DIY: Laptop Cooling Pads

With gradually dropping laptop prices, most people prefer to have one at home or in the office simply because it offers the convenience of a compact computer. High-end laptops are quickly becoming desktop replacements and are in great demand for resource-intensive uses such as graphics design, video rendering, and even gaming. With prolonged and extensive use, a laptop tends to heat up faster and higher than the normal working temperature. A laptop used on a regular table has some drawbacks; the limited gap between the laptop base and the table doesn’t allow adequate airflow and, at times, creates a bad ergonomic posture for keyboard use. We show you how to make a simple and efficient laptop cooler in just under
Rs 700.

Requirements
For this workshop, you will need the following - an aluminum sheet (the size will vary according to the dimensions of your laptop), two or more 80 mm or 20 mm 5V or 12 V case fans, a 12 V DC power adapter in case of a 12 V DC fan, a 200 ohm potentiometer, a DC power jack, wires, rubber beading, super glue, and paint or stickers.

Note: We used a standard 15-inch laptop as an example for the dimensions. The fans used were 12 V DC brushless PC case fans.

Preparation
Firstly, cut out the appropriate size of the aluminum sheet you need for your laptop. Clean the surface of the sheet thoroughly using sandpaper. Then, according to the diagram given alongside, draw the accurate measurements on the aluminum sheet. These drawings will include lines for bending and drilling the holes.

Diagram - click for larger view

Drilling and bending
Once the drawing is complete, you will need to drill holes into the sheet wherever necessary. Using a punch tool or any sharp pointed nail, make dents where the holes need to be drilled. This is done to ensure that when you drill through, the drill-bit doesn’t slip.

Note: We have made numerous holes on the fan area for sufficient airflow. You can also cut a 120 mm hole and add a protective mesh or a fabric as a dust filter for additional airflow. When the drilling is complete, you will need to smoothen the entire surface to get rid of sharp edges formed due to the drilling. Use sandpaper or a metal file to smoothen the sharp edges and then polish the entire surface of the sheet for a final paint job (if required).

The next step is to bend the sheet. The bending process is a tough one, but made simpler

if you are careful enough and use a little tact. With the help of a metal scale or a sharp pointed nail, engrave (scratch) each bending line once or twice.

Note: The engraving needs to be done on the opposite side of the bend. Click for larger view

The engraving is done just to create a neat bend. To bend the sheet, lay the bending area on the edge of a steady table and using the other hand, gently apply pressure and bend it. You might require a mallet if you are using a thicker gauge of metal. Once the bending is done, the sheet should look like the letter ‘Z’ (see below). Finally, the pad can be personalized to your taste by either painting it or by sticking stickers, rubber sheets or fabric over it. We spray-painted our cooling pad for a plain black finish.

The circuit and finishing touches

While the cooling pad is drying, you can get the fan circuit ready. Solder the fans, potentiometer and the DC power jack in series according to the circuit diagram shown on the left. You can use 5 V DC brushless fans and have them powered using the laptop’s USB port, but as 5 V fans are difficult to procure, we have used two 12 V fans rescued from an old PC case. You can eliminate the potentiometer if you do not want to regulate the speed. Speed regulation is only beneficial to cut down the whirring sound when high speed fans are used. You can also add a switch if you need one. Additionally, you can also personalize the cooling pad by including a USB hub, speakers, lights or anything else that comes to mind.  

Click for larger view

Now install the power jack, potentiometer and the fans to complete the pad. Test the circuit to ensure that the fans are functioning properly. We have placed the direction of the fans so that it sucks the hot air out from the laptop. You can reverse the direction of the fans, but keep in mind that this might allow dust in from the bottom of the pad and into the laptop. Install an air filter if you do so. To finalize the product, line the edges of the sheet by pasting some rubber beading over it. This is to give the cooling pad a good finishing look and to provide good grip when placed on the desk. Finally, test your laptop on the cooler and adjust the angle of the bends so that the laptop is comfortably positioned for use.

Now that wasn't so hard was it?

You can make a laptop cooling pad with wooden planks, acrylic sheets, metal, or even hard cardboard. Ensure that whatever material you use is strong enough to hold the weight of the laptop. Using a soft metal such as aluminum is advisable as it is easily available, easy to cut and shape, and above all, it allows a good dissipation of heat.