GROUP ASSIGNMENT
1- design a machine that includes mechanism + actuation + automation
2- build the mechanical parts and operate it manually
3- document the group project and your individual contribution

Software Used

SketchUp,Fusion 360, RD Works V6, AutoCAD, Adobe Illustrator, Google Chrome, Sublime Text, Photoshop, Git
        

Tutorial Used

CoreXY CNC Plotter
Build a CNC
Fab Academy Week 14 - Mechanical Design

Files used:

Case file for bottom case 38cmx40cmx5cm .SVG                      Download
Case file for top sandbox 40cmx42cmx5cm .SVG                      Download
Machine Design group page

Walkthrough

GROUP ASSIGMENT:

Design a machine (mechanism+automation), including the end effector build the passive parts and operate it manually document the group project and your individual contribution

Throughout the course we have been trying to decide which machine we should build, some options we had in mind were:
- Chocolate Printer
- Ceramic Printer
- Plasma cutter
- Augmented Reality Sandbox

We really liked the printers but decided upon something that could be built and used immediately and consistently with a local material: sand.


CORE XY SAND PRINTER

Sand Plotter - CoreXY

Materials:
- 4steel rods 50cm long from a recycled 3d printer
- two motors for x and y axis
- arduino microcontroller with motor driver shield
- 3d printer
- acrylic 3mm transparent
- wood 1/4" plywood - fine grain sand
- strainer
- metal ball
- magnet
- 3d printer board Melzi Version 2.0


Individual contribution Building a container to house the sand.

We watched tutorials of how an xy printer works.



We downloaded available files to study how the machine would work.



We prepared a list of materials and divided the work up among the students.



I used http://www.makercase.com to layout the two boxes measuring 38x40 and 40x42cm.




Next I laser cut the boxes and we assembled them together.


We sourced some of the components from local providers.



We had an old 3D printer that hadn't gotten any use in the last year and decided to take it appart to salvage what we could.



Lucky for us the printer had 6 pulleys that would work perfectly for the project.



We were also able to repurpose the motors and rods that would hold the magnets and bearings for the belts.

Conclusion

This week was a rapid prototyping course as a team and I really enjoyed it. I was able to contribute building the case and housing for the machine, which consisted of 2 stacked boxes. The bottom case would be to house the motors and components and the top one would be to house the sand. Each one had design considerations to discuss like structure, thickness and transparency of the material. As a team we decided to use 3mm acrylic so we could easily show visitors how the plotter worked. I designed the files on makercase.com and cut them on our laser. We assembled them as a team and determined which other components we needed for the project. During the week I went to several stores in the city to buy magnets and a printer belt that we would attach to the motors. At a gear and bearings shop there were belts but they were only 1' long and we would have to join them if we needed it to be longer. They suggested a printer megashop up the street, but when I arrived they said that I had to know exactly which printer model I needed the belt for. I picked a model of the 50+ they had, but when they brought it and took it out of the box to show me it had been corroded from being in storage for more than a year. They hadn't sold any replacement belts, so when they told me the price would be $180 for a 2m belt I checked amazon and saw them for less than $25 for 10'. The store was willing to let me purchase it for $20.