3D Printed Foldable Shelves

This is a 3D printed foldable shelves I made for my research lab, B9 Forest Ecology lab.

Reasons why I do this:

+ Our lab usually processes a lot of soil samples. After being processed, these bags of soil was put near the window to let it dried out. However, the space is limited so I build this thing to increase the space that they can put the soil samples.

Softwares used:

• SolidWorks
• AUTOCAD
• MECHANALYZER

Total time to completed

• 99.75 Hours

For supplies you need the following things:

• 3D printer (Gigabot 3d printer, to print the frame of the shelves and Maker Gear M Series, to print other parts of the shelves)
• Filament (Because Syracuse allows students to use the school filament as long as the print is lighter than 150 gram, so we just need filament for the frames)
• Superglue
• AUTOCAD software
• SolidWorks software
• MechAnalyzer software

My idea was coming from this youtube video. I think this idea is really great because when you want to use, you just pull down the shelf, so it saves a lot of space and super convenient to carry around. However, I will make some modifications to it.

• You can clearly see the main mechanism in this shelf is Slider crank mechanism. Note that because we will use formula and calculation based on this mechanism.

The purpose of this step is just to draft the basic idea. So intensive calculation and careful design are not needed. As you can see I made some modifications:

• Have 2 shelves instead of 1 shelf like the youtube
• Also include the lock to prevent the shelves from falling down when we don't need it

This is the place I plan to place my shelves on. After taking pictures, I take some measurements of it.

• Basically the whole area has the length around 140 cm, so I plan to make the shelves around 55 cm.
• The width of the area is 76 cm, so I can make the shelves width around 20-40 cm if it is in used.
• The height of the shelves is around 50 cm because I want people to easily opens and closes it without tiptoe

So in this slider crank mechanism, there are 2 positions during the motion that you need to care, one is when the shelf made a 0 degree angle with the plane and 1 is when the shelf at 90 degree with the plane.

• Reason is that it's the lowest and highest point that the slider can travel, using the difference between 2 height, you can calculate the total distance needed for the slider to travel.
• The size of the slider you can choose based on your needs, it doesn't matter

After making calculations, it times for you to design the parts needed. Remember at this time, please note in mind some limitations in features of 3D printing. You will find a lot of confusion, however, my best advice is to design the frame first, then go for slider, and then go down to the actual shelves. By designing the bigger parts first, you can fix the variation in measurements of other parts. This approach I usually called Fixing free measurement variables.

• Above are 6 different designs you will need in this foldable shelves. However, note that, you might create different lock size just because of the dimensions you choose. Try to make sure you can use 1 part for many different places in design as it will be easy to manage.
• In my design process, I made a serious mistake by creating different sizes for 1 design, which takes much longer time to complete and also make it really tired to fix the design later.

Link to learn more about limitations in features of 3D printing: shorturl.at/ajPV1

Usually you will repeat step 5 and 6 a lot since you will discover a lot of flaws in your design. But don't worry, the more you do it, the more you learn about design for assembly. I repeat this step for 4 times at this stage.

At this stage, just print your parts as normal. One factor to consider while printing:

• 3D printing like other manufacturing process, has tolerances. Meaning if your part has length 50mm, the actual size might be 52mm or 48mm. Please be sure to ask your 3D printing technician about this. As it will affects Fittings of your parts during assembly.

Finally, just assembly parts together. Voila, you just complete the 3D printed foldable shelves.