## 2 Materials and Methods
The file formats available are STL (the standard file format for AM) and FCStd (FreeCADs file format, which enables parameter changing). Printing instructions can be found in Appendix A. The design of the clip system was modelled according to the Fused Deposition Modeling (FDM) Design Guidelines [38] that ensured the ultimate tensile strength of at least 33 MPa according to the datasheet of ABS (acrylonitrile butadiene styrene) material that was used for printing [39]. It should be noted that FDM is a trademark registered by Stratasys and thus, a subset of material extrusion (ME). Any material extrusion-based 3D printing system capable of appropriate polymers (e.g., ABS, PC, etc.) can be used to fabricate the design. The uPrint SE Plus ME printer from Stratasys was used to print the clips with ivory ABS filament. Minimum layer thickness and assembly clearance was set as 0.254 mm. The parts were printed in \"upright position\" for maximum strength in the X-Y planes following guidelines [38]. The printing times were 2 h 44 min for the hose holder clip and 4 h 13 min for the redesigned cyclone sampler holder clip. For the purpose of testing the clip systems, a prototype harness was fabricated and used for testing. Figure 1: FreeCAD renderings of the fastening mechanism on the sheath (**top left**), releasing mechanism on the slider (**top right**), clip system from the back (**middle left**), clip system with hose holder tool from the front (**middle right**), redesigned clip system for the cyclone sampler from the back (**bottom left**), and redesigned clip system for the cyclone sampler from the front (**bottom right**). Due to the nature of the measuring done in different environments from food industry to mining industry, cleaning the clip systems between different environments is important to avoid contamination. The hose holder clip was cleaned by wiping and immersing in an 80% ethanol-water solution. One cleaning cycle lasted for approximately 55 s, which was reiterated 50 times. The mechanical properties of additively manufactured ABS are well established that range from 21 to 39 MPa in tensile and 38 to 41 MPa in compressive strength [40; 41; 42; 43; 44; 45; 46]. Low-cost desktop printers have been used to produce parts with these proprieties reliably for mechanically taxing applications from bicycled parts [47] to surgical tools [48]. The known issue of additively manufactured components is the lower tensile stress values in the Z-direction (upwards). The designs of the tensile and/or compressive specimens in the aforementioned literature ensured that no stress concentration was built up around the fillet of the specimens due to raster termination. This was accomplished either by completely removing the fillet and adapting a flat rectangular specimen according to ASTM D3039 [49] and/or improvising the specimens of ASTM D638 [50]. Likewise, the current design of the clip system ensured that no rasters were terminated at edges of the clip system that were loaded with the most stress during usage. Furthermore, fatigue strength of ABS is recorded as 17.8 MPa with \(1.9\times 104\)  
Figure 2: (a) The \(5+1\) input parameters of the parametric clip system equipped with a hose holder; (b) the 5+1 input parameters spreadsheet of the parametric clip system equipped with a hose holder; (c) three variants of the parametric clip system equipped with a hose holder. cycles [51] and 40% of the ultimate tensile strength in the order of thousands of cycles [52]. The stresses induced in the clip system during fastening or releasing can be considered as negligible due to the nature of light weight tooling that is used for this study. Nevertheless, after the cleaning test, the clip system was then put through a durability test similar to those on medical diagnostic equipment [53] consisting of mechanical testing of the clip system through sliding the slider to sheath on and off repeatedly when it was attached to a harness. This procedure was executed 5000 times.