is removed.

Oxalic acid bleach is used by woodworkers to remove mineral stains and water stains in wood such as black marks caused by iron or steel on high tannin wood like oak. Oxalic acid is the primary component in most marine wood cleaner/brighteners.

The third stain is two part A/B bleach used to remove or reduce the natural color of wood. For example you can remove almost all the brown coloring in walnut or mahogany.
 

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Discussion Starter · #6 ·
Actually, oxalic acid dye is not the thing to use. Pigment stains like Minwax consist of a mixture or dye stains and pigment stain. A little resin (varnish) is added to adhere the pigments to the wood. When you use a chemical stripper, the stripper will dissolve the resin and allow the pigment to be removed. However, the chemical stripper will not affect the dye stain which has been absorbed into the cell structure of the wood.

The process to remove a stain like Minwax Wood Finish is to first apply a chemical stripper containing methylene chloride. This removes most of the pigment color but leaves the dye color. To remove--or at least greatly reduce the color--you need to use a chlorine bleach. The chlorine used in swimming pools will work fine. Apply it and keep the wood wet with more bleach until the color--at least most of it--is removed.

Oxalic acid bleach is used by woodworkers to remove mineral stains and water stains in wood such as black marks caused by iron or steel on high tannin wood like oak. Oxalic acid is the primary component in most marine wood cleaner/brighteners.

The third stain is two part A/B bleach used to remove or reduce the natural color of wood. For example you can remove almost all the brown coloring in walnut or mahogany.
Howie thanks for an understandable explanation to help put this into perspective for me. Because I used both additional stripping and the oxalic acid I was not really sure what had generated the color reduction. From your explanation it was the dye that was still left in the wood. But the important thing to me was that the color was now consistent and not blotchy. So in fact I applied additional wood dye and the color darkened as I wanted it to and it did not blotch.

So I got lucky on this recovery and the result now looks fine.

Thank you.

Gary
 

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The oxilac acid will do a little lightening and I felt like it was enough in this application. I think bleach would have been too much and would be harder to recover from. Sometimes when you use bleach on light colors it's difficult to make it look like wood again. It kinda gives it a plastic look.
 

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Discussion Starter · #8 ·
The oxilac acid will do a little lightening and I felt like it was enough in this application. I think bleach would have been too much and would be harder to recover from. Sometimes when you use bleach on light colors it's difficult to make it look like wood again. It kinda gives it a plastic look.

Steve no harm done and all is finally well with this project.

Gary
 

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>>>> So I got lucky on this recovery and the result now looks fine.

Lucky is always good.

The paint stripper removed most of the pigment stain. It's the pigment stain that causes most of the blotchy appearence. In fact a technique used by many experienced finishers when dealing with blotch prone wood is to use a dye stain rather than pigment stains. Dye stains tend to blotch less than pigment stains.
 

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Discussion Starter · #10 ·
>>>> So I got lucky on this recovery and the result now looks fine.

Lucky is always good.

The paint stripper removed most of the pigment stain. It's the pigment stain that causes most of the blotchy appearence. In fact a technique used by many experienced finishers when dealing with blotch prone wood is to use a dye stain rather than pigment stains. Dye stains tend to blotch less than pigment stains.
Howie this is a lesson learned for my future projects. Thanks.

Gary
 
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