Costing new products - Qty of solder paste

Are you running high volume. If yes then what you propose may be relevant. If however you run low volume - lots of changeovers then your wastage/transfer will be equal if not greater than the amount put on the boards. Enclosed systems like DEK Proflow will greatly reduce this wastage.

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Richard,

take a given volume and weigh it. For your parts you have already determined the aperture opening and stencil thickness and that gives you the volume for each lead of the component. This way you should be able to determine the amount of paste used for each board. But realize that only a part of the paste you need to produce a board actually sticks to the board. Depending on your printing, cleaning and handling process yopu will see that more or less paste is needed which is not found on the later product.

A good approach would be to determine the average consumption for a given board (or if you like for a component) taking the amount used over along period and the number of boards ( or used components ) and than calculate for a new product. In my experience the amount of used paste depends on the batchsize and the equipment and processes used and that for a good calculation the wastage should be taken into account.

Good luck

Wolfgang

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