Brazilian Mahogany damage

[rayaans]

Hi, I've been slowly renovating our Victorian property and getting towards the finishing details. One of them is the banister which has got me stumped!

I'm trying to tackle it on my own. So far the shellac has been stripped, along with whatever stain was under it leaving bare wood.

Turns out it's Brazilian Mahogany and a precious leak in the property has really whitened the small curved pieces and they look like they've just been stained over in the past.

I have no idea how to get it back to the original red colour.., or even if that will be possible.

Any ideas greatly appreciated

 

[Cubist]

I envy you; real mahogany is so rare to see these days and it's equally pleasing to hear from someone determined to preserve such an example in their home. Thank you too for the photos as these have cleared up one possibility insofar that curved pieces of timber such as those are often produced through steam bending which can draw some of the natural colour from the wood. However, and fortunately, the grain structure of the example shown suggests that it was carved from a solid piece of timber and therefore my first thought can be disregarded. Which leaves me with the following offering regarding root cause.

Hands love curves. Mine certainly do, and on one notable occasion in the Villa Borghese I got my knuckles firmly rapped by an attendant for fondling the foot of a bronze statue of a nymph. But I digress. Hands love curves, particularly when found on bannister rails. You may have noticed when using those stairs that you seldom actually grip the straight sections of the rail as you climb or descend, rather you use a light and perhaps gentle contact as you use the bannister as a guide. That changes though as you meet a turn or curve and your grip often becomes tighter as you use it to slightly pivot your weight onto a new heading. That increased pressure has two detrimental effects however insofar that the hard coating over the curve experiences greater abrasion and therefore can eventually wear through to the bare wood - very quickly with some softer finish materials such as shellac/French polish. As the coating wears away, body oils are transferred from our hands to the wood and these can be absorbed to induce dark/blackened stains. We have an example here of an oak timber that has acquired a polished and oily patina from perhaps centuries of people like me using it as a corner is turned.

From a remedial treatment perspective you may never get the colour of those curves to match that of the main bannister rail. Decades, perhaps centuries, of innocent fondling will have pushed those body oils far into the wood. As a consequence the oils will resist the use of almost any colouring agent and make successful colour matching almost impossible. A good professional furniture restorer would be much more successful than any amateur but I suspect no-one would give you a guarantee of success and the cost of the attempt may be more than you might expect. That aside, you could try using methylated spirits to repeatedly - over several days - wipe down the surface of the wood to lift the oils before trying any suitable stain or dye to restore the base colour (Note; you may need to blend several stains or dyes to achieve a close match). By the way, theres a slightly more dangerous technique using meths that should only be attempted in a workshop away from the house. This involves painting the surface of the wood with a thin film of meths and setting it alight to draw and burn off the oils from the wood - have a large wet cloth or fire extinguisher to hand if you want to try this.

 

[paulc]

you could try using methylated spirits to repeatedly - over several days - wipe down the surface of the wood to lift the oils before trying any suitable stain or dye to restore the base colour

If you use regular "over the counter" meths, you may find the wood taking on a purple tinge. Industrial denatured alcohol (IDA) would be preferable if you can get hold of the stuff (and have a licence).
That said, it is no longer mandatory for completely denatured alcohol (CDA or meths) to contain methyl violet, so shop around. Bioethanol could well be a better alternative and easier to obtain than IDA.

 

[rayaans]

I envy you; real mahogany is so rare to see these days and it's equally pleasing to hear from someone determined to preserve such an example in their home. Thank you too for the photos as these have cleared up one possibility insofar that curved pieces of timber such as those are often produced through steam bending which can draw some of the natural colour from the wood. However, and fortunately, the grain structure of the example shown suggests that it was carved from a solid piece of timber and therefore my first thought can be disregarded. Which leaves me with the following offering regarding root cause.

Hands love curves. Mine certainly do, and on one notable occasion in the Villa Borghese I got my knuckles firmly rapped by an attendant for fondling the foot of a bronze statue of a nymph. But I digress. Hands love curves, particularly when found on bannister rails. You may have noticed when using those stairs that you seldom actually grip the straight sections of the rail as you climb or descend, rather you use a light and perhaps gentle contact as you use the bannister as a guide. That changes though as you meet a turn or curve and your grip often becomes tighter as you use it to slightly pivot your weight onto a new heading. That increased pressure has two detrimental effects however insofar that the hard coating over the curve experiences greater abrasion and therefore can eventually wear through to the bare wood - very quickly with some softer finish materials such as shellac/French polish. As the coating wears away, body oils are transferred from our hands to the wood and these can be absorbed to induce dark/blackened stains. We have an example here of an oak timber that has acquired a polished and oily patina from perhaps centuries of people like me using it as a corner is turned.

From a remedial treatment perspective you may never get the colour of those curves to match that of the main bannister rail. Decades, perhaps centuries, of innocent fondling will have pushed those body oils far into the wood. As a consequence the oils will resist the use of almost any colouring agent and make successful colour matching almost impossible. A good professional furniture restorer would be much more successful than any amateur but I suspect no-one would give you a guarantee of success and the cost of the attempt may be more than you might expect. That aside, you could try using methylated spirits to repeatedly - over several days - wipe down the surface of the wood to lift the oils before trying any suitable stain or dye to restore the base colour (Note; you may need to blend several stains or dyes to achieve a close match). By the way, theres a slightly more dangerous technique using meths that should only be attempted in a workshop away from the house. This involves painting the surface of the wood with a thin film of meths and setting it alight to draw and burn off the oils from the wood - have a large wet cloth or fire extinguisher to hand if you want to try this.

Thank you, that's a very comprehensive answer.

Unfortunately that particular piece has gone completely white after I hit it with another coat of Liberon stripper followed by their wax and polish remover. I think all the remaining stain has gone.

I've tried meths on it a few times but it almost doesn't seem to do anything (on the other pieces the wood becomes a rich red-brown colour).

I think I may try some wood colour reviver in the hope it'll make a difference but if not, staining may be the way to go - planning on using a spirit based stain.