Retrofit Kits for 3M Respirators -- common surgical masks can be used as filters in 3M 6000/7500 series respirators.

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The key components of these retrofit kits are the filters (please review the video). They safeguard the surgical mask sheets from large dust particles and aerosol droplets, keeping them as dry and clean as possible to prolong their effectiveness. ---------- HOW TO PRINT THE SIDE (INTERNAL) FILTERS WITH SIMPLIFY3D Since I am using Simplify3D, the parameters listed below are based on this software. However, theoretically, any slicing software that can control Top & Bottom Solid Layer and Infill Angle Offset of each layer will do the job. Note: Parameters marked with double-asterisk(**) are for reference only, as their values may vary depending on the printer. ---------- Key settings for layer height from 0mm to 0.4mm (first and second layer): Under Layer tab -- Layer Settings - Primary Layer Height: 0.2mm - Top Solid Layers: 0 - Bottom Solid Layers: 0 - Outline / Perimeter Shells: 2 Under Infill tab -- General - Internal Fill Pattern: Triangular - Interior Fill Percentage: 50% - ** Outline Overlap: 80% - Minimum Infill Length: 0.5mm - Infill Extrusion Width: 100% Under Infill tab -- Internal Infill Angle Offsets - Deg: 0 - Internal Infill Angle Offset: 0, 60, -60 - Print Every Infill Angle on Each Layer: Enabled Under Advanced tab -- Layer Modifications - Start Printing at Height: Disabled - Stop Printing at Height: 0.4mm ---------- Key settings for layer height started from 0.4mm: Under Layer tab -- Layer Settings - Primary Layer Height: 0.2mm - Top Solid Layers: 0 - Bottom Solid Layers: 0 - Outline / Perimeter Shells: 2 Under Infill tab -- General - Internal Fill Pattern: Rectilinear - Interior Fill Percentage: 50% - ** Outline Overlap: 60% - Minimum Infill Length: 0.5mm - Infill Extrusion Width: 100% Under Infill tab -- Internal Infill Angle Offsets - Deg: 0 - Internal Infill Angle Offset: 0, 15, 30, 45, 60, 75, 90, 105, 120, 135, 150, 165 - Print Every Infill Angle on Each Layer: Disabled Under Advanced tab -- Layer Modifications - Start Printing at Height: 0.4 mm - Stop Printing at Height: 3.6mm ---------- Key settings for layer height started from 3.6mm: From here you can print with general settings, just make sure top layer and bottom layer are enabled. Under Layer tab -- Layer Settings - ** Top Solid Layers: 5 - ** Bottom Solid Layers: 3 Under Advanced tab -- Layer Modifications - Start Printing at Height: 3.6mm - Stop Printing at Height: Disabled