Touch-up painting (solvent)

A Zn-Al based paint is recommended for touch-up of weld zone and cut ends.

Examples of touch-up paints

Paint name	Manufacturer	Type of paint	Color
Roval Silver	Roval Corporation	Zn-Al based	Silver
Zinky special	Nippon Paint Anti-corrosive Coatings Co., Ltd.	Zn-Al based	Silver
O-well Mekki Silver (ZAM® color)	Nihon Ruspert Co., Ltd.	Zn-Al based	Silver

・Notes
1. Details of touch-up paints including their proper use, quality haracteristics, and compatibility with environmental regulations should be checked with respective makers.
2. In some cases, painting is not possible over touch-up paints. Be sure to check beforehand.

Corrosion resistance of weld zones after touch-up

Satisfactory corrosion resistance can be obtained by touching up the weld zones in an appropriate manner.

Appearances of touch-up painted areas after combined-cycle corrosion test

Thickness: 2.3 mm, coating weight: 85/85 g/m2

0 Cycles Paint: Zn based — 0 Cycles

100 Cycles Paint: Zn based — 100 Cycles

150 Cycles Paint: Zn based — 150 Cycles

200 Cycles Paint: Zn based — 200 Cycles

Paint: Zn based

0 Cycles Paint: Zn-Al based — 0 Cycles

100 Cycles Paint: Zn-Al based — 100 Cycles

150 Cycles Paint: Zn-Al based — 150 Cycles

200 Cycles Paint: Zn-Al based — 200 Cycles

Paint: Zn-Al based

Reference scale: 20mm

Sample of welding method

Welding method: CO2 arc welding
Joint shape: Butt welding

Painting method

Pre-treatment: Wire brush
Degreasing: Organic solvent
Painting: Brushed on
Drying: 60°C, 10 min
Film thickness: Approx. 40μm

Test conditions
JASO M609-91

Test conditions

Corrosion resistance of cut edges after touch-up

Additional corrosion resistance can be obtained by touching up the cut edge.

Appearances of touched-up cut edges after combined-cycle corrosion test

Thickness: 2.3 mm, coating weight: 85/85 g/m2

0 Cycles Paint: Zn-Al based — 100 Cycles

100 Cycles Paint: Zn based — 200 Cycles

Paint: Zn-Al based