Walnut

semenza

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Hi,

  I have just landed a job to match an existing built in unit. Customer had the existing unit built about five years ago. It is on one side of a fireplace and they now want one on the other side.   It is solid black walnut.  I don't think it has been stained, just finish.

             Is it correct that walnut gets lighter with age?

             Does the color change taper off or stop at some point?

             Should I try for a match now, and hope it stays that way?

             Should I just finish the new one counting on it lightening and "catching up" with the old one in color?

Seth

srs
 
Hi Seth,

I use a lot of black walnut and from my experience, yes it will get lighter and yellower as it is exposed to UV.  If it was finished with any kind of oil concoction it will change very quickly.  If it was finished with water based material with UV inhibitors it will change much less quickly.  The color change will taper off, but never stop completely.  The other issue is the original color and character of the wood is very different depending on where the tree grew.  In southern Oregon, the black walnut was not native so it all came in with the settlers as seeds or seedlings.  If it grew low in the valley around a home with plenty of water it was browner and with less figure.  If it grew high up where the weather conditions were harsher it originally had a lot more figure and black/green/gray color - and a lot more internal shake break.

That said, I think you have to work with three different issues in trying to match something that already exists.  The first is the overall look, figure and color pallet of the original and whatever wood source you can find for the new part.  The second is the aging color shift.  The third is how the original was finished and how you plan to finish the new part.  From my experience I would not suggest trying to match the new to the old by staining or dying as those materials may well age (color shift) differently from the wood itself.  Instead, I would engage the owner by telling them the issues and showing them two samples of the wood you have, one finished with some sort of oil stuff and the other with Target Coatings new water based hybravar material that uses a hydrolised linseed oil base.  That material will pop the grain better than the traditional water based conversion varnishes and will tend to amber the walnut to likely more the color of the aged existing walnut. 

If the new work will get the same or more UV exposure than the existing, I think the color change on the new may tend to catch up with the old over time, but all bets are off as to whether it will ever really "match".  The bottom line is I think you are best to offer the client the option of "coming as close as you can based on the samples you show them" or replacing both sides if they insist on a real "match".  Hope this helps, and good luck with your project.  Just one more thing you likely already know about black walnut.  The dust can be very toxic for some people so be careful not only to protect your self while you work, but also to protect your client's family from any on site cutting, routing or sanding you do.

Jerry

semenza said:
Hi,

  I have just landed a job to match an existing built in unit. Customer had the existing unit built about five years ago. It is on one side of a fireplace and they now want one on the other side.   It is solid black walnut.  I don't think it has been stained, just finish.

             Is it correct that walnut gets lighter with age?

             Does the color change taper off or stop at some point?

             Should I try for a match now, and hope it stays that way?

             Should I just finish the new one counting on it lightening and "catching up" with the old one in color?

Seth
 
Hi,

      Thanks for the replies.  I can get some idea of the original wood color  on the existing piece from the back edge of shelves which were not finished and have been out of the light.  I can get new stock that is very close to that.  The grain pattern as well.  I do not think that I will be able to find out how the existing piece was finished.  I am almost certain that it was not stained. As to the type of finish ???    It has indeed lightened and yellowed in just five years.  The new piece will get the same UV exposure as the old.  I do not think that there is a practical and controlable method to pre-lighten the wood.

Seth
 
Hi,

    I took some samples to the customers house  to show them and talk to them about the woods color change etc. The samples were darker and browner. I took a shelf out of the existing unit  and there was a nice borwn stripe  where it had been shielding the sides and back from the light. The sample were a near perfect match to the stripe. It did not take much convincing of the situation when they checked that out.  I am good to go now and they are in tune also. :)

Seth
 
I read a story about a guy that had to match old work with new. He set bowls of Amonia around the room and closed all the doors and windows for an extended time. It colored all the wood a golden color I believe. I don't know if this is an urban legend or if it works.
 
Bill Wyko said:
I read a story about a guy that had to match old work with new. He set bowls of Amonia around the room and closed all the doors and windows for an extended time. It colored all the wood a golden color I believe. I don't know if this is an urban legend or if it works.

It does work, it's called 'fuming'.

Did it myself on this piece for college:
[attachthumb=#]

The centre section is fumed oak.

Basically, it's used to darken/age timbers, traditionally oak in particular. It comes from the use of oak beams in large, ancient farm buildings in Europe, where cattle or horses would be kept inside. Over the centuries, the oak would turn black with exposure to the ammonia in the animal's urine. Fuming just speeds up the process.

For small pieces of timber, it's really easy to do in/just outside the workshop. All you need is a couple of teaspoons of ammonia & a plastic dustbin. The piece in the picture took around 3 hours, IIRC.
 
I always assumed it was just age that turned oak black, the roof timbers in the house I grew up in in England were totally black and hard as concrete.
(and we didn't pee in the attic much), of course they were nearly a thousand years old.
 
in a house 1000 years old the colouring also comes from the soot of the cooking fires

houses up until 600 years ago where built without chimneys, there was only a smoke hole in the roof

yes the oak will have been as hard as iron

oak case hardens with age, its one of the reasons why there are so many medieval half timbered buildings are still standing

 
Steve Jones said:
we didn't pee in the attic much

No, but in the olden days the inhabitants would have done, in chamberpots. No en-suites back then, you see!

But DD is right, in domestic rather than farm buildings, much of the colouring comes from soot...
 
not quite jrb

i said "some" of the colouring is from soot

even 6-700 years ago animals and humans lived in the same building during the winter, on end for humans the other for cattle

we are talking about ordinary people, not lords and ladies

and not serfs

serfs would have been very lucky to have had a pig and a few chickens and the house probably wouldnt have had any wood to speak of

probably wattle (twigs) and daub (cow dung) walls and a thatch roof

doors, forget it a cloth maybe
 
Hi,

  Well now, that amonia trick is pretty neat.  But I think I will avoid telling my client to go pee in the corner! :D

Seth
 
Bill Wyko said:
I read a story about a guy that had to match old work with new. He set bowls of Amonia around the room and closed all the doors and windows for an extended time. It colored all the wood a golden color I believe. I don't know if this is an urban legend or if it works.

This sounds like a (true) story from this book.
 
This sounds like a (true) story from this book.

Good book with entertaining stories from a great finisher.  George Frank was a master and an inspiration to the finisher's art.
 
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