Teaching Students How To Troubleshoot, Repair, and Maintain Magnetic Stirring Hot Plates Using Low-Cost Parts or Repurposed Materials

Abstract

Considering the large number of magnetic stirring hot plates that are damaged or unused in chemical laboratories, this Technology Report presents guidelines for students to be able to diagnose problems, and repair and maintain magnetic stirring hot plates using common and low-cost parts, or even repurposed materials. In addition, this paper presents a control board for stirring or heating with a circuit that uses the triode for alternating current BTA08, as well as various suggestions for refurbishing, maintaining, and replacing parts. Guidelines are provided for diagnosing equipment and conducting a cost analysis to determine the economic viability of proposed maintenance and repair approaches.

Design-Based Learning Framework for Introducing Factorial Experimental Design and Lab-on-a-Chip Separations in an Instrumental Chemistry Laboratory

“…Part of the impetus for developing this exercise was our belief that open-ended, design- and discovery-based learning closely models the true nature of chemical research, where troubleshooting and experimental failure are critical elements of the process often overlooked in traditional laboratory experiences. More, troubleshooting in the context of this type of peer-led team learning has been shown to promote cognitive flexibility, critical thinking, and communication skills and is especially prevalent in instrumental analysis courses. − Though pedagogically valuable, this format of teaching and learning in the chemistry curriculum will almost always lead to unexpected outcomes, experimental challenges, and, sometimes, student frustration. However, the design-based learning framework of this exercise explicitly and intentionally forefronted student team ownership in the troubleshooting process since the team was central to the very design of both the instrument (device) and the experiment.…”

Understanding the Specific Technical Requirements Needed for Successful Transitioning to a Workplace and the Chemistry Undergraduate Course Syllabi: A Case Study

“…However, given the demand for this skill set, students can be trained to develop basic maintenance skills, which can be transferable to more complex equipment in the workplace. De Paula and Ruggiero attempted to teach students about simple maintenance skills through servicing and tearing down commonly used laboratory tools. Using this strategy, students can develop a valuable skill, and in the process, universities can keep the cost low by servicing rather than replacing simple laboratory tools.…”

“…Universities can learn how to incorporate these skills into the curriculum in either mandatory or optional courses. , This will help students prepare appropriately for jobs and become more competitive in the employment market.…”

Robust, Efficient, and Economical Magnetic Stirrer: A Device Based on Pulsed Width Modulation, Built Using Mainly Recycled Parts

“…Our aim in this project is to build a simple but effective magnetic stirrer using mainly recycled parts that can be obtained from commonly generated e-waste material. A few variations of self-built stirrers have been reported in the literature, , as well as low-cost innovations from several other types of lab equipment. , …”

“…While the existing self-built stirrers , are undoubtedly worthy contributions to the scientific community, we believe our unit is different and especially attractive due to (i) the low cost (∼US$17.50 which is lower than those in the literature) involved which makes it affordable for laboratories even in developing countries to have access to, (ii) the simplicity in its hardware and circuit design making its construction an easy task, (iii) the parts which are readily available through recycling or from an electronics shop, (iv) a lighted user interface which is convenient for its practical use and enhances its aesthetics to that of a store-bought unit, and (v) the compact and very neatly housed structure which allows comfortable fitting into fume hoods/work benches. Some designs utilizs open-source platforms such as Arduino; however, our approach demonstrates circuit building from first principles.…”