Immerse Tin Powder Instructions

45 grams for 0.5 litres

Description

A powder for making an immerse tin solution for plating a smooth even surface of tin on copper circuits at room temperature. A tin plated circuit protects the circuit from oxidisation and greatly improves solderability. Although this product is intended to be used for tin plating copper tracks on printed circuit boards a large number of hobbyist have and do use this solution to tin plate various metals with great success.

Mixing

Although used at room temperature, the powder must be dissolved with hot (50°C-60°C) distilled water.

Using the 45g for 0.5 litres put 0.12 litres of cold water into plastic bottle and then fill to the 0.5 liters mark with nearly boiling water from a kettle. Screw the cap back on tightly and then shake vigorously. Leave for 5 minutes and then shake again.

When the power is all mixed in, allow the solution to cool down to room temperature. It is now ready to be used and for best results should always be used at this temperature.

Usage

Firstly it is important that the copper is perfectly clean and free from oxidisation. After the photoresist has been stripped from the circuit and it has been washed and dried it should be scrubbed clean with a PCB scrubbing block. Then bang the board and rub with a hard clean cloth to remove any particles left by the scrubbing block and immediately immerse in the tin.

With fresh solution, after 20 seconds a coating of 0.2 microns will be plated.

0.8-1.0 microns after 5 minutes and 4-5 microns after 3 hours. When the initial area of copper has been plated the tin will begin to plate tin on tin. It is therefore uneconomical to leave a board immersed for too long, overnight for instance.

For optimum results the board should be immersed in cold water as soon as it is removed from the tin. This will stop the tinning process; the board should then be washed in hot water (40°C+) and rubbed dry with a clean cloth before air drying with a hair dryer or other hot air blower.

Capacity and Shelf Life

0.5 litres of fresh solution will plate 15-20 complete copper Eurocards with 1-1.5 microns of tin or 5 Eurocards with 5 microns. As an average etched circuit has 30% copper a figure of 50-65 Eurocards respectively is a more accurate figure. The solution will have up to six months shelf life if stored in an air tight plastic container.