▼This page was part of an MTU course MSE4777 OA and MSE4777 OB/MSE5777/EE4777/EE5777: Open-source 3-D printing

Please leave comments using the talk page. The course runs in the Fall semester. It is not open edit.

▼Preliminary Student Design Warning

This page is a preliminary student design and has not been vetted. Care should be taken to read critically and weigh the evidence. Remember non-tested and vetted designs should not be relied on, especially in matters of health and safety.
Reason:

• At the current scale this device is not practical for this application

With two small printed parts and two springs, my corn crusher can do what its name implies: crush corn. This device is supposed to replace the mortar & pestle by making it easier and less labor-intensive to grind corn into flour. The contributes to solving OSAT Goal 2: zero hunger

Bill of Materials

• Openscad files and STL's on Thingiverse
• 2 small springs to fit into the circular holes of the housing. Diameter should be no greater than 12 mm. The uncompressed length should not be larger than 35 mm.
• 1 3D printed housing
• 1 3D printed pedal

Tools needed

• MOST Delta RepRap or similar RepRap 3-D printer

Skills and knowledge needed

• N/A

Technical Specifications and Assembly Instructions

Print settings for both pedal and housing:

• Layer Height: 0.2 mm
• Shell Thickness: 1.0 mm
• Bottom-Top thickness: 0.6mm
• Fill Density 20%
• Print Speed: 100 mm/s
• Print Temperature (PLA): 200 C
• Flow: 100%

1. Print the housing.

   

2. Print the pedal (Note: there is corn dust on the pedal from previous use).

   

3. Insert the springs into the housing.

   

4. Insert corn into the middle square hole of the housing. Insert the pedal into the housing. Begin crushing by placing the device in both of your palms and squeezing the pedal into the housing. Alternatively, place the crusher on the ground and use your feet to push the pedal down.

   

Cost savings

• Approximate cost for housing: $0.30
• Approximate cost for pedal: $0.20
• Approximate total cost: $0.50
• A primitive mortar & pestle would be made out of stone or wood; it would not be bought. Rather than money being saved, it would take less time to grind corn.

References