Wood Finishing Applications Flashcards
Oil stains are divided into Two types what are they
Penetrating Oil
Pigment Oil
How do you apply Oil stains
Manually by brushing or wiping.
How does Penetrating Oil and Pigment Oil get there colour
Pen Oil-Soluble aniline dyes
Pig Oil- Non soluble pigments (Earths)
When might you consider using a NGR Stain
If you want to top coat right away they dry immediately
If you need to stain over other finishes to even out colour or reduce contrast.
What happens to NGR Stains in sunlight
They may fade
If there is solvent present in a top coat it may cause a NGR stain to?
May cause NGR Stains to bleed
What do NGR stains use as a vehicle
Alcohol and other solvents
Basic Description of natural varnish?
Transparent, Hard, protective finish
When would you choose a varnish
When a Durable finish is required
What is a Natural Varnish a combination of ?
Drying Oil (Typically Linseed Oil)
Resin (Natural Resin or Gum such as Shellac)
Solvent (Turpentine or paint thinner)
What’s the drying like for varnish
Some are slow some are faster drying and some are completely waterproof
Types of synthetic topcoats?
Varnish
Polyester
Polyurethane
Most durable top coat?
Varnish
Describe what a polyester finish on wood is like?
Exceptionally hard and Durable clear finish.
Very high gloss and look wet
What do polyester finishes consist of?
Liquid finish mixed with a catalyst and many types are meant to be warmed before spraying.
Polyester Pot life
15 - 20 minutes
Types of spraying equipment
Conventional
Airless
Air assisted airless
High Vol Low Pressure HVLP
How is fluid delivered in an airless spray gun
They a piston or pump to deliver fluid to the spray gun tip
Atomized by forcing it through a small tip at high-pressure
What are airless guns more commonly used for
Painting rather than for applying clear finishes
Would you use an airless for a clear finish?
Not ideal
Airless guns are suited for fine finishing?
No
To much product is delivered and particles are to large
What do Air-Assisted airless systems combine
Features of conventional and airless systems
Transfer efficiency higher in air-assisted airless then conventional?
Yes
First step in surface prep
Surface evaluation
Use light to identify deficiencies
Incandescent light is superior to fluorescent light for inspection.
How do you identify invisible contaminates such as glue and scratches?
Mineral spirits
brush on
Types of Stains
Water
Oil
Alcohol (NGR)
Pros and Cons of water stains
Pros:
Brilliantly colored
Non fading
Deep penetrating
Clear tone
Cons:
Raise Grain
Difficult to apply evenly
Before staining what should be done with end grain
Wipe a coat of clear stain base or stain conditioner
Minimizes absorption of the stain into the porous area.
What is bleach in wood used for?
Remove stain defects
Lighten wood
Types of bleach Available?
Oxalic Acid
Chlorine (Calcium Hypochlorite and Sodium Hypochlorite)
Sodium Hydroxide and Hydrogen Peroxide
Commercial wood bleach kits are a combination of?
Sodium Hydroxide and Hydrogen peroxide
Application procedure for bleach?
Fiber bristled brush working bottom to top to minimize potential for streaks.
Name the spray guns label top to bottom left to right p
Air Spray
Airless
HVLP
Air-Assited airless
What defect is being shown in this photo
Fish eye
