Removing Metallic Stain from Mesquite--Wahhh!

[Tom Winship]

Hey guys, don't normally hang out here but I recently built bedside tables from mesquite. Finished with 5 coats of Minwax Tung Oil. They are about 6 months old.

During the night water was spilled on the top of one. Water was wiped up, however there was a metal lamp with a stamped metal bottom on the stand. Even though it was wiped off also, evidently the water reacted with the metal and made a nice black ring on the stand.

I have tried plain water, and water with Dawn dish soap to get it off.

Any silver bullet ideas?

Thanks.
Tom

[Phil Phelps]

I wish I had a magic solution, but I don't. However, I think you have made a good case for tung oil. Water marks left for a long time on oak floors never come out because they have penetrated too deep. You may try sanding to bare wood and beyond. Let's hope the ring sands out.

[Chris Padilla]

Oil has ZERO protection from water as you're finding out...actually, it is zero protection for just about anything. Also, you don't really have "5 coats" of oil on the stand either: oil does not build up as it is not a film finish.

However, oil looks great and easy to apply and easy to fix. One way to give oil some protection is to topcoat it with some clear shellac. Shellac would have likely kept that water out. Another idea is to apply wax on top of the oil. This is also pretty weak protection but it is better than oil and it might've withstood the water penetration...maybe. One step further...put wax on the shellac on top of the oil. :D

So, after all that rambling, Phil has the best idea: sand it out. Since this is an oil finish, you ought to be able to reapply it with little effort and with little notice that you had a ring in the first place. Once done, at least wax the stands if you don't want to go the shellac route....

[Mike Wilkins]

You could also try wood bleach. I refinished a walnut top hutch recently with a prominent black water ring. The wood bleach took out the stain, leaving only a slightly rough raised grain to sand down. Worth a try. Just make sure to follow the instructions on the container.

[Scott Holmes]

I'm going to go with the wood bleach method too. That's the best way to remove the black stains. Especially metal and oak the metal react withthe tannin acid in the oak and you get black stains.

FYI - Minwax Tung Oil Finish is linseed oil, urethane varnish and mineral spirits so it's not an oil finish it's an oil/varnish blend. More protective than just oil but still can't hold up to water very well.

Sanding will work but you will need to remove wood; then you will have a slight depression.

[Phil Phelps]

I'm going to go with the wood bleach method too. That's the best way to remove the black stains. Especially metal and oak the metal react withthe tannin acid in the oak and you get black stains.

FYI - Minwax Tung Oil Finish is linseed oil, urethane varnish and mineral spirits so it's not an oil finish it's an oil/varnish blnd. More protective than just oil but still can't hold up to water very well.

Sanding will work but you will need to remove wood; then you will have a slight depression.

I have been tempted, but never have bleached wood. Won't bleach change the color of the wood? If so, the top won't match the surrounding wood. If I were sanding the stain out, I'd belt sand the entire top. If you are bleaching, what strength?

[Scott Holmes]

Belt sanding the entire top will work too. The stains only show up were the water got in so a little wood bleach may follow the same entrances and work, it may not.

If it woks adding a little stain should blend it and if not....Then sanding the entire top is a good choice.

[Richard M. Wolfe]

The metal reacted with tannins in the mesquite to cause the stain. Using wood bleach might remove the stain but the main effect of wood bleach is to - bleach the wood :rolleyes:, which I doubt you would want to do. Oxalic acid is recommended to get rid of metallic stains. I can only tell you what I've read, as I've not used it. (I have used wood bleach, which definitely removes color from the wood).

[Scott Holmes]

Oxalic acid is recommended to get rid of metallic stains. Oxalic acid IS Wood Bleach