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Byron Trantham
07-11-2007, 2:43 PM
I need to finish a birch bookcase. Which is least likely to blotch - oil based stain or water based dye?

Steve Schoene
07-12-2007, 4:37 PM
Water based dye is less likely to blotch than oil based stain. That doesn't mean there will be none but that it will be less, and less objectionable.

Kim Spence
07-14-2007, 1:10 AM
A few options...

1. Treat the wood with a mixture of 10% boiled linseed oil and 90% mineral spirits. Let the wood soak up this mixture. Apply again to spots that dry out faster than the rest of the wood, these are the spots that would have bloched. Now wipe off all excess and proceed immediately to staining with an oil based stain. Basically what this method does is saturates the spots that are "hungry" for liquid before applying color.

2. Apply (brush or wipe) washcoat of 1/2 or 1 lb dewaxed shellac. Let dry, scuff sand with 320 grit, and apply oil based stain. This prevents the stain from penetrating and blotching.

3. If you have spray equipment, spray vinyl sealer. Let dry and defwhisker. Mix a lacquer toner with the color you want and spray on the number of coats to get desired color intensity. In this case the color is all on top of the wood so if wood gets dinged in use the light birch will show through.

4. Water based dye applied by brush or rag will blotch badly. Spraying water based or a non grain raising (NGR) solvent based dye is a better option if you have spray equip.

5. Combination of methods - first spray a water based or NGR dye. Then seal with shellac or your choice of topcoat. Next glaze with an oil based stain or gel stain, then topcoat again. This will get you some really nice depth.

As you see lots of ways to do this all with some tradeoffs. Whatever you do, don't apply water dye or oil stains directly to bare wood or it WILL blotch badly.

Pat Germain
07-18-2007, 2:02 PM
I'm in the process of finishing a bookcase I just made from birch plywood. So far, I've applied three coats of General Finishes "Seal-A-Cell" Clear which is oil-based. It looks amazing! Seriously, I couldn't believe how good that sealer made the birch look. It gave the wood a nice, even, amber tone. There is no blotching whatsoever which I can see. Although I used clear, I'm pretty sure Seal A Cell is also available with stain included.

I can't wait to apply the final finish on top of the Seal A Cell. It's just a very basic bookcase, but it's looking much better than I expected. :)

Byron Trantham
07-18-2007, 2:47 PM
I'm in the process of finishing a bookcase I just made from birch plywood. So far, I've applied three coats of General Finishes "Seal-A-Cell" Clear which is oil-based. It looks amazing! Seriously, I couldn't believe how good that sealer made the birch look. It gave the wood a nice, even, amber tone. There is no blotching whatsoever which I can see. Although I used clear, I'm pretty sure Seal A Cell is also available with stain included.

I can't wait to apply the final finish on top of the Seal A Cell. It's just a very basic bookcase, but it's looking much better than I expected. :)

That's great to hear. I think I am going to use a Garnet shellac. I'll let everyone know how it turns out.