The following is a tutorial on how to build a reliable, water tight, drive unit for your Aquabots. The "Aquapod" is made from easily obtainable parts and is cheap to construct. The Aquapod can easily be changed from this generic example to suit your particular application. Read the entire tutorial before you begin. You are encouraged to print this tutorial out and place it in your BEAM files for future reference. No commercial use, please. If you build something using these techniques, just give me a mention.


1  Walkman motor
2   vending machine containers (small)
1   bag of 3 weighted floats
1   plastic straw thingy (from Radio Shack)
1   prop (not pictured)


wire cutters
X-acto knife w/extra blades
super glue
60 sec. epoxy glue
tooth picks

All but the prop and red straw can be bought at Walmart. I guess you could buy the red straw too, if you buy a can of WD-40.


Take one of the floats and depress the plastic piece on one end. Snip one of the hooked ends off of the brass wire with your wire cutters. Take the float completely apart. Take the three parts highlighted and throw the rest in your parts bin. The two plastic parts and the weight are all you need. You can take another float apart and keep only the weight. At the end of this tutorial, you will need both weights.


Take one of the vending machine containers and drill a hole with your X-acto in the exact center of the dome. There is a small depression in the plastic that you can use as a guide. Use your X-acto to scrape thin slivers off of the hole until it is large enough for the end of the larger tube with the flange to fit through fairly snugly.

Next, take your X-acto and cut the tube in half. There is a slight transition here in the tube. It gets a fraction larger in diameter from the center up to the flange. Find this line and cut there. Insert the smaller tube to check for length. You want the larger, outer tube to be slightly shorter than the smaller, inner tube.


Now, take the large tube and center the cut end on the bearing and motor shaft. Put the small tube inside to help keep everything lined up. Place two small drops of super glue on either side to hold the shaft in place. Be careful to use only a small amount of glue. Check to make sure you haven't glued the two tubes together. Remove the inner tube. Let dry.

Now, mix a small amount of epoxy glue and cover the bottom of the shaft. Spread the glue over to the two mounting screws to help lock everything together. Make sure there are no gaps where the shaft meets the motor.


Push the motor into the vending container that you drilled the hole into. Push it up snug and straight. Add a couple of small drops of super glue between the motor and plastic to hold it in place. Let dry.

Mix up another small portion of epoxy glue and make a donut shaped seal around the edge of the shaft and container with a toothpick. Be careful. Don't get any glue inside the shaft, yet cover the edge of the shaft thoroughly.


You're almost done! Glue your prop to the smaller tube. Now, just push the tube with the prop into the inner sleeve and press onto the motor shaft. This may be a snug fit. If the tube is to tight, take your X-acto and ream the inner tube out a little. Do this slowly and a little at a time. Check the fit and repeat if needed. The smaller shaft may be sanded as well. I bet you are wondering what happened to the red straw. Some of these Walkman motors have thinner shafts. If your's does, then cut a small piece of the straw and insert it inside of the prop tube. Now, slip this onto the motor shaft. At this point you have two choices. You can place a solar engine and cap inside of the second container. The two weights are glued inside of the second container as well. Put them toward the front bottom of the inside of the container. This will help balance the pod. Seal the two halves together with a bead of epoxy around the point where the edges meet and let the wires protrude from the seam for hook up to your solar cell. Seal the solar cell leads and glue it to the top of the pod with epoxy. The second method is to simply cut the second container of it's excess room and glue the pieces together with the motor leads coming out. More than one of the Aquapods can then be hooked to a brain in a different location on your Aquabot. Remember to cross the motor leads if you want the pod to move forward with the prop at the rear. Red to negative, black to positive. If you make the prior version, just add some floats to make the pod positively bouyant and some hydrofoils to make it dive and you're in buisness. Or put legs on it and make it rise up from the bottom. This same method can be used on gear motors as well if the propper shafts are found. Remember to place a couple drops of oil between the prop shaft and the inner sleeve. This will help keep your water tight seal. Not to much! Let it creep into the space between the shafts by capillary action. You now have a water tight motor pod. There are endless ways that it can be used to move your creations through the briney deep. Good luck, and write me if you have any questions.


Copyright 1999, all rights reserved, Jim Mullins DBA Studio One.