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

The key parts of this set of retrofit kits are the filters (please check out the video). They protect the surgical mask sheets from large dust particles and aerosol droplets, keep them as dry and clean as possible to prolong their effective period.

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HOW TO PRINT THE SIDE (INTERNAL) FILTERS WITH SIMPLIFY3D

Since I'm using Simplify3D, parameters provided below are based on the software. But theoracially, 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, the parameter values may vary depending on printer.

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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

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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: Disabled

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HOW TO PRINT THE FRONT FILTER WITH SIMPLIFY3D

Since I'm using Simplify3D, parameters provided below are based on the software. But theoracially, 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, the parameter values may vary depending on printer.

ATTENTION PLEASE !!
If you're using a model named "Front_Filter", please delete it and download the new model "Front_Filter_v2".

WARNING:
The front-side exhaust filter reduces aerosol droplets that directly coming out from the front vent. Not a 100% perfect solution but sure better than none. Use it at your own risk.

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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: 4

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

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Key settings for layer height from 0.4mm to 3.6mm:

Under Layer tab -- Layer Settings

• Primary Layer Height: 0.2mm
• Top Solid Layers: 0
• Bottom Solid Layers: 0
• Outline / Perimeter Shells: 4

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

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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

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