# Is there a way to stop cherry from darkening?



## gideon (May 26, 2010)

Is there?

What I've finished in tung oil/varnish mix tends darken but with wipe on poly urethane, it seems to stay a bit lighter - I think.

Any ideas?


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## mmwood_1 (Oct 24, 2007)

If you use a water based acrylic finish, it will not darken. At least, that has been my experience.


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## Dave Paine (May 30, 2012)

A water based finish may not cause it to darken at the time of application, but it will darken over time with exposure to UV no matter what the finish. Even UV inhibitor does not prevent, just slow down the process.

I suppose paint will prevent it from darkening, but then it would not look like cherry. :icon_smile:


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## Shop Dad (May 3, 2011)

My understanding is that it will darken in a couple years regardless. Like Purple Heart looses that nice color and other woods change over time.


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## Steve Neul (Sep 2, 2011)

The best you can hope for is to slow the darkening process. Kwick Kleen makes a product called Sun Block that is like a sun screen made for wood. Then topcoat with a marine grade spar varnish such as Epifanes woodfinish.


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## mmwood_1 (Oct 24, 2007)

I can say this much, that I used a water based clear acrylic finish on a cherry table I built for a customer, and 5 years later, it had still not darkened hardly at all, just a shade or two darker than raw wood. I swore off water based finishes for that reason.


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## HowardAcheson (Nov 25, 2011)

No, unless you paint it with an opaque paint.

There are two things that cause cherry to darken. One is the UV in sunlight and other sources. The second is oxygen which causes oxidation. Keeping cherry completely in the dark with stop UV darkening but oxidation will still occur


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## Brian T. (Dec 19, 2012)

Sunlight is a full spectrum of colors, we all know that. Chlorophylls in green leaves soak up red and blue light for photosynthesis. The one color of light that isn't used very well at all is green (540nm). That's mostly reflected so that's what we see.
In cherry wood, there are all sorts of complicated molecules that give the wood it's color. Those things soak up all sorts of wavelengths/colors and reflect what we see. If you change the chemistry of those molecules, you change what light they absorb and reflect.
UV light has the most energy and it whacks molecules but good (spell "sun burn").
As H.A. has just added, maybe the bigger issue is bleaching/damage from exposure to oxygen in the air.
Wood finishes are pretty thin, the oxygen will diffuse through that, sooner or later.


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