Wood Finishing

Wood Finishing• What is wood finishing?• Why do we finish wood?• What are the steps to achieving a good finish?

Wood Finishing• Two steps to wood finishing– Sanding– Applying a chemical protectant (finish)

Sanding• Why do we sand the surface and edges:

• To remove machine marks• Smooth surface for good “feel”• Promote adhesion for finish

Sanding

• Removing Machine Marks

Sanding

• Making the wood “smooth”

80 Grit 120 Grit

Sanding

• Sanding should be done in at least three steps– 80 Grit (sub 100)– 150 Grit (sub 120)– 220 Grit (sub 180)

Abrasive Paper

40 gr, 80 gr, 150gr, 220 gr, 600gr

Sanding Tips

Sand with the grain

Don’t apply finish before 180 grit(see sander marks)

Don’t Quit too Soon (see machine marks)

Sanding Tips

• Raising the Grain– Final Step before applying finish– Raises the last tiny fibers so you can sand them off

Chemical Protectant• Wood is a porous absorbent material• Without finish it:– Discolors– Shrinks– Swells– Warps

Chemical Protectants• There are many different finishes, however

there is usually a “best” finish available for a given application.– Stain, Oil, Wax, Shellac, Varnish, Lacquer, Paint,

Enamel, Epoxy and Polyester Resin, and Water-Based Finishes (low VOC)

– Applying Finish