Those Black Stains On Your Stripped Stock

[painter777]

Most everyone whose stripped a Mil Surp stock has seen them.... The Black stains that never seem to go away no matter what you try. I've seen/had my share.
If your interested look over this older link I pulled from the CMP Forum.
Also look over this link to Bar Keepers Friend, it contains Oxalic Acid which is found in the wood bleaches.

Black stains on M1 Carbine stocks - CMP Forums

Removing Stains from Teak and Walnut Furniture

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After Multiple Treatments:

Information

Warning: This is a relatively older thread This discussion is older than 360 days. Some information contained in it may no longer be current.

[tenOC]

I just used Oxalic Acid on the heel of an RMC stock I got with black stains from a rusted recoil plate. It worked pretty well but used a q tip to dab it only on the stained part of the wood. If I got it on the unstained wood next to the stain it was lightening that area. Maybe it wasn't bleaching the wood as I assumed and was changing the oil color instead, but I stopped allowing it to bleed onto the unstained portions of wood. In my approach you can still see the stain in underlying fibers but the surface was proper color enough to blend in with the rest of the stock.
Supposedly it won't change the color of wood but reacts with the rust. In my case it was lightening the color of whatever was on the wood. If you're stripping it completely it probably won't matter.

[painter777]

Oxalic Acid

Hi Ten,
Drying up down there or still raining?
My brother has a outside stairway down to his basement that had a running waterfall on it. About 3' of water down there at the worst of it. He's needing my help but I need to stay near home, having some issues with my Mother.

Your RMC Stock,
Good that you were careful. Oxalic Acid can come in many different .... I'll call strengths. I have a 2 part mix we used at work for bleaching out stains on new unfinished wood.
Like those raw stair treads covered in muddy boot prints or single tread that is naturally 3 times darker than the others and about to be finished Natural. Fireplace Mantel tops with coffee rings... etc. This stuff will eat the flesh to the bone...... like Hydrogen Peroxide on steroids.
Usually treat the stain, once gone a quick light wash with it over the entire piece of wood, sometimes having to neutralize it. Best for full strip and refinish jobs.

When possible light precise dobbing and brushing of the Bar Keepers can give great results.
But it can take 6 or more applications on bad blackened spots. Then finish up by quickly wiping the entire surface with it and damp rag it off so it blends. This way the treated area won't stand out.

If I got it on the unstained wood next to the stain it was lightening that area. Maybe it wasn't bleaching the wood as I assumed and was changing the oil color instead

It was bleaching both the wood and the oil. We'd mask off any area we didn't want it to 'Bleach'.
I've seen others instead of masking off, they'd use water and soak the area they didn't want the 'Bleach' to contact. I prefer masking and being neat, unless doing the complete piece.

I'd buy the 2 gallon kit. But advise only using when all others failed. Here's a pic of the kit and a link to some before and after pics. Used 1 part to 1 part it will strip all the old finish to include any rack paint. A last resort thing.



http://www.milsurps.com/showthread.php?t=25255

[tenOC]

Hi Ten,
Drying up down there or still raining?
My brother has a outside stairway down to his basement that had a running waterfall on it. About 3' of water down there at the worst of it. He's needing my help but I need to stay near home, having some issues with my Mother.

Your RMC Stock,
Good that you were careful. Oxalic Acid can come in many different .... I'll call strengths. I have a 2 part mix we used at work for bleaching out stains on new unfinished wood.
Like those raw stair treads covered in muddy boot prints or single tread that is naturally 3 times darker than the others and about to be finished Natural. Fireplace Mantel tops with coffee rings... etc. This stuff will eat the flesh to the bone...... like Hydrogen Peroxide on steroids.
Usually treat the stain, once gone a quick light wash with it over the entire piece of wood, sometimes having to neutralize it. Best for full strip and refinish jobs.

Yesterday it was sunny and 65 or so degrees after days of more steady, or even hard rain. Today it started raining near lunch and has been on and off since. smh. The basement used to flood during these events but I finally discovered what was causing it and cured it. People think the Northeast gets more rain but we get 11 or 14 more inches than Seattle. They have more rainy days, but we get buckets.

This RMC I used the Barkeepers Friend premixed in the soft cleanser version. It's the only experience I've used so far. There were 3 versions of the name brand at Home Cheapo, and all were really affordable. Instead of mixing I went the easy route and while it did take a few days of applications (while watching TV) it did work. After a while I tried slathering it on and didn't like the results on surrounding wood, so went back to deliberate application. I put a little oil on it and the black was seen underneath but I'm happy with the turn out without having to strip the stock.

[imarangemaster]

Before and after using 2 applications of the complete stock with Bar Keeper's Friend (in a paste form) on my Q-RMC stock. Allowed to soak for an hour each time, then rinsed and brushed each coat. Going to use Minwax "Dark Walnut" penetrating wiping stain, then use Raw linseed oil and Boiled linseed oil in a 4/1 mix to finish. It makes a big difference on drying it. The residual dark spots should all but be invisible

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