What are the methods of applying solder paste?
Even and accurate spreading of the solder paste is crucial for high-quality connections on the PCB. Over the years, there have been many ways to apply the paste: from manual dispensers, through screen printing to automated dispensers. Here we will discuss the most popular ways to apply solder paste.
Applying solder paste using a screen printer
Screen printing is still the most popular method of applying solder paste. Companies dealing with the assembly of PCBs have a choice of screen printers that allow three modes of operation: manual, semi-automatic and automatic. Simple printers for manual screen printing are the cheapest. However, they require high precision and manual setting of the sieve and squeegee templates, as well as the supervision of the application itself. Semi-automatic screen printing is limited to setting the plate in relation to the template. The most advanced screen printers offer us automated processes where the operator feeds the plates and then removes them after applying the solder paste.
Manual dispensers for the application of solder paste
These types of devices are used only in small plants due to the low purchase costs. The process of applying paste in the case of a manual dispenser is very time-consuming and requires the operator to be very concentrated and precise. Due to technical limitations, manual dispensers are only used on large rasters and with a small number of elements.
Automated solder paste dispensers
The modern electronics industry is constantly looking for better and more efficient solutions. In the case of printed circuit boards with a large number of elements, the screen printing technique often becomes insufficient. Therefore, specialized automatic dispensers adapted to the precise application of solder paste are used.
The advantage of this solution is the possibility of modifying individual aspects of the work. Automatic dispensers use a wide range of dispensing heads that allow you to set the speed, accuracy, and repeatability, which is especially important when producing a large number of the same printed circuit boards. The process of applying the paste is quite simple, however, it should be supervised by a trained operator. The downside compared to screen printers is, of course, the high cost of buying an automatic dispenser.
Which method of applying solder paste is the best?
There is no doubt that in the era of more and more advanced technologies, continuous miniaturization in electronics, automatic dispensers are the best. They enable fast, very precise, and at the same time repeatable work with minimal operator involvement. Therefore, large production plants rely on this type of equipment. Nevertheless, advanced screen printing technology is still very popular and is considered a very efficient method of applying solder paste. The advantage of an automatic screen printer is, of course, a much lower price.