HexH2O Pro V2 – Build Guide

Posted on August 15, 2017

We have put together the following build guide for our HexH2o Pro V2 customers. You are free to build the HexH2o in whichever way you wish, however it is recommended you follow the guide as closely as possible in order to obtain the most from your purchase.

This tutorial is based on using DJI E800 motors and T-Motor 40A Air ESCs. Please note that DJI’s ‘smart ESC’s’ will not work on the HexH2O Pro V2.

TIP: Read this guide IN FULL before you start.

This guide is based on a full build process from a HexH2O Pro V2 kit. If you have purchased a RTB (ready to build) some of these stages may already be complete (depending on the parts you have purchased).

1 Remove rear hatch and electronics tray from the body.

2 Fit the rubber grommets into the eight holes in the top of the frame. The two smaller grommets go into the outside holes.

tip – placing the grommets into hot water before fitting will make the job easier.

3 Apply the hook velcro to either side of the body (this will attached to the foam buoyancy aids later)

4 Fit the motor cables

You will need 18 x 18AWG cables for the motors (supplied as standard with our RTB machines). Cut each of the cables to 26″ long. Pass the motor cables through the six larger grommets (three per hole). Tie the cable ends together inside the body (this will make it easier when you come to solder the cables to the MT60 connectors).

5 Fit the breather tubes

Slide the clear breather tubes through the two smaller grommets on the top of the body, ensuring the tubes are pointing forwards.

6 Top plate assembly

Important: The plate with the 4 counter sunk holes is the bottom plate – the counter sunk holes should be facing the top plate once constructed:

Take note of the positioning and orientation of the arm fittings as pictured, mount the fittings on the TOP plate (no CS holes) using the supplied M2.5×6.3 screws and 2.5mm hex key.

Note that one face of the plastic boom clamps has a filed face, this edge must be facing the bottom counter sunk plate once constructed.


Note: Ensure you use blue thread lock on all fixing screws.

Fit the M3 boom clamps bolts through the top plate using tape to hold them in place.

Fit two 0.5mm washers to each bolt.  then fit the boom clamps followed by a further two 0.5mm washers.

Fit the bottom plate ensuring the counter sunk holes are facing the top plate.

Finally fit the remaining M2.5×6.3 screws (using blue thread lock) and the supplied M3 nuts (do not fully tighten these at this stage).

7 Fitting the carbon arms

The two arms that only have holes drilled at one end are fitted into the metal (non folding) boom clamps ensuring. Slide the non drilled end into the clamp, alight the end of the boom with the inside clamp – do not tighten the clamps at this stage. 

Fit the remaining booms, and fix into place using the supplied black bolts (using blue thread lock).

8 Fitting the top assembly to the body

Fit the supplied 20mm stand offs using the 1mm washers and 10mm M3 bolts

The order for fitment is: bolt, washer – body – washer, stand off

– ensure you use blue thread lock on the bolts. Tighten the bolts from the inside using the supplied 3mm hex key.

Place the top assembly in position, pass the motor cables and breather tubes through the centre hole in the top plates.

Important: At this stage you will also need to pass the N3 GPS cable through the centre hole in the top plates and down through the body via the pre cut hole. 

Next open out the arms into their locked position. Fit the four counter sunk screws (used to secure the top assembly to the main body) using the 2.5mm hex key and blue thread lock. 

Thread the motor cables down each arm, leaving approx 4-5” hanging out the end of the arm.

Ensure the cables running through the fixed arms, are positioned behind the breather tubes.

Slide the breather tubes clamp over the breather tubes, leaving approx 1/4” overhang, cut the end of the tubes to square of the ends.

Then fit the foam baffle over the clamp and secure with the supplied cable tie, then pull the tubes back through the body – leaving the baffle as pictured.

9 Fitting the GPS holder

Cut 4 strips of 3M tape (supplied with your N3 flight controller) to secure the bottom cover of the 3D printed GPS holder.

– use two strips per side. Ensure the opening in the GPS mount is facing forward.

Using the round 3M tape (supplied with your N3 flight controller), stick down the N3 GPS module.

Take one of the supplied clear grommets and cut down to the first ridge:

Fit into the GPS top cover – glue around the base of the grommet from the inside of the top cover.

Using marine grade sealant, apply a bead around the rim and opening of the GPS top cover.

Fit the top cover in place and ensure the opening is adequately sealed.

10. Fitting the GPS cable cover plate. Thread the supplied M3x10 screws through the cover plate. Apply marine grade sealant to the underside of the plate and fit into position, passing the screws through the body. Fasten in place using the supplied M3 nuts.

11 Motor assembly

Cut the 3.5mm bullet from the motor cables and discard.

Fit each motor to the carbon motor mount plates using four of the M3 x 4.5 screws supplied with your E800 motors (these come with thread lock pre applied to the screws).

Note the orientation of the motor cables.

Fit the motor and carbon plate to the motor mount using the supplied M2.5×6.3 screws (ensure you use blue thread lock). Note the carbon plate is mounted on the same side as the stainless steel bolt head.

Fit each of the motor assemblies onto the carbon arms.

IMPORTANT ensure you fit the correct rotation motor to the correct arm as per the diagram below.

Strip back the motor cables.

Fit a 1” length of 4.8/2.4 heat shrink tubing over one end of the cable. Entwine the cables together as pictured in preparation for soldering.

We strongly advise you use solder flux and a high temp soldering iron in order to get a good quality solder connection.

Once the cables are soldered together we advise using ‘Liquid Tape’ (a form of ‘brush on’ insulation.) to seal the connection. Then slide the heat shrink over the connection and apply heat to seal.

Once complete carefully pull any excess cable back through the body, ensure you leave enough cable slack by the folding arms so as not to damage the motor cables whewn opening/closing the arms. 

12 Fitting the legs 

Align the leg braces on the underside of the body. Each brace should be recessed approximately 1” – 1.5″ as pictured

Drill the fixing holes using a 4mm drill. Apply a small bead or marine grade sealant around the hole on the left brace.

Fit the leg braces using the supplied nylon nuts and bolts.

To fit the legs, simply push them into the slot in the side of the brace.

Trim down the bolts as required.

Finally seal the screws from the inside.

13 Preparing the ESCs and wiring loom

We recommend using the T-Motor Air 40A ESC for the HexH2O PRO.

Cut back the heat shrink to expose the ESC heat sink just enough to allow you to fit one of the supplied external heat sinks.

Score the surface of both heat sinks and bond in place using a high strength glue and allow to cure.

We recommend using the Tarot Hex (8 point) distribution board for the HexH2O PRO. 

Open up the distribution board and drill a hole in the bottom plate (as pictured) to allow for a M3x8 fixing crew (supplied with the E800 motors) to sit flush in the hole. This will later be attached to the distribution board stand off as shows in the pictured example below:

Solder the ESCs to the distribution board.

Solder MT60 (or connectors of your choice) to the ESCs. The cable order is not important at this stage, so they can be attached in any order.

By default in order to keep the cables tidy we solder them on as pictured;

Solder 6” 12AWG cable cables to the board – solder a female XT90 to the other end. This will be used for the main power to the drone.

Solder 4” of 16AWG cable to the board – solder a female XT60 to the other end. This will be used to supply power to the N3 flight controller.

Solder 4” of 18 AWG cable to the board – solder a female MT30 (or connector of your choice) to the other end. This will be used to supply power to the Fan.

Solder4” of 18 AWG  cable to the board – solder a female MT30 (or connector of your choice) to the other end. This will be used to supply power to the X3 camera.

Apply a layer of hot glue to the underside of the distribution board.

IMPORTANT this is required in order to avoid any risk of the board shorting on the mounting screw.

Put the wiring loom to one side and move to the next step of the build.

14 Sealing the cables

You will now need to seal the motor cables, breather tubes and fixing bolts from the inside of the body.

Apply a liberal amount of marine grade sealant around the base of the cables, tubes and bolts and work around the areas with your finder until they are well covered.

Allow to cure.

15 Fitting the LED grommet

Drill a 4.5mm hole into the body as pictured.

Fit the supplied clear grommet through the hole.

Take the supplied 1” strip of velcro and cut to shape to fit over the LED stand off and put to one side (this will be fitted later).

Using a 2 part epoxy, apply liberally to the face and inside the hole of the LED stand off.

Fit the stand off over the grommet on the inside of the body and allow to cure.

16 Glueing internal parts

There are several parts that need to be bonded to the inside of the body – these should all be done using 2 part epoxy.

Velcro strips for securing the batteries – we recommend securing these with epoxy – apply liberally to the underside of the Velcro and mount in place as pictured.

Distribution board stand off -liberally apply epoxy to the underside of the stand off and fit to the body as pictured – aligned roughly with the two stand offs.

Cable stays – These come with adhesive pads, however we prefer to bond them in place using epoxy. To do this first remove the adhesive pads from the underside.

Bond a cable stay on either side of the body as pictured – these will be used to hold the breather cables in place. Once the epoxy has cured, use the supplied cable ties to hold the breather tubes in place.

LB2 Antenna mounts (optional)

The LB2 antenna mounts can be easily modified and mounted inside the body. If you want to utilise these brackets, first cut them down as below.

Then bond into place using epoxy and allow to cure.

Cable stays for motor cables – We recommend bonding two cable stays at the rear of the body so you can utilise them to keep the excess motor cables in place once the ESCs have been installed.

Fitting the gimbal mount

You will need to have purchased the Matrice 600 Series – Zenmuse X3/X5/XT/Z3 Series Gimbal Mounting Bracket

Take the following parts from the package (the rest can be discarded and are not used).

The rubber cable grommet is fitted to the electrics tray.

Insert the 4 rubber grommets into the mount on the inside of the body.

Remove the 4 screws from the gimbal mount tray and discard the tray.

Mount the gimbal mount to the HexH2O gimbal mount tray using the same 4 screws.

Cut the power cable down by 3” and connect a MT30 (this will connect to the power distribution board.

Plug the 2 supplied cables into the gimbal mount and put to one side.

Electronics Tray

Carefully slide the N3 flight controller into the mount as show.

IMPORTANT ensure the N3 is mounted upside down and using the correct orientation as per the picture above.

Slide the PMU into place as pictured.

Plug the PMU into the N3 as shown.

Tip: Support the N3 and N3 mount when pushing the plugs in as they can be stiff.

Fit the fan to the electrics tray as pictured and pass the power cables through the hold in the board.

Fit a MT30 connector to the end of the cable (this will later plugin to the distribution board).

Fit velcro to the N3 LED module (this will later be attached to the LED stand off) and connect to the N3 flight controller.

Take the pictured cable from the N3 wiring box and connect to the N3 flight controller and pass the remainder of the cable through the hole in the board (this will connect to the LB2 unit).

Using the 3M tape supplied with the N3 flight controller, cut strips and apply to the face of the LB2 unit as pictured.

Fix the LB2 unit to the electrics tray ensuring that the fan lines up with the hold in the board as pictured.

Connect the cable to the LB2 unit and tidy the cable using a ‘cable stay’ and cable tie as pictured. 

Fitting the wiring loom

Screw the distributer board to the stand off, being careful not to over tighten.

Then fit the cap onto the distribution board.

Mounting the ESCs

Apply a liberal amount of marine grade sealant around the base of the heat sink.

Pass the heat sink through the hole in the body and seat firmly in place – this creates a water tight seal from the inside.

You can wipe any excess sealant if preferred.

Leave the machine upside down and allow to cure overnight.

Connecting the MT60 connectors to the motor cables

At this stage the three motors cables can be soldered to the MT60 connector in any order. When you come to bench test the drone you will check the motor rotation – if a motor rotates in the wrong direction, you will need to swap the + and – connections on the MT60 connectors (which will change the motor direction). Each motor must rotate in the correct direction as per the diagram in the N3 assistant software.

Fitting the Electrics Tray

Label each ESC cable connector, making note of each motor from one through to six as per the diagram below. 

Pass the ESC cables through the electronics tray.

Connect the XT60 power cable to the wiring loom.

Connect the fan power cable to the wiring loom.

Connect the LB3 cable from the X3 camera mount to the LB2 gimbal port.

Slide the antennas into the antenna mounts.

Connect the GPS cable to the PMU module, and in tern connect the LB2 cable to the port on the GPS cable and fix to the electrics tray using 3M tape.

Connect the ESC cables to the flight controller (ensure they are in the correct order).

Ensure all cables are tidy and that none are trapped.

Ensure there are no cables obstructing the LB2 unit and carefully lower the electrics tray into place, ensuring the tray is aligned with the rear mounting brackets. Do not force the tray into position. If it does not easily fit in position then you have cables obstructing the LB2 unit that need to be moved.

Screw down the electrics tray using the screws provided.


Electrical components

The N3 flight controller must be configured to our default settings before use. These configuration settings can be found here: N3 Configuration Settings

Before you can use the X3 camera, it must be flashed with the DJI OSMO firmware. Instructions on how to do this can be found here: Installing OSMO Firmware to X3 camera

You drone is then ready to be bench tested.

For all other components used, please refer to the corresponding user manuals along with the HEXH2O PRO V2 User Manual which can be downloaded here:  User Manual Downloads