I decided to build a device that could travel along the water at my control and was very stable that I could put a gopro on and take above and underwater photography

...So that is exactly what I built

Hopefully this instructable will guide you through the steps that went into creating this

Note that this was my first project involving RC so forgive my minimal knowledge of the subject

Step 1: Why a Catamaran?

A catamaran is "a multihulled watercraft consisting of two parallel hulls of equal size."

This means that the craft is much wider than a monohull vessel, allowing it to be more stable in the water

It also doesn't need a keel, so it can be in much shallower water

It doesn't need ballast to help it balance, so it is much lighter

Step 2: What You Will Need

I made the catamaran from good ol' 1/2" PVC, used standard RC electronics and RC Boat parts as well as the gopro with a corresponding clamp mount. I added pool noodles onto the pontoons for extra flotation (this proved unnecessary but it looked cool to me!)

The frame:

6x 1/2" PVC 45 degree
2x lengths of 1/2" PVC
4x 1/2" PVC "T"
4x 1/2" PVC end caps
A small plastic tub for the electronics
4x 1/4" galvanized bolts to hold the tub onto the frame (washers and nuts as well)
2x pool noodles and zip ties to hold them to the pontoons

The electronics

An RC receiver (I stole mine from an old RC I had lying around)
the corresponding transmitter for that receiver
I used an hpi 15 turn brushed motor for this project and corresponding ESC I got from ebay for $15A
servo for the rudder
Batteries and charger (I ran two NIMH batteries in parallel for longer run times

The other hardware

A "U" clamp of corresponding size to the diameter of your motor
A thin steel rod to use as a prop shaft
Orange paint

The Boat Stuff

An RC boat prop (got mine from amazon)
A small plastic surface to act as a rudder (and the means to connect that to the servo)

Step 3: Put It Together

I'll mash the actual construction of the thing into one step because it's not complicated at all

I don't expect you to follow exactly what I built (I wouldn't!) so please make your own variations and let me know about them in the comments

What I did in a nutshell:

First, glue together the PVC frame as shown and paint it if you want
Attach the plastic tub to the frame with the nuts
Drill a hole for the prop shaft to go through and holes for the "U" bolt motor mount
Attach the motor inside the U bolt and tighten it, connect the motor shaft to the prop shaft and put the prop on
Install the servo and the push rod for the rudder along the prop stabilization bar (Pic 3)
Connect all the electronics together
Attach pool noodle flotation device with the zip ties
Drill a hole for that receiver's antenna and you're ready to roll (float)

Oh, and put that gopro on there somewhere

Note: If you are using your catamaran in water that is not clear, paint the prop orange that way if it gets detached somehow, it will be visible (it has actually happened to me)