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Vacuum Assist For Dip Soldering

IP.com Disclosure Number: IPCOM000098105D
Original Publication Date: 1960-Feb-01
Included in the Prior Art Database: 2005-Mar-07
Document File: 1 page(s) / 12K

Publishing Venue

IBM

Related People

Radovsky, DA: AUTHOR [+2]

Abstract

In the process of dip soldering printed circuit boards it is found that application of a vacuum aids in producing more consistently good solder joints in through holes. By this technique the usual capillary lift is assisted by the vacuum to draw the molten solder up and completely around all component leads.

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Vacuum Assist For Dip Soldering

In the process of dip soldering printed circuit boards it is found that application of a vacuum aids in producing more consistently good solder joints in through holes. By this technique the usual capillary lift is assisted by the vacuum to draw the molten solder up and completely around all component leads.

1p.

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At present the two most widely used methods of dip soldering printed circuit boards are essentially as follows: 1. Flux the area of the board to be soldered and run the board over a wave of solder in a soldering machine. 2. Fix the board in a jig, flux the area of the board to be soldered and place the board face down on a solder bath.

Both methods permit only the face of the board to come into contact with the solder since when total immersion is used, sensitive components on the back of the board are damaged by the heat and the molten solder. Both methods rely on good capillary lift of solder in the holes and such capillary action is completely effective only when all through holes are completely plated, smooth and clean so as to induce a solid and complete through hole solder fillet. If the through hole plating is incomplete or if there is excessive roughness and surface contamination of the through hole plating, the result is usually an insufficient amount of solder in the holes and a poor or incomplete solder joint.

The purpose of this vacuum assist process is to insure consistent and complete dip solde...