Engineering news
Cutting tools with variable helix angles promise reduced cutting forces
Commonly used multiple flute cutting tools feature the flutes at a helix angle. Invariably this helix angle is uniform across the flutes. The function of the flute helix angle is to elongate the duration and length of contact between the tool flutes and the workpiece, hence promoting a smoothing of the cutting process.
Previous reported papers have suggested that the use of tools with non-uniform helix angles would result in reduced cutting forces and the suppression of chatter. However, it was thought that the manufacture of tools with non-uniform helix angles would be extremely difficult.
This paper analyses the geometry of non-uniform helix angle tools. Following this sample, tools were manufactured to show the feasibility of using this analysis to manufacture sample tools using rapid prototyping techniques.
A cutting force model was also generated for non-uniform helix angle tools, which showed significant calculated cutting force reduction – compared with tools of a fixed helix angle – of 40-60% depending on the depth of cut.
Title: Geometric definition, rapid prototyping, and cutting force analysis of cylindrical milling tools with arbitrary helix angle variations
Authors: Chigbogu Ozoegwu and Peter Eberhard
Proc IMechE, Part B, J Engineering Manufacture
2022, Vol 236(9) 1232-1246
Seven questions focus research thinking
The correct initial focus for proposed engineering research ideas is critical to achieving the maximum benefit from the research project. Most engineering students are well trained in the technical skills to solve commonly known problems in research projects. They are not trained in a systematic critical thinking process however, and this prevents the generation of creative ideas leading to a successful outcome.
This paper proposes a critical thinking process called IDEA, based on seven questions. In this process the questions are asked, requiring answers so that engineering students can be trained to scrutinise their research ideas and maximise the benefits.
The seven questions are:
Background: Why are we doing this?
Problem: What are we trying to solve?
Current status: How was it done by others?
Challenge: Why didn’t others do it well?
Innovation: What is your new idea?
Method: How do we get it done?
Verification: What criteria are to be used to verify?
Three typical case studies were presented, together with the answers to the questions and further questions. The case studies from the authors’ university showed excellent results and proved that the IDEA process is effective in innovation development.
Title: A seven-question based critical thinking framework for cultivating innovation talents in engineering research and its implementation perspectives
Authors: Yingguang Li, Changquing Liu, Ke Xu, Xiaozhong Hao and Shaochun Sui
Proc IMechE, Part B, J Engineering Manufacture
2022, Vol 236(9) 1157-1168
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