On 15 May, 23:50, stuart noble wrote:
The Natural Philosopher wrote:
whisky-dave wrote:
I've taken most of the varnish off of some stair banisters and two
hand rails that had a dark varnish on them, most of the remaining wood
still isn't as light in colour as I'd like it. I was hoping to find
something in a
high street B&Q or somewhere. I've found a few suppliers of chemicals
*like oxalic acid and hydrogen peroxide and sodium hydroxide, but I'd
*like something a bit easier and perhaps safer, some can of something
that says "I lighten and bleach wood" on it.
I'm not sure what wood it is, but assuming it;'s not expensive wood.
Any suggestions......

None of the aboce are especially dangerous

Oxalic acid=Rhubarb (leaves?)
Hydrogen peroxide= hair bleach
Sodium hydroxide..well that is a tad excessive: it's caustic soda but
isn't a huge issue though it will belach (and rot) fabrics.

I think you left one out - sodium hypchorite IIRC is standard houshold
bleach.

However, really all this farting about with cheap wood seems pointless.

Paint them or get hardwood ones made or something. Life's too short.

The only bleach that might work is the 2 part caustic/peroxide type, and
that will lighten the wood itself but not any stains or varnish that may
be left from the stripping.

The peroxide in woodworking bleach is about 30 times stronger than hair
products and stings like crazy. Not something I'd recommend unless
you're going to take precautions- Hide quoted text -

- Show quoted text -

Dear All
Caustic products (ie sodium or potassium hydroxide) are used to
extract hemicelluloses from the surface of the wood and thus change
the structure of the outer parts. For that reason I do not use them
(execept in the lab to extract the hemicelluloses!).
If I were to lighten the wood I would consider the chlorine based ones
but agree with the post that lightening wood like this is a
questionable objective. If you want them light - paint them. They were
never designed to be seen as wood in the first place so to so so now x
years later is not really in keeping with the original building. Who
knows in 50 years time someone may say liken the action to the way in
which in the 1950s all the Victorian panelled doors were covered up
with hardboard!
Rant over..
BTW oxalic acid is pretty nasty stuff and if there are any children
around --- care
Chris