Sanding, Planing, and Stain Matching

Sanded wood and planed wood take stain differently. For a good match, prep all the wood the same way. February 12, 2010

Question
I recently added on to an existing set of cabinets made of alder that were outside under a large patio. This is the first time I've used alder. The original stain used was a wipe-on walnut. The outer side of the cabinets seems to have lost all the red and has turned more of a golden brown. I had a paint and stain supplier do a match on a piece of the wood I purchased that had not been sanded yet, just planed down. When I stained the new cabinet they did not match up. We tried the stain on several other pieces of unsanded wood and it seemed to match very well. When we tried it on sanded pieces it was a different shade. Has anyone experienced this before?

Forum Responses
From Professor Gene Wengert, Sawing and Drying Forum technical advisor:
Planed wood has sharply cut fibers (microscopic level) while sanded wood has fractured, torn (fuzzy) and often bent-over fibers. The planed fibers do not absorb as much stain as the fractured fibers. Hence the difference in color.

This effect is even more pronounced with wood that has tensionwood regions. The stain will look blotchy. The weak tensionwood fibers tend to fracture, fuzz and bend over and also are high in cellulose (cotton is cellulose) content, so they absorb really well, while the rest of the region (non-tensionwood) does not absorb as well. Tensionwood is a growth event caused by having a tree growing under stress, such as a strong west wind much of the time, a heavy branch in the tree, a crooked tree.

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From Paul Snyder, forum technical advisor:
Smooth wood doesn't hold as much of the stain on the surface as rougher wood and will be lighter in color. Always do your color testing/samples on wood that's prepped the same as you would normally do for the final product, and do larger samples to get a more realistic idea of the results you can expect.

If you sand the wood to 180 or 220, it will stain lighter (using a wiping stain) than it does when you sand to 120 or 150. I usually sand to 150 before staining.

Also, you have to account for the stain fading with time and the wood changing color as it ages. In direct sunlight, the stain will fade and the wood will lighten (bleach) over time. As the finish starts to fail, the wood will turn grey.

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From Professor Gene Wengert, Sawing and Drying Forum technical advisor:
I do not believe that indoor cabinets will experience graying as the finish fails. Outdoors, it is possible.

I had an alder desk and shelves that lasted over 20 years with little change in color. They were in an office with a large south-facing window, so they got plenty of sunlight indeed.