Bleaching Wood

[starrystar]

Hello everyone.

I need some advice.

I have a walnut table which, over the past 20 years, has bleached in the sun - that is, apart from the middle of it which has always had something sitting on it.

I've stripped and sanded the table back but the dark mark is still there.

I've been thinking of trying a bleach on it but don't know what to do. I've researched and a mix of caustic soda and hydrogen peroxide seems the only option (although I've not idea how to mix it). Does anyone have any tips or experience?

Thanks in advance

 

[TheTiddles]

Do you like the light colour? It’s usually easier to make wood darker than lighter so the easier option is to slowly stain the light to match the dark spot
Aidan

 

[Richard_C]

Presumably the underside has stayed dark. That's your laboratory where you can try things out. Hydrogen peroxide is a gentle bleach ( "peroxide blonde") so you could try that on its own as a first step. If it does show promise, your difficulty will be blending round the edge of the dark bit. As suggested above, an all over darker stain built up carefully might be the way to go. It strikes me that mixing strong caustic with hydrogen peroxide might give you a violent reaction, check it out carefully.

 

[Myfordman]

oxalic acid is what I've used before to bleach wood

 

[Sheffield Tony]

I have used the 2 pack sodium hydroxide / hydrogen peroxide bleach. It was very effective at achieving a bleached driftwood look quite quickly. Quite aggressive. I can't imagine I would have the skill to make it blend in with the sunbleached parts. More likely I'd end up with a whiteish patch instead of a dark one !

As mentioned already, might be easier to darken the rest - sneak up on the colour by repeated application of a dilute Van Dyke crystal solution ?

 

[mrpercysnodgrass]

I think you have two options with this, you could sand it back much more aggressively, starting with 100g and working down to 240g that way you will remove the faded surface and you will be left with the darker natural colour. If you want to keep the faded colour then you only option is to use A+B bleach but use it over the entire surface not just the darker patch. If you do go down the A+B route neutralise with white vinegar, rice with plenty of clean water at least three times then leave for four days before applying any sort of finish.
Is the top a solid piece or veneer? If it is veneer you will have to be very careful you do not sand through, I would sand by hand and not use a machine.

 

[Cabinetman]

I really can’t comment on bleach, sorry, but it certainly looks, from the way the pattern repeats that it is veneered.

 

[sunnybob]

That size and thickness also leads me to believe its veneered. I suggest a coat of finish to your choice and stand the same ornament back in the same place.

 

[TheTiddles]

That size and thickness also leads me to believe its veneered. I suggest a coat of finish to your choice and stand the same ornament back in the same place.

The furniture making equivalent of turning up the radio to hide the annoying rattle in the car!

Aidan

 

[starrystar]

Thank you so much for all the replies.
I'm worried about sanding too much in case I end up with a wafer thin mint of a table!
I've got walnut stain so it might make more sense to do that than bleach it, and I do want to try and get it back to how it was when I bought it.

I'll test on the underside which seems to be the same wood, so I can't tell if it's laminated or not.

 

[sunnybob]

The furniture making equivalent of turning up the radio to hide the annoying rattle in the car!

Aidan

If the annoying rattle costs half the value of the car to fix..... oh yes.

 

[starrystar]

I thought I'd do an update on the table now it's finished.

I didn't go with the bleaching in the end. I was too nervous of making a mess of it.
Instead I sanded down then Danish oiled and waxed it.
Pleased with the results.

 

[johnbaz]

Hi

The table came out fabulously

I've been collecting airguns for years and used to do a lot of stock refinishing, When there was blotchy wood I would mix strong bleach and water and slap it on with a cloth, If it was oil that had soaked in I used Oxalic acid crystals dissolved in warm water, I soaked a cloth in it and then put it over the stain for a few hours, It usually brought the oil out..

This is such a stock (Beech), It was the last one I refinished earlier this year, My hands are arthritic now so I probably won't do any more!

I used Alkanet root oil to give the warm colour then lacquered it from a rattle can!!, I used to use boiled Linseed oil for walnut stocks..

It's the middle one of these, This pic was taken before I refinished it, The stock was filthy, I started rubbing it down at the cheekpiece years ago but it was very difficult to remove the wood, I think the abrasive paper I used was rubbish!

John