Preconditioner: A prerequisite?

Is preconditioner an absolute necessity for water-based stains? March 20, 2001

I am using water base finishes. Do I have to use a pre-conditioner before I apply the stain or can I use polyurethane? I'm worried about grain raising. I have also read something on using a dye that you mix in with polyurethane to make it the color you want.

Forum Responses
If you are considering dyeing polyurethane to get your color, why not instead use a tinted water based sealer? This way you take all of the compatibility issues out of the equation and get your color in one step.

You could also use a water based wiping stain or spray stain if you need a richer look.

Don't drive yourself crazy worrying about raising the grain. If you do raise the grain, once the surface has thoroughly dried, sand lightly with a 220 grit paper. If you're using a WB poly, you're going to A) raise the grain, and B) have to sand between coats anyway.

A trick pros use is to rub a damp towel over the surface prior to using a water base product. Once dry, sand with the 200 grit at a diagonal to the grain. This removes the raised grain "fuzz".

You don't have to use a pre-conditioner, but depending on the type of wood, a pre-conditioner, gel stain or seal coat of shellac can prevent blotching and provide a more even coat. You can also try NGR (non-grain raising) stains.

Adding stain or dye to the finish is called a toner. It's a method to get even color.

I recently started using Crystalac water based poly. I spray it on with a cheap HVLP gun. Sanding sealer or conditioner is not recommended. There are no brush marks and it flows well and dries fast.

From the original questioner:
I want to know the best combination of stain and topcoat for the water base scenario. I have been using the Minwax line of water base finish. The results have been passable.

If you have to seal the wood, try wood size from Franklin. You can spray or brush it. After it dries overnight, sand it to knock the grain down. Then try an oil base stain, then topcoat with Oxford hybird Vanish or any of their other water base products. The look is great and the stain will not blotch.

If you're in a hurry to complete this and have had good luck with Minwax, mix the Minwax water base stain with their waterbase poly finish, about 1 part stain to 5 parts finish. Apply it, let it dry overnight, and lightly sand with a 220 grit. To get the color you want, apply additional coats of the stain/finish mix. When the color is right, apply several coats of plain finish.

Get a copy of Andy Charron's book, "Water-Based Finishes." Also, Bob Flexner's book "Understanding Wood Finishing." This book will explain techniques to color wood evenly (among every other topic on the subject of finishing).

The key is using a good quality water base stain. Gel stains work better on blotching than liquid stains do.

With the proper sanding schedule and a low water-content WB, you should not experience any extensive grain rising. Prior to staining, sand with 320 grit, then apply your first thin coat of stain. Also, to help eliminate splotching you can apply a thin "spit coat" of blonde shellac to act as a conditioner. WB's have good adhesion to shellac.