Controlling Blotch in Birch Cabinet Doors

More thoughts on how to achieve even staining with troublesome woods like birch. June 28, 2006

Question
I just delivered cabinets for a den that I built out of birch. I applied oil stain and precat lacquer. The customer was very happy, but I thought it blotched more than I would have liked. I am a one man pro shop, so efficiency of process is key. What do you guys do? I probably could have done a seal coat of 1lb shellac, but felt this might make the color too light. This is really more for me to note for the next time. Thanks for your help.

Forum Responses
(Finishing Forum)
From contributor A:
On Birch, Maple, or Cherry we spray on a dye coat to get a uniform base color, then a wash coat then wipe with stain. This keeps the color uniform and can even mask sapwood if need be.



From contributor B:
I just finished a birch job with exceptional results on the finish (zero blotching) after doing some homework here and reading Jeff Jewitt's book. Here is what I did to produce a very rich, deep finish:
- RO sand 220
- spray on dye stain (50/50 lacquer thinner and alcohol plus desired dye concentrate) Be very careful to get it on evenly!
- sanding sealer
- fine sanding sponge

- wipe on stain of desired color
- top coat x 2


From contributor C:
Washcoat before wiping stain is a fine method of stain control but means considerable extra time for a large set of cabinets. Consider the type of stain you're using. Certain stains are less prone to blotch than others. I find that a fast dry solvent stain with low oil content like SW Sherwood line is exceptionally good at controlling blotch, even on unsealed birch, when applied by spray and controlling the amount being applied. In other words, just don't flood it. Good surface preparation is assumed also. Spraying an NGR (dye) stain prior to the wiping stain is another way of reducing blotch especially when strong colors are ordered and does not necessarily need to be sealed between the dye and the stain. Quality first but it pays to experiment.


From contributor D:
Itís quite common to use wash coats to control blotching if thatís the way you go. Because the wash coats seal off the wood, it makes sense that the color will be lighter. To overcome this, make up a start to finish sample, and check the color. If itís lighter than you want, you can darken the color until you hit your target. Think twice, and finish once.