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hughie
7th October 2009, 01:54 PM
I have often wondered what causes the colour to fade on timber. There are perhaps some obvious effects such as ultra violet and Oxygen.

And then what can we do to delay or prevent this occurring. :?

Rum Pig
7th October 2009, 02:47 PM
If I remember correctly Richard R said their is nothing you can do to stop it changing colour it is just a mater of time.

We can delay this change by applying a coating that will buffer the timber from the elements like wax. The better the buffering capability's of the finish the longer lasting the effects.

This is my basic understanding of how things work I would need to do some research for more specific info.

Rum Pig
7th October 2009, 02:55 PM
Just found this had a quick skim but looks like some good info

118281

Rum Pig
7th October 2009, 03:14 PM
Found this not to much there but some
Fox Wedged • Timber • Timber Technical Data (http://www.foxwedge.co.za/fox_products/timber/timber_tech.html)

Ed Reiss
8th October 2009, 12:18 PM
And then what can we do to delay or prevent this occurring. :?

take a picture :;:D

Hughie, of course you realize that some woods like Cherry get darker with age.

Woodwould
8th October 2009, 01:32 PM
... some woods like Cherry get darker with age.

I've heard Americans talking about giving US Cherry (Prunus serotina (http://en.wikipedia.org/wiki/Prunus_serotina)) a suntan to age it, but European Cherry (Prunus avium (http://en.wikipedia.org/wiki/Prunus_avium)) fades in UV light (take a look at any antique French country furniture and it's a pale honey to clotted cream colour).

jefferson
8th October 2009, 09:54 PM
I'd defer to WoodWould on this one. He knows more than most.

The standard "secret" is to keep wood out of direct sunlight (and heat) and that will slow the process (light or dark).

Don't be too precious about it all though. By the time the timber has aged, so will have the turner. And it won't make too much difference then. :rolleyes:

I do quite a bit of work with river redgum (Euc. Cameldulensis if I have it right), re-cycled and "virgin". The new stuff still looks "new" after maybe 8 years. The re-cycled stuff has got darker, no question. No idea why.

Wiser head will prevail, no doubt.

hughie
9th October 2009, 04:19 AM
There are a number of products that boast protection against UV light. But another destroyer of colour etc is moisture. So we need to keep the timber out of strong light buy a good anti-uv sealer or varnish, moist seem to combine the water proofing and UV protection and have the added value of being a flexible coating


http://www.oceania.net.au/product_range/pics/ultra_v/Ultrav_timber_guard%20brochure.pdf

Feast Watson - Exterior Clear Finishes - Weatherproof (http://www.feastwatson.com.au/FinishesWeatherproof.asp)

Weathergard (http://www.wattyl.com.au/DIY/Pages/Weathergard.aspx)


DECKING OIL (http://www.bondall.com/_webapp_5410/DECKING_OIL)

MONOCEL CLEAR TIMBER VARNISH (http://www.bondall.com/_webapp_5403/MONOCEL_CLEAR_TIMBER_VARNISH)

BIO Natural Timber Oil - UV exterior timber oil (http://www.coloursbynature.com.au/about-bio-products/bio-natural-timber-oil)

Ed Reiss
9th October 2009, 12:08 PM
European Cherry (Prunus avium (http://en.wikipedia.org/wiki/Prunus_avium)) fades in UV light

hmmmm, didn't know that one Robert...learn't something today, :2tsup:

now the next time I have a couple, three rum and cokes, it'll probably kill those particular brain cells and I'll have forgotten that. :doh:

Woodturnerjosh
9th October 2009, 06:18 PM
Funny this should come up as I was only recently reading about a product designed to reduce the darkening of light and pale timbers. The product is by Ciba and called Lignostab 1198, on the website they refer to the darkening process as lignin photo-oxidation. There was a very informative pdf on their site but it seemed to be focussed on flooring and outdoor furniture, decks, etc.
Cheers
Josh

TTIT
9th October 2009, 09:57 PM
Just a thought to add here. One thing I've noticed since I've been playing with timber is that all species eventually fade to grey when exposed to the elements - - - - - except one :oo: - - - Australian Ebony (http://www.ttit.id.au/treepages/austebony.htm). It just gets blacker and blacker. So the answer to Hughies dilemma is simple - just start farming diospyros humilis, wait 40 or 50 years or so and you won't have to worry about fading timber ever again - providing everything you make is quite small :B:U

rsser
9th October 2009, 10:17 PM
Tassie Myrtle doesn't change much over time.

I have heard that oxidation is one cause of darkening as already noted. Also that finishes with UV protection have it to preserve the finish.

hughie
10th October 2009, 12:51 AM
Ern Glad to see your back from your walkabout. :U

What started me thinking along these line was a a couple of burls I turned up and one went dark and lost most of its lustrous colour. :~ The other has held up well [It was Myrtle]

I figured there must be something out there to by now that could delay or even prevent this sort of thing. The Lignostab 1198 looks like a goer. But I went to the website and tried to get a free sample of, gggrrh some glitch with the password setup/registration could not get it done, maybe try later.

rsser
10th October 2009, 07:33 AM
G'day Hughie,

Not back yet; just logging in with laptop and mobile phone as modem. (Trip report here (http://www.woodworkforums.com/f119/pilgrims-progress-104386/) if you're interested.)

Was thinking overnight about other timbers that I've found don't darken. Qld Maple (one sample only); Jarrah; Camphor Laurel (not much).

ElizaLeahy
10th October 2009, 01:33 PM
And then what can we do to delay or prevent this occurring. :?

Paint it...

hughie
10th October 2009, 01:53 PM
Paint it...


:U yeah right