05 Application Grade1

7/28/2019 05 Application Grade1

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Paint School1

Application


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Paint School2

John applying the paint

Time is money !

John applies the paint in

the quickest possible

manner

Good workmanship is

important

Money can be saved in the

long run

Application: John_application1


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Paint School3

Important to open the tin correctly !

Remove all loose

particles from the lid

Loosen the lid

Lift the lid away

from the tin in such a

manner that the

contaminants do not

fall into the paint

Application: Open_dirtytin1


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Paint School4

Tools for mixing of paints

Always use mechanicalagitator to ensure proper

mixing.

Proper mixing will not be

achieved by a stirrer A stirrer may also contain

dirt and loose parts that

may contaminate the paint

and clog the spray

equipment

Cd-4930-57


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Paint School5

Mixing of two-pack paints

Component B is poured intothe component A (base).

Component B may have a

high viscosity. Make sure to

add all of it.Empty the tin !

Ensure correct mixing ratio.

Use mechanical agitator

The applicator is well

protected

Think of your health !

Cd-4930-58


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Paint School6

Mixing of a two-pack paint

Visual mixing control

The dark base makes

it easy to see when

the mixing is

complete

This is not easy to

see with a clear base

Poor mixing results

in poor protectiveproperties of the

paintApplication: Mixingcontrol1


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Paint School7

Airless spray:

Good

Paint brush:

Good

Roller:Poor, particularly for

the first coat

Methods for paint application


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Paint School8

Application tools.

Alternative orders.

Cd-4934-03

Alternative 2.

1. Coat: Brush

2. Coat: Spray

Alternative 1.

1. Coat: Spray

2. Coat: Spray

Rule:

Avoid roller on

the 1st. coat

Alternative 3.1. Coat: Brush

2. Coat: Roller


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Paint School9

Application by paint brush

Benefits

Good wetting of the substrate

Forces the paint into the surface

Better than roller on the first coat

Good on areas with poor accessibility

Limitations

Gives low film thickness, many coats required

Creates an uneven film

Application speed is slow


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Paint School10

Benefits

Application speed is faster than with paint brush

Good on areas with poor accessibility

Limitations

Poor wetting of the substrate

Never use for the first coat

May incorporate air and pinholesin the paint film

Gives low film thickness, many coats required

Application by roller


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Paint School11

Poor roller application technique

Ships bow

Roller mounted on top

of a long rod It is impossible to

control the applicationCd-4934-54


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Paint School12

Stripe coating will improve the life

time of the paint system

Use a good quality paint

brush

Work the paint well into the

substrate to wet thesubstrate properly

Welds, edges, notches and

areas difficult to reach by

spray must be stripe coated

Application: Stripe_correct1


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Paint School13

Stripe coating

Poor workmanship:

Stripe coating applied too thin Several holidays

Runs

Cd-4934-95


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Paint School14

Poor workmanship:

Stripe coated welding seam

Many holidays

The paint must be worked properly into the rough

substrate using several strokes with the paint brush.

Cd-4934-97


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Paint School15

Correct distance between spray gun

and substrate: (30-60 cm)

Correct angel (90)

Overlapping

(50% or cross application)

Paint application.

Rules when spraying


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Paint School16

Seek to keep the gun at a

right angle to the substrate

The distance should be between 30 and 60 cm. The optimaldistance will vary, among other things with wind,

temperature, pressure at the nozzle and viscosity of the paint .

Cd-4934-20


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Paint School17

50 %

OverlapOverlapping ensures

an even film thickness

Paint application.

Airless spraying with overlap


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Paint School18

Atomisation of the paint

Tip

Atomised droplets

of paint

Fan pattern

and width

Orifice


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Paint School19

Homogenous spray fan,

without fingering

The distance to the object is good

A spray fan with an angle in the range 60 to 80 degrees is

quite common when spraying flat, large areas.

Cd-4934-21


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Paint School20

Airless spray application is a very

fast way of applying paint

Spray application ensures a highproduction rate

Working in groups may speed

up the process even further

A good result depends on theskills of the applicator:

Keep the spray gun at a

correct distance from the

object Do not tilt the gun too much

Release the trigger before

stopping the stroke

Application: Spray_fast1


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Paint School21

Airless spraying.

Technique - small, complex unit

Spray can be successfullyused on small, complex

structures

Always start with the

complex parts of the structure Then, paint the plane areas

Keep the spray gun at a

correct distance from the

object Do not tilt the gun too much

Release the trigger before

stopping the stroke

Application: Spray_technique1


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Paint School22

Incorrect application technique.

Waving with the gun

Result:

Uneven paint film

Dry-spraying will occur

The loss factor will be high

The roughness will increase

Cd-4934-31


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Paint School23

Cd-4934-40

Effect of temperature,

distance and roughness (1 of 6)

Temperature

Paint + 10 oC

Air / steel + 10 oC

Distance 50 cm

Roughness 60 m

Result:

Very even surface, low roughness


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Paint School24



Temperature

Paint + 10 oC

Air / steel + 10 oC

Distance 100 cm

Roughness 175 m

Cd-4934-41

Increased distance givesincreased surface roughness


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Paint School25



Temperature

Paint + 30 oC Air / steel + 30 oC

Distance 50 cm

Roughness 58 m

Even at a relatively hightemperature a low roughness can be

achieve if the distance is correct

Cd-4934-42


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Paint School26



Temperature

Paint + 30 oC Air / steel + 30 oC

Distance 100 cm

Roughness 224 m

Increasing both the temperatureand the distance will result in an

increased roughness

Cd-4934-43


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Paint School27

Effect of temperature, distance and

roughness (5 of 6)

Temperature:

Paint + 30 oC

Air / steel + 10 oC

Distance 50 cm

Roughness 67 m

Correct distance and lowtemperatures give a perfect

paint surface: Low roughness

Cd-4934-44


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Paint School28



Temperatures

Paint + 30 oC

Air / steel + 10 oC

Distance 100 cm

Roughness 575 m

Too fast solventevaporation

Pin holes

Increased dry spraying

Long distance and high

paint temperature:

Cd-4934-45

W li ti t h i


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Paint School29

Wrong application technique:

Spraying of side bottom(1 of 4)

Reason:

Bad scaffoldings

Too long distance

Wrong angle

Dry spraying

Cd-4934-33

ResultA poor paint film:

Rough surface, pinholes, entrapped air.

W li ti t h i


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Paint School30



Too long distance Wrong angle

Dry spraying

Roughness increases

Cd-4934-34

Close up of surface:

Roughness increases

W li ti t h i


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Paint School31



Too long distance

Wrong angle

Dry spraying Cd-4934-35

Close up of surface.Magnified 8-10 X

Dry spray

W li ti t h i


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Paint School


Spraying of side bottom (4 of 4)

Too long distance

Wrong angle

Dry spraying

Very rough surface

Very porous paint film

Entrapped air

Cd-4934-36

Cross section of film.

Photo shows dry sprayed topcoat

05 Application Grade1

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