Why M2.5 and M4 Stainless Steel Bolts?
To meet the project’s objective of standardising hardware, we have selected M4 and M2.5 stainless steel bolts as the primary components, together with stainless steel inserts and nylock nuts. We chose M4 over M3 due to its significantly greater holding strength—approximately 200–300% higher—especially for lengths exceeding 60 mm, where torsional stress becomes problematic. This substantial increase in strength justifies the slight increase in diameter. Furthermore, M4 nuts integrate more reliably into 3D-printed cut-outs, requiring only about 0.2 mm tolerance. This simplifies precision fitting and reduces assembly issues, ensuring greater consistency and accuracy across all hardware and components throughout the project.
Tools and setup
By standardising on M4 and M2.5 hardware, we reduce the variety of components required, which significantly decreases storage demands. Fewer bolt sizes and nut types mean fewer assembly tools are needed, reducing complexity during both storage and use. This also minimises the need for different driver heads, spanners, or torque tools, as a single set of tools can handle most of the assembly tasks. When setting up, we no longer need to bring an excessive range of tools or hardware, allowing for lighter and more compact toolkits. This makes on-site assembly faster, reduces the chance of missing essential tools, and improves overall reliability during installations.