July 7, 2010

Water Cooled Laptop

Many laptops tend to run very hot, and as a result their tiny blower fans have to work hard to stop the computer from overheating.  Simple ways of fixing this include taking some compressed air to the heatsink, or reapplying thermal paste.  But this is a far more interesting solution.

Repaint and Watercool Your Laptop


Materials and Tools:

- 2 1/4" X 3" X .2mm copper sheet
- About 5 feet of 5/16 OD X 3/16 ID clear vinyl tubing
- Lots of 5 minute epoxy
- Small pump- I used this one 
- 2X nylon barbed T's, 1/4 inch
- 2X nylon barb to screw adapter, 1/4 inch
- Electrical wire
- Electrical tape
- USB cable
- Stock Athlon CPU heatsink
- J B Weld
- Small Motherboard Northbridge heatsink
- Thermal paste
- Spray paint for plastic, your color of choice
- Clear glossy acrylic spray
- Medium grit sand paper
- Laptop LCD hinges
- Assorted screws
- Dense 5/8 inch or so thick foam
- Masking tape
- Block of wax
- Modeling clay
- 3/4 inches of thin PVC pipe
- 6 inches of 1/4 ID 3/8 OD vinyl tubing

Tools:

- Hot glue gun
- Screw driver
- 2 clamps
- Rotary tool with cutting and brushing heads
- 6 volt battery
- Pliers
- Scissors
- Wire strippers
- Box cutter/ craft knife
- Drill
- Drill Press
- 5/16 inch drill bit
- Metal cutting oil
- Goggles
- Soldering Iron + solder



And obviously, old laptop:

Materials and Tools

Pump:

Materials and Tools

LCD hinges:

Materials and Tools

The first step is to repaint your laptop.  Before you actually go to painting your laptop, there are a few things you need to do to prepare it. First of all, completely disassemble your laptop, including the screen. Remove the plastic covers from all the drive bays. Separate any buttons from the main body of the laptop. When you are taking it apart, it is helpful to keep screws next to their corresponding parts. Also remove anything stuck to the body of the laptop, such as stickers and rubber feet.

Preparing the Laptop for Painting

Next you will have to tape up all the spots on the plastic you do not want painted over, like internal parts and screw holes. After you've done that, wash the casing with a cloth and rubbing alcohol and lightly sand the plastic, to help the paint get a grip on it. If your laptop has some sort of indented logo on the back, fill it with epoxy.  To paint the laptop, I used white glossy Krylon for plastic. Unfortunately, it did not turn out glossy, because the paint had some sort of chemical reaction with what was already on the laptop. Spray 10 or more coats to get a decent finish.

Painting the Laptop

Painting the Laptop


The next step is to add an image of your choice to the back of the laptop.  I chose to use a picture of one of our pet chickens.  Print the picture out in the best quality you can, and fix it to the back of the laptop screen with spray on adhesive.

Adding an Image to the Back

To seal in the picture, spray the laptop with at least ten coats of glossy acrylic spray.  Be careful not to let it pool on the image, or the paper will wrinkle.  Once all the pieces are dry, reassemble the laptop.

Glossing your Laptop

Glossing your Laptop


The next step is to construct the waterblock.  The waterblock is the part of the watercooling system that transfers the heat from the CPU to the water in the loop. I designed my waterblock so the input and output were facing the same direction, because there was a lot of space in the laptop that way. then I made a clay model of the top half of the waterblock. To turn your clay piece into plastic, you need to make another mold, of the outside of the clay model. Put the clay model up side down in a container just wider than the clay model. I made mine with cardboard and duct tape. Then pour melted wax around the clay piece, until is is completely covered by 1/4 to 1/2 inch of wax. When The wax has hardened, scrape out the soft clay in the middle. Then fill your wax mold with quick drying epoxy. When it is dry, you should be able to peel off the wax. Then use a brush on a rotary tool to clean any wax or clay off your epoxy waterblock piece. Sand the epoxy piece smooth.

Clay:

Constructing the Waterblock

Constructing the Waterblock

Wax: 

Constructing the Waterblock

Resin:

Constructing the Waterblock

Now we need a way for the tubing to be connected to the block. I bought two barbed nylon adapters. One end has threads, and one is barbed. Using epoxy, glue the threaded ends to the inlet and outlet of the waterblock.

Constructing the Waterblock, cont.

The last part of the waterblock that is needed now is the bit that actually interfaces with the CPU.  I made the base of this out of a 2mm thick sheet of copper.  Right above the spot the CPU will sit, I mounted an old Northbridge heatsink with thermal paste and JB weld.  The fins of this heatsink fit into the cavity in the resin mold.  I then bonded this to the top half of the block with more epoxy.

Constructing the Waterblock, Final Step

Constructing the Waterblock, Final Step

Constructing the Waterblock, Final Step


The next step is to build the radiator.  The radiator is the piece of the watercooling loop that transfers the heat from the water to the air. Most commercial radiators are too large for use in a laptop, and their fins are too closely spaced for them to work well passively. The only solution is to build your own.  Because of their shape, the stock AMD heatsinks are perfect for this. With a dill press, drill 4 evenly spaced 5/16 inch holes through the base of the heatsink, and then saw the heatsink in half with a hacksaw, parallel to the holes. Using J B Weld, glue the two halves of the heatsink end to end so the holes line up. To make a U turn at one end of the radiator, insert two 1 inch pieces of the tubing into the holes, with their ends cut at 45 degree angles. Cut an other piece of tubing, with both ends at 45 degree angles, and glue it between the two protruding bits of tubing to connect them.

Stock heatsink:

Building the Radiator

Drilled and cut:

Building the Radiator

Glued

Building the Radiator

U turn:

Building the Radiator

To mount the radiator, ut the hinges from a laptop LCD so the are as long as the radiator is wide. Glue them onto the bottom of the radiator so that the screw holes on the hinges line up with screw holes on the bottom of the laptop.  Ten simply screw the radiator to the laptop.

Radiator Mounting

Radiator Mounting

Radiator Mounting

The next step is to rout all the tubing.  It is best to have long, slow curves, as opposed to sharp corners, because they impede flow less.

Routing the Tubing

The next step is to fill the loop with water and run it to check for leaks.  The two T joints in the loop are for a water inlet and an air outlet. Ideally, water goes in one, and the air goes out the other. For this to actually happen you need the water you are filling it with to be under some pressure, so it forces out the air. I built a device to do this out of a milk jug. Cut a hole in the bottom and in the cap, and glue a piece of tubing into the hole in the cap. To fill it, attach the tube to the inlet in the loop, and fill up the milk jug. Once there is some water in the loop, run the pump so the water circulates and the air bubbles are filtered out.  Then seal the inlet and outlet.

Filling the Loop

Since the pump I used was designed to run on 2-6 volts, I figured the 5 volts provided by the USB ports on the laptop would be a good way to power it.  To make an unobtrusive USB power connector, you will need to cut the end of a USB cable so it is only a centimeter long. Then solder 10 inch wires to the +5volt and ground pins on the USB end, which are the outer ones. Plug in your new USB dongle, and run the wires through the laptop to the battery slot, where the pump will be.

Powering the pump

To actually attach the loop to the laptop, start out by mounting the radiator with the glued on attachments. Then mount the pump in the battery slot. The waterblock will be a little trickier. First apply some thermal paste to the CPU. Wedge dense foam around the block to keep if from moving side to side. To keep it down, screw a piece of metal diagonally across it between two screw holes on the bottom of the laptop.  Then wire the two pump wires to the two USB Wires.   If your laptop has a good lay out, it may be possible to integrate screw holes directly into your waterblock, which would be ideal.

Attaching the Watercooling Loop

Attaching the Watercooling Loop

Finally, add larger foam feet to the bottom of your laptop.

Feet

Feet

Feet



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