On 6/27/2017 5:14 PM, John Wiedmann wrote:
replying to thermo102, John Wiedmann wrote:
I'm entering this conversation about seven after it was posted. Hopefully
someone is out there who can advise. We have a "real" knotty pine paneled
den, built by me I n 1985. It was finished with urethane. It has not been
subjected to cigarette smoke, and the kitchen, although adjacent via a
doorway, has an exhaust fan that gets rid of cooking fumes pretty well.
The
paneling has yellowed over the last 32 years. Some individual panels are
remarkably darker than panels immediately adjacent on either side. It
is not
clear why this is the case - but it is. I've read about five or six
different
cleaning products to use, so it appears a few trial tests in inconspicuous
areas will determine which is most effective. My goal is to lighten the
wood
and then refinish it again with either a urethane or polyurethane.
Question:
how does one effectively deal with the grooves? Could (should?) they be
cleaned (with whatever product is chosen) with a softish nylon bristle
brush? Also, has anyone used such a scrub brush to apply the elbow
grease for this
type of project (flat surfaces as well as grooves)?



The only way to lighten and brighten the wood is to remove the finish
and the top layer of the wood that has oxidized over the years. It may
go through to the point lightening will be minimal.

You can try wood bleach but to do an entire room bould not be too easy.
I'd paint it before doing that method.
http://www.woodmagazine.com/material...th-wood-bleach