Graining for furniture finishing.

"Graining" is a finishing technique to mimic and make the wood grain looked. The wood grain and pores looked can be made by the application stain or glaze with the special technique. Graining can be done manually by application stain with brush or cloth. In the big volume production, the graining can be done with the automatic machine that is called rotogravure machine (printing machine). Graining is done on a mass industry, carried out by printing technique using an automatic machine. The automatic machine is the basic machine for the production of decorative paper, wall paneling, decorative hardboard, m.d.f. or particle board panels. Natural grain and pores is wood part that gives high value of the wood product, but sometime bring the variation in the appearances. Wood is natural product which could have varied properties. Graining in the finishing process could be the alternative to make the wood looked appearance in the finishing to the flat surface that has no grain or pores as wood.

The graining in the furniture finishing usually is done with the glaze or wiping stain with brushing application. The glaze can be brushed with special technique to mimic the grains, pores or wood looked. We can make the wood looked finished to the non wood substrates such as: m.d.f., particle board, resin, polyurethane to make the wood looked finish.  It also can be the solution to make the wood finishing to the mixed wood which has big variation in the wood base color, grain pattern or pores. We can apply a toner or base coat to block the variation o the wood base color, grain and pores pattern to make the even and uniform base color, and then wood looked is made by the glaze application. 

graining with base coat as the base color

graining with toner as the base color and glaze to fill the pores and grain

Here is the process of graining in the finishing

•   The preparation of the surface.

The graining with glaze needs a smooth surface. The rough surface will hold the stain and make uneven layer of the stain and result for the uneven color. At the wood finishing we can apply the wiping stain for graining over the sealer, base coat or toner. The base coat or toner can be applied as the first step to block the uneven color of wood substrate to produce the even base color. Toner is the stain with some clear coat inside, then it will block the wood base color but will leave the grain and pores texture. It also can be used to make the light color to the dark wood color. While the base coat has higher solid content and it could cover the pores and grain. The base coat generally gives more plain and even surfaces without any pores and grain pattern. The m.d.f, resin or particle board particle usually already have the even and smooth surface, and we may be able to apply the glaze directly to the substrates. But it is still recommended to coat the substrates with sealer, toner or base coat to make better adhesion.

• The preparation of the glaze or wiping stain.

There are some things needs to be considered in the glaze preparation. The first is the glaze color.  Make sure the glaze has the proper color. Consider that the final color is a combination of color of the base coat, toner or substrate underneath and the glaze applied on it. Make sure the color combination between them give the right final finishing color.

The second thing is about the drying time of the glaze. Usually the brushing application need long time especially when we have to make special pattern. Set the drying time of the glaze to accommodate the application.  We may add some retarder at the glaze to let it slowly dry. 

• The graining techniques.

brushing the glaze

We need the proper brush to get the proper effect. If we want the smooth and even grain looked, then we can choose the brush with thick head and fine hair. But if the rough graining is needed we can use the rough and sticky hair brush.
Layer the glaze to the surface evenly, then stroke the brush from one end to the other. There are many effects can be made according to the thickness of the wiping stain, brushing techniques and the brush used. Make the grain looked effect as needed. Do practice on small panel to see the grain effect we need.

steelwool to lighten the glaze

Once the application is complete, let the wiping stain to dry. Check the grain resulted make we got the result as we need. We can wipe with steel wool if the glaze is to strong or add some more glaze if necessary. 

• Application of sealer or top coat.

The clear coating application is needed to protect the grain and pores effect resulted by the glaze. Make sure that the glaze is completely dry before we apply the coat of sealer or top coat on it. As the first coat, apply a thin sealer or top coat with dry spray or medium dry spray. Let it dry for awhile then continue with the wet coat application. The direct wet coat on a thick glaze or wiping stain is risk to get sagging problem.

Let the sealer dry, the do a good sanding on the dry sealer. Then apply a layer of wet coat of top coat as the final finishing layer.