Introduction: RC Boat

About: 3rd year Mechanical Engineering student. Maker when possible and DIY culture lover. If something explodes, revise the diagrams! Check the "to be written" projects here! www.instagram.com/elbauldelma…

How to make an easy and fast RC Boat!

Step 1: The Plans

Here you have the boat plans in .dwg and .pdf format.

Download the .PDF plans if:

  • You don´t know how to use AutoCAD yet.
  • You don´t have a laser cutting or CNC machine.

Step 2: Materials Needed

Build the boat:

  • 3 and 5 mm plywood panels.
  • Coping saw.
  • Sand papers.
  • Polyester resin.
  • White glue.
  • Red, black and white paint.
  • Inkjet with white and decal sheets.

Electronics:

  • 15kg servo.
  • CNC Coupling.
  • 200A brushless ESC.
  • 115 mm Rudder Shaft.
  • HB 3650 Brushless motor.
  • 3 channel receiver.
  • FS-CT6B transmitter.

Step 3: Cutting the Pieces

  • Resize the .PDF as you wish for making a bigger or smaller boat. This model is 900mm long.

Tip: Under 550mm boats built with this plans tend to submerge when the lake is choppy. Be careful!

  • Print the pieces in white paper sheets and stick them on the 3mm panel.
  • Draw the contour of the pieces with a pencil into the plywood.
  • Dettach the papers and cut the panel following the lines you have done before.

Note: Don´t cut Half of Deck pieces until you have read Step 6.

Step 4: Hull Bottom

  • Glue the bottom pieces to the transom.

Tip: Sand down the inner parts of the bottom pieces before for creating a strong glued joint.

  • When the trasom glue has dried up, put the bow sections together.

Tip: Glue four semi-spheric wooden sticks as bilge keels. They will help the boat going straight at high speeds and rolling less.

Step 5: Hull Sides

  • Repeat the Step 3 process with the side pieces.

Notice the extra lenght added to the rear pieces for hiding the rudder.

Step 6: Deck

  • Join the Half of Deck paper sheets together with cellophane tape or draw the contour of one piece and later the other one with the same sheet.
  • Decide the cockpit size and cut the deck squared gap with a cutter. It may vary depending on the motor and batteries you are going to use.

Tip: Don´t make a big gap. The deck is straight until it reaches the yellow line. Exceeding it may cause problems when fitting the cockpit.

Step 7: Waterproofing the Boat

Polyester resin is a good sealer and adds extra strenght to the structure. Without it boats tend to dissasemble while crashing or after a few days touching the water.

  • Mix it with two catalyst drops in a can. Pour it inside the boat and spread it over all surfaces and joints.

Step 8: Motor and Rudder Mount

  • Attach the rudder shaft to the transom with four screws.
  • Cut another 5mm piece. The servo support must have four drilled holes.
  • Cable ties are a simple way of making a servo keep its place. Pass them through the holes.

Tip: Install a rubber bellow enclosing the servo bar. Avoid water to seep in!

  • Make a 5mm plywood motor mount. We are using the HB 3650 Brushless Motor.
  • Align the motor with the 4mm propeller axis and glue the mount to the bottom pieces.

Tip: Seal the axis and bellow with lithium grease. Without it water could flow inside the hull easily.

Accessories as trim tabs and turn fins can be bought or made using aluminium plates.

Step 9: Cockpit Brackets

  • Make an U structure using thin plywood sheets and squared sticks, the cockpit must fit in the gap.
  • Glue four screws to it. Their nuts won´t let the cockpit fly off while moving.

Tip: An easier yet effective way of sealing it is making the last picture´s four corner sticks frame. When you have the cockpit in place and the boat ready to sail, paste electrical tape on the cockpit-hull junction.

(The last picture is another boat, its Instructable will be ready soon!)

Step 10: The Cockpit

This model´s cockpit is made out of fiberglass.

  • Give shape to a polystyrene sheet using sand papers. This is going to be the mold.
  • Wrap it in plastic. This will help to separate the final pieces.
  • Add fiberglass strips soaked with resin all around the mold.
  • When dry, apply more soaked strips to put the upper and lower cockpit together.

(In the newest models I use another technique to make the cockpits, I will explain it soon)

Step 11: Add Some Extras

  • Add four squared sticks to the finished cockpit. Make sure they fit the lower U structure!
  • Drill four small holes to let the screws pass trought the cockpit.
  • Air intakes look nice and help to cool down the electronics and the motor. But be careful with the watertight!

Tip: For small models don`t make gaps for the intakes, just glue them to the wood panel.

Step 12: Closing the Hull

  • Glue the upper and lower hull together.
  • Sand down the projections of the upper hull.

Tip: If they are big, use a cutter first to help you.

Step 13: Decorative Spoiler

A non functional spoiler sounds weird.

These boats don´t run fast enough to make it work properly, so it is more like an extra accessory.

Step 14: The Boat´s Base

To avoid paint scratches or rudder dents a 5mm plywood stand should be built.

Tip: Make it waterproof or fix the pieces together with another glue. White glued parts tend to separate while in contact with water.

Step 15: Base Painting

White paint is used as base. The spoiler looks great in red.

Step 16: Extra Painting

The boat´s appearance will be better if we add extra colours as red or black.

Design your own scheme to make yours an unique boat in the world!

Step 17: Adding Decals

  • Search on the Internet logos you like or create your own ones. Paste them in a Microsoft Word tab.
  • Print them on decal sheets. You may have to change the inkjet settings before printing.

Tip: For Epson inkjets you should change the paper type to Epson Photo Paper Glossy or Premium Glossy. Results may vary depending on the sheet quality, the ink type and the printer model.

  • Apply some varnish layers to the sheet. If the ink makes contact with water, decals will smudge. Be careful!
  • Inmerse the decals in a plate with water one by one. Paste them to the boat and dry them with paper.

Step 18: Varnish the Model

Apply 2 or 3 varnish layers to the boat.

You can add more to the decal areas to be sure they are not going to move or smudge. Safety first!

Step 19: Ready to Run

  • Install the battery, the ESC controller and the receiver.
  • Put some cloths inside the boat to soak up water if cracks appear.

Our RC Boat is now finished!