Scrub Brush

This is a scrub brush for cleaning what ever it is that needs a little elbow grease. It costs a fraction of commercially available scrub brushes. In less developed regions cleaning tools such as a scrub brush are indispensable. This brush is also customizable allowing any size brush to be made easily for any application. It is printed using a bridging technique.^[1] This project was inspired by other fully 3d printable bristle designs^{[2][3][4][5][6][7]} . Note, some of these designs such as the broom are not OSATs as they are more costly to print than their commercial equivalents.

Bill of Materials

1. PETG or PLA filament
   1. PETG results in stronger more durable brush bristles
   2. PLA bristles tend to be more brittle
2. Customizable scrub brush files can be found at: https://www.thingiverse.com/thing:4025603
   1. Print using settings detailed in tech specs

Tools needed

1. MOST Delta RepRap or similar RepRap 3-D printer
2. Sharp knife, scissors, or other cutting implement

Skills and knowledge needed

• 3d printing slicing basics
• 3d printing bridging techniques

Technical Specifications and Assembly Instructions

1. Download desired .stls from thingiverse.com
   1. OSAT_scrub_brush_2.stl is a full size scrub brush
2. Cura Print Settings

   

   

   

   1. Set layer height to 0.3 mm if using uncostumized bristles
   2. 1.0 wall thickness
   3. 1.08 top/bottom wall thickness
   4. Enable "Print thin walls"
   5. Random z-seam alignment
   6. At least 20% infill
   7. 224 deg C default temp
   8. Set default print speed to 60 mm/s
   9. Combing mode: All
   10. Deselect "Avoid Printed Parts When Traveling"
   11. Disable support
   12. Enable bridge settings
       1. Min. bridge wall length: 0.5 mm
       2. Bridge skin threshold: 70%
       3. Bridge wall casting: 0%
       4. Bridge wall speed: 25 mm/s
       5. Bridge wall flow: 105%
       6. Bridge fan speed: 100%
   13. Watch first couple layers to ensure bristles are printing properly
       1. Try increasing bridge wall flow or decrease bridge wall speed if they seem disconnected from one side
3. The smaller test brush OSAT_scrub_brush_1.stl from thingivrese.com takes ~3 hours to print
   1. Use it to optimize the bridging settings
4. The fullsize brush OSAT_scrub_brush_2.stl from thingivrese.com takes ~7 hours 45 minutes to print
5. Cutting the brushes apart takes 10-15 minutes
   1. A sharp tool ensure fewer bristles will be broken during the process
   2. Avoid sawing motions to prevent breaking bristles
   3. Cut in a chopping motion with a sharp tool such as an exacto
   4. Cutting with the point up makes it easy to cut a strait line with a long knife
   5. If the bristles don't come out very even after cutting or if sections of bristles are sticking out use scissors to cut the bristles so they are level

Common Problems and Solutions

• Bristles are not printing right
  • Try scaling .stl to 101% to ensure it is sliced properly
  • Change bridge print settings
  • Make changes to bristle dimensions in .scad
• Bristles breaking during cutting
  • Try a sharper tool
  • Increase temp of print or flow of bridges to make bristles more secure
  • Try a different color or different filament (Any color PETG should work well)
• Brushes are hard to cut apart
  • Use a longer sharper tool
  • Some bristles may have become fused try changing print settings to produce better bridges
• Lots of bristles are falling out
  • Rub brushes together over a recycling bin to remove loose bristles
  • Increase temp of print or flow of bridges to make bristle more secure

Cost savings

• Print in PETG that produces two 120mm x 60mm brushes is ~$2.18
• Scrub Brush with Easy Grip from Walmart is $3.88 [1]
• $2.79 savings or a 72% savings

Benefited Internet Communities

• Spyder3D World [2]
• DIY [3] [4]
• OSAT [5] [6]
• r/Brooms [7]
• r/3Dprinting [8]
• 3d printing repositories [9] [10] [11]
• Cleaning [12] [13]

References