Backbreeze the personal fan

The Backbreeze personal fan. 

This simple personal cooling fan clips onto the back of your shirt on the neck. It blows cool air down your back, keeping you comfy when the weather gets warm, you go for a jog, mow the lawn, or tackle any other toasty tasks. 

Amongst my photos (the model printed in gold) are some early prototypes as well as my initial sketch for my idea. This idea came to me when discussing the Sony Reon personal cooler with my wife. I thought that it might be fun to include some of those design process photos for you to enjoy. 
 

Some basic soldering skills may be required to build this project. I have included a hole for a switch and a compartment properly sized to hold a 9V battery. The lower voltage can still power the 12V 5015 fan, just not at full speed. It is enough to blow a gentle breeze down your back, though. 
 

if you did find a 12V battery, you could get more air flow. 

Hardware:

2 M2.5 X 3mm screws

2 m3 X 3mm screws

2 m3 X 18mm screws

1 Mini panel Slide switch, I used these

1 9V Battery connector, I used these

1 9V Battery, preferably lithium rechargeable, for most consistent voltage delivery and life

1 12V 5015 blower fan like this one, A 5V fan may overheat and is not recommended, a 24V may not spin fast enough and is also not recommended.

4 m3 x 5mm heat set inserts. 

Printing:

This model may be a little tricky to print if you don’t orient it properly. See the images of my slicer in the photos to see how I oriented it. 
 

Supports will be required as there are some large overhangs necessary to make the body all one piece… for now. I might be able to fix that with more time. Make sure there aren't any support structures generated inside the vent in the rounded portion of the model. They would be difficult to remove.

Printed in ABS for the base and Black galaxy PLA for the cover. These materials aren't important to use for this specific design or application, I think. It was simply what I had that I thought would look nice. 

Settings 

2 walls, 15% gyroid infill, .2 layer height

Assembly:

• Trim the little wire clip off of the side of the 5015 blower as it will impede the fit into the case. 
• Solder one of your wires on your 5015 blower fan to one of the outer terminals of the slide switch.
• Solder the corresponding colored wire from your 9V battery connector to the middle pin of the slide switch
• Solder the remaining free wires from the 5015 fan and the battery connector to each other.
• using a soldering iron or heat-set insert press. Install the M3 heat set inserts into the 4.2mm holes in the main body model. You will only need two to mount the 5015 fan inside the case, so only put them into the holes that correspond to the model of 5015 fan that you have. The other two inserts go into the holes near the bottom of the main body model and are for mounting the cover. 
• Install the fan and switch into the case, m3 screws for the fan and m2.5 screws for the switch.
• The battery can be installed into the connector and placed in the remaining space of the main body. Wires can be folded or wound and placed in the area between the switch and battery. Make sure none of the wires are on top of the battery to get a good fit when putting the lid on. 
• Be sure to check and remove any supports that are printed on the lid model carefully before attempting to install it
• Place the tab at the top of the lid into the corresponding slot on the main body. Do this by holding the lid at an angle from the main body and pushing it in as you lever it down. It should not be difficult to fit the tab into the slot. If you encounter any resistance, check for support material or defects on the print. 
• After placing the lid in the tab and it sits flush with the main body. Use two M3x3mm screws to secure the lid in place. 
• Done!

Your Backbreeze is now assembled and ready to use!

Please use caution when assembling this device. I take no responsibility for any mistakes or injuries made while assembling or running this electronic device. While my internet searching leads me to believe a 9V battery powering a 12V fan should be safe, you must take the responsibility on yourself to check. Stay cool, have fun!