First week at the SPQR Lab: Electronics Bench and Rework



On the first day of my work at SPQR lab, the lab members spent three hours on reworking two USB breaker boards. Looking at the figure below of oxidized soldering tips, I found that many tips could not hold heat. The job should have taken than less than 10 minutes with proper soldering tips and solder. The lab has advanced oscilloscope and lab bench digital multimeter, but misses on having inexpensive rework equipment such as proper solder, flux cleaner, and vice. In this blog post, I will discuss inexpensive but very handy tools which make reworking much easier.



Completely Oxidized Soldering Tips

The most necessary tool for a solder rework is soldering station. Many people would have seen standalone soldering pencils, but these soldering pencils lack gauge to control the temperature. Therefore, a soldering station with either analog or digital gauge is necessary. Fortunately, a decent soldering station costs less than $150: Weller WESD51 Digital Soldering Station. SPQR lab has the exact same model of the soldering station. Furthermore, miscellaneous items such as solder wicks, a flux pen, flux cleaner, high quality non-magnetic, anti-acid tweezers, and solder are all inexpensive items that aid in rework. Solder wicks are used in reworking PCBs, wiping off solder bridges on IC pins, and clean excess solders on pads. A flux pen helps solder adhesion to the PCB.
To alleviate the unnecessary work and stress, I suggested Connor, PhD student at SPQR lab, that we purchase thinner multicore solder and clean leads. These are inexpensive but necessary soldering equipment that will make the soldering and rework much easier. While soldering and rework are not the focal activity in either research or development, having proper equipment along with adequate skill helps researchers and engineers to focus in more important tasks such as testing and development. Soldering and rework shouldn’t be a hinder to the students’ engagement in engineering.

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