We are Team 14, and in this Instructable we will be showing you how to make an ROV (remotely operated vehicle) submarine with PVC, some cheap materials, and some soldering.

Materials Needed:

1 10’ PVC pipe
4 elbow PVC fittings
1 PVC cross joint
4 PVC T joints
1 6” x 6” x 3” plastic tupperware container
Small wooden container, preferably with a lid.
40’ internet cable
3 motors
4 switches(one for emergency)
2 PVC socket caps
Water resistant silicon blend
Acetone
30 zip-ties
Soldering gun and solder
PVC cutter
Handheld drill
1 pack of shrink tube
Electrical tape

Step 1: Cut List for PVC

Cut List

2 x 1” pieces
4 x 1.6” pieces
2 x 4” pieces
8 x 5” pieces
1 x 8” pieces
2 x 0.3” pieces

Step 2: PVC Assembly

Measure and mark the different PVC cuts on the 10’ PVC pipe.
Cut the PVC lengths using the PVC cutter.
Gather cuts and PVC joints.
1. Label 4 elbow joints A-D.
2. Label 3 T joints A-C.
3. Label 1 cross joint “1.”
4. Label 4 1.6” PVC cuts 1-4.
5. Label 8 5” PVC cuts 1-8.
According to the first image, lay out the pieces labeled in the previous 5 steps.
Push the PVC cuts into the joints to match the first image.
Fit the tupperware container in the middle of the frame in the first image.
1. Label 2 elbow joints X and Y.
2. Label 1 T joint “2”.
3. Label 2 1” pieces “1” and “2”.
4. Label 2 4” pieces “3” and “4”.
According to the second image, lay out the pieces labeled in the previous 4 steps as well as 2 PVC socket caps.
Push the PVC cuts into the joints and caps to match the second image.
Attach the 8” PVC pipe to the bottom of cross fitting “1” in the first image and the top of elbow fitting “2” in the second image.
Double check that the PVC cuts are pushed all the way into the joints.

Step 3: The Motors

It’s assumed that all 3 motors are assembled and waterproofed on both sides, with wires coming out the backs.

Label your holes:
1. In the center of the top of cross piece “1” (in the first image).
2. Below T joint A (in the first image).
3. On the right side of elbow joint Y (in the second image).
4. In the center of the sides of the Tupperware container where the 1.6” pipes “2” and “4” connect to it (first image).
5. On pipes 3-6 (last image).
Drill the holes through the PVC.
Thread the wires from the backs of the motors through the holes.
Weave the wires from the motors to the hole where 1.6” pipe “2” connect to the Tupperware container and thread them into it.
Attach the motors to the PVC joints using zip-ties (third-fifth images).
The placement of the motors is used so we can go in different directions and the zip-ties keep the motors in place so they will not fall off.
1. In the third image the motor is placed so the sub can go forward/backward. The zip-ties are places in an x formation around the T joint to keep it in place.
2. In the fourth image the motor is placed so the sub will be able to move down and up. The zip-ties are wrapped around the top of the motor and on the bottom of the PVC, with one extra to keep them in place.
3. The fifth image has the motor going left/right. Use the 2 0.3” pieces to raise the height, because on its own the motor blades will hit the PVC pipe. The zip ties go around the pipe, 0.3” pieces, and motor to hold it in place.

Step 4: Wiring

Cut off 1’ of internet cable from the 40’ length and strip off the outer covering. This will be used for wiring the switches.
Thread the internet cable through the hole in the side of the Tupperware container (second image). It will be waterproofed later on as seen in the image.
Strip the outer covering of the end of the internet cable inside the Tupperware container using wire strippers, exposing the 6 colored wires inside.
Strip the end of each colored wire using size 28 on the wire strippers.
Solder one colored wire to each positive and negative wire of all your motors. It’s easier to put similar colors together (third image).
Wrap the soldered wires in electrical tape as seen in the first image.
On the other end of the internet cable strip the outside covering, leave a length of about 3” of each colored wire and pair them together based on which motor they connect to (fourth image).
On the end of each colored wire, strip off the end.
From the foot of internet cable cut off earlier, cut off 4” of two colored wires (again, put similar colors together to avoid confusion).
Strip off the ends and solder the two wires to one of the 3” of colored wires (in step 7).
Do this for all of the 6 colored wires coming from the end of the internet cable. The number of wires going out should now be 12.
Wrap the exposed soldered wires in electrical tape. The open ends will be attached to switches.

Step 5: The Switches

Note: Be careful not to accidentally touch the plastic casing of the switch with the soldering iron, because that will break it.

From the four wires that connect to one motor’s positive and negative wires:
1. Identify the two that connect to the positive and solder them to the top left and bottom right pins on a switch.
2. Identify the two that connect to the negative and solder them to the top right and bottom left pins on the same switch.
Repeat this for all three motors and switches. There should be 4 wires connected to each switch (first image).
Cut off 4” of two wires from the extra foot of internet cable (similar colors help) and strip both ends.
Solder one end of each wire to a middle pin of a switch. All 6 of the pins should be connected to a wire.
Wrap the exposed soldered wires with electrical tape so there isn’t danger of shorting out (second image).
Repeat for all 3 switches.
Take the wire connected to the middle left pins on the switches and connect their ends, and the wire connected to the middle right pins and connect their ends. These will become your positive/negative wires that connect to the power source.
From the end of the power source cable, strip off a little of the white covering one bunch (last image).
Cut off 4” of two wires from the extra foot of internet cable (similar colors help) and strip both ends.
Solder one end of each wire to a bunch of wires from the power source cable (third image).
Solder the other ends of the wires to the 2 positive/negative wire bunches that were made in step 7.
Wrap the exposed soldered wires in electrical tape, making sure that the soldered bunches aren’t touching.

Step 6: Waterproofing

On the ends of pipes “3” and “4” where they fit into elbow joints X and Y, wrap electrical tape to keep them airtight. Cut excess off the sides of the PVC pipe so that they will still fit into the joints (first image).
Wet a paper towel with Acetone and clean the spots where silicon will be applied.
When Acetone has dried, apply the water-resistant silicon blend to:
1. The inside and outside of the tupperware container where holes were drilled for wiring and where pipes connect (fourth and fifth images).
2. Where holes were drilled for the wires coming out of the motors (last three images).
3. The ends of pipes “3” and “4” (third image) where electrical tape was wrapped (first two images).

Step 7: Controller

Our controller is made from a miniature wooden chest from Hobby Lobby, which costed around $1.00. Other similar things will work, and feel free to use something different. The controller is only to keep the switches anchored and the put the wires in a protected box.

Make three marks where you wish your switches to be on the top of your container.
Drill 1/14" holes at the marks (first image).
On the bottom of the container make an opening large enough for all your wiring and switches to pass through. We first drilled 3 1” holes and realized that not everything would fit, as seen in the second image. The third image shows how we pulled all of the messy wiring through.
Fit the tops of the switches through the holes made in the top of the container in an order that suits you and close it. The switches should be much easier to use.

Step 8: Testing and Buoyancy

In order to balance the submarine, weights should be put into the Tupperware container.

Before putting the sub in water, plug in the power source and safely test the motors. They should spin in 2 directions and stay secure in their spaces.
Place the sub in water with the side with motors facing downwards. Make sure that the PVC has filled with water and that the sub is completely underwater before trying to move it around remotely. If the sub is still floating, add more weight to the container.