How to make a ROV!
Step #1 From your spool of 18 gauge primary wire, cut between 11 and 21 three inch strips of wire. You will only need 11 for the ROV, but it is good to have extras. Using the wire cutter, strip about ¼ inch of insulation off of each end of the wires. Apply an electrical fork terminal (16-14 AWG) to each end of the wires. With the crimping tool, secure the fork to the wire. For additional security, solder each connection between the electrical forks and the wires. Follow the instructions included with the soldering tool. Set the wires aside for now.
Step#2 Drill three ½ inch holes in the lid of your conduit box in a triangular pattern as shown. Now drill one 5/8 inch hole and two additional holes in the front of the conduit box as shown. The size of the two smaller holes will depend on the thickness of your tether cable and power cord.
Step #3 Open your three (ON) OFF (ON) toggle switches and remove the rings and nuts. Insert the toggle switches through the lid of the conduit box so that they align as shown. Secure the toggle switches to the conduit box by placing the rings and nuts on the top of the switches and tightening with the wrench and pliers. If it looks like there are any gaps in the lid, apply a bit of hot glue around the base of the toggle switched to ensure that the lid is waterproof.
Step #4 Loosen the screws on the end of each toggle switch. Now, using six of the wires you prepared earlier, attach them to the toggle switches in a cross ways manner as shown and re-tighten the screws. You may have to reposition the wires at a later time if they prevent you from closing the conduit box. If so, just loosen the screws and bend the wires out of the way.
Step #5 Gather three more of the prepared wires, three fork terminals, and one female push on terminal. Attach an electrical fork terminal to the end of one of the wires Now, twist the other end of that wire together with the end of another wire. Attach another electrical fork to this junction. Twist the free end of this wire together with a third wire and attach another electrical fork at this junction. Finally, attach the female push on terminal to the free end of the third wire. Each of these connections should be reinforced with the soldering iron. The finished product should look like this.
Step #6 Take two more of the prepared wires and three electrical fork terminals. Attach an electrical fork terminal to the end of the first wire. Twist the other end together with the other wire and attach an electrical fork to the junction. Finally, attach another electrical fork terminal to the free end to the second wire. Again, each of these connections should be reinforced with the soldering iron.
Step #7 Using the longer set of wires and starting with the end nearest the female terminal, attach the first electrical fork to the left side of the first toggle switch (the one at the top of the triangle) as shown. The female terminal should be left dangling Attach the next fork terminal to the left side of the second toggle switch as shown. Finally, attach the third electrical fork terminal to the right side of the third toggle switch as shown
Step #8 Now, grab the other set of wires. Begin by attaching the first electrical fork to the right side of the first toggle (at the top of the triangle) as shown. Next apply the second electrical fork to the left side of the second switch as shown Attach the final electrical fork terminal to the right side of the third toggle switch.
Step #9 Insert one end of your six wire cable tether into one of the smaller holes on the end of the lower half of the conduit box. Strip off about three inches of the outer shell of this cable. You may need to use scissors or a razor blade to do this if your crimping tool does not work. If so, slowly cut around the cable and try to avoid cutting any of the inner wires. Strip each of the six interior wires about ¼ - ½ inch. Apply an electrical fork terminal to each. Solder these connections.
Step #10 Loosen the bottom two screws on each of the toggle switches to allow a second electrical fork. Now, separate the six wires into three different pairs of two. It does not matter which two colors you pair, but write down the pairings as it will be important later. Attach the first pair of wires to the bottom of the first switch as shown. Attach the second pair of wires to the bottom of the second switch as shown. Lastly, attach the third pair of wires to the bottom of the third switch
Step #11 Take the heavy duty speaker cable and cut off about ten inches to use later. Insert the long piece into the second hole in the bottom of the conduit box. Separate the two wires by tearing them apart about 3-4 inches. Strip the end of each wire about ¼ inch. Attach a 16-14 AWG ring terminal to one of the wires and a female push on terminal to the other wire. Solder each of these connections. Remove the screw from the right side of the toggle switch at the top of the triangle. This terminal will already have a wire connected to it, but add the ring terminal and then re-attach the fork terminal and tighten the screw
Step #12 Unscrew the fuse holder and insert the fuse by pushing it into the bottom as shown. Re-screw the fuse holder. Remove the nut and washer from the fuse Insert the fuse through the 5/8 inch hole, replace the nut and washer and tighten into place. There are two metal connections on the fuse, make sure the one on the side of the fuse is facing up, towards you.
Step #13 Find the end of the power cord with the female push on terminal and attach it to the connection on the end of the fuse as shown. Now, attach the other female push on terminal from the first series of wires to the connection on the top of the fuse. Solder both of these connections and once cool, wrap the connections in electrical tape to prevent them from touching anything else. You may now close your conduit box. Be sure to screw the top on very tightly as to ensure that the box is waterproof. Remember that you may need to bend some wires out of the way or readjust some of the connections If there are any gaps between the wires and the holes, apply a bit of hot glue to ensure that the juncture is waterproof.
Step #14 Locate the free end of the two strand power cord. Again, separate the two wires by pulling them apart about three inches. Now strip each wire about ¼ inch. Attach the solder-less banana connectors following the instructions on the package. These will be left alone for now.
Step #15 Now it is time to assemble the propellers and attach them to the motors. Line up all of the necessary parts. You should have a prop shaft, drive dog, electric flex hex, and a propeller. If you look at the prop shaft, you will notice that there is a part of the shaft that is threaded. You will need to remove this portion of the shaft. There are two ways to do this: first, you could use a hack saw to cut off this portion, secondly you could use the bolt cutter part of the crimping tool to remove this. If you opt to use the bolt cutters, be very careful not to pinch your hands and watch for flying parts. Next, take the flex hex and unscrew the two pieces and loosen the screw at the bottom with an Allen wrench Insert the prop shaft into the larger portion. Slip the second piece of the flex hex onto the prop shaft and tighten. You will need to use two pairs of pliers to really tighten this connection. Now, slide the propeller onto the prop shaft with the slotted side pointed up. Finally, slide the drive dog onto the prop shaft so that the notches are pointing down and fit into the slots on the propeller. Place the screw into the appropriate hole and tighten with the Allen wrench. In order to attach the completed propeller ensemble to the motor, you will first need to remove the plastic disk at the end of the motors. Slip the end of a screw driver or other flat object under the disk and ease it off. Place the propeller on the motor as shown and tighten the small screw with the Allen wrench. Set the prepared motors aside for a moment.
Step #16 Grab the other end of your 6-wire tether. Strip off about three inches of the outer shell as you did before. Strip each of the six inner wires about ½ - ¾ inch as before and put them in groups of two, remembering to pair the same colors together as you did in step 10. Take the three motors and twist the two attached wires together as shown. Now, strip the ends of attached wires about ½ ¾ inch, if not already stripped. Twist together each pair of wires from the motor with a pair of wires from the tether. A pair of needle nose pliers is very helpful in this process. Once each set of wires are twisted, solder the connection so that they do not come apart. When all three sets of paired wires are connected, wrap the connections in electrical tape to prevent the wires from touching one another.
Step #17 Wrap the entire collection of cords in several layers of electrical tape to ensure that the area is waterproof. Using the hot glue gun, apply a bit of glue to the end of the tether where the motor wires enter the electrical tape tube. This will waterproof the entrance of these wires. Secure a zip tie to the tube just below the entrance
Step #18 Cut six 3 inch pieces of PVC pipe and drill a small hole in one end of each pipe. To help prevent slipping, wrap each motor with a few layers of electrical tape as shown. Attach one 3 in. PVC pipe to the opposite side of each motor using the zip ties. Loop the zip tie through the drilled holes, around the motor, and tighten
Step #19 Find the 10 inch piece of power cord you cut off and set aside earlier. Split each end about 3 inches. Strip each wire about 1/4 inch To one end of the power cord, attach two extra large ring terminals as shown. Solder these connections. To the other end, attach the female ends of the banana connectors. This piece of cord will be used to attach the ROV to the battery source when you are ready.
Step #20 At this point, you are almost ready to start building your ROV frame. But first, it would be helpful to make a note of which switch controls which motor. Attach the ring terminals to the battery; red is positive and black is negative. Plug the banana connectors into their appropriate female terminals. Turn on the first switch and make a note of which motor it controls. Place a piece of colored electrical tape on the switch and its corresponding motor. Do the same for the other two switches and motors.
Step #21 This step is up to you. Now that your three motors have a piece of PVC attached to them they can fit into your frame anywhere. Build yourself a custom frame from your PVC pipe and position the motors to best improve mobility. There are many different designs that will all have ups and downs, it is your job to find the perfect shape. It is easiest to use the two rear switches/motors for forward thrust, reverse and turning and use the third motor for lateral control.