Fake Rocket Motor - Aka Building the Hawk-1F Module for My Rocket Drone

Hi there and welcome to my 'ible' #44.

This project can be considered an extension of 2 of my previous ones...

https://www.instructables.com/id/Landing-a-Rocket-...

https://www.instructables.com/id/Mini-Fog-Machine-...

As you can see, I've previously built the mini fog machine for my Hawk-V (I will attempt to land vertically), to simulate the condensation of Liquid Oxygen, before the launch of the rocket.

When I've finished to build it, I've realized that - with a bit of ingenuity - I could also use it as a fake motor for my Rocket Drone, simply buiding another module. (Currently I can launch it using pyro and water rockets)

Please take a look at the link listed above.

Supplies

1x Mini Motor Air Pump Pressure Oxygen Pump DIY Aquarium Fish Tank https://ebay.to/2GOv7dD
1x MT3 EVOD Colour Atomiser E-Cig Vape Pen Free Coil Replacement Clearomizer 2ml https://ebay.to/38YNrNb

1x DC Wireless RF Switch 433Mhz RC Relay Switch, 1-Channel https://amzn.to/36QrQVG

2x A4 Correx sheets 5mm

8mm ID x 11mm OD Clear Flexible PVC Water Pipe Hose https://amzn.to/2uTFf2i

1x Aquarium Plastic Hose Pipe Tube Connector Joiner https://ebay.to/2GO2hKI

Soldering on iron (please use it if you have the appropriate age)

Hot glue gun (please use it if you have the appropriate age)

UHU Glue

1x cardboard cylinder 3cm diameter (I've used the one for the organic waste bags)

1x short plastic hose (soap dispenser)

1x 1.5L bottle water (body)

1x 500ml bottle water (nozzle)

Electric wire 1 meter
Glycerine 50ml

Distilled water (not de-ionized) 50ml

A drill with 3mm drill bit (for metal)

1x Bamboo Skewer

Acrylic painting (white and bronze)

White electrical tape

2x LED (blue, or yellow)

Step 1: Building the Interchangeable Module With the Nozzle

As I've previously done with my Rocket Drone project, I've built different modules that allow me to launch the Rocket Drone using pyro and water rockets.

I thought it would have been very cool to build a fake rocket engine, activated remotely, that basically just makes a lot of smoke when I want to.

Using a cardboard cylinder (which is 3cm of diameter), and the same building process previously used for my Rocket Drone, I glued the "motor mount" inside a bottle of Saka water (I've built a lot of water rockets with it).

Regarding the fins, I have designed a template (used for all my rocket modules).

Once you've cut the fins, glue them to the body of the rocket, checking that the second stage is perfectly straight when the fins touch the ground.

Using an upper part of a water bottle, I've made a nozzle that hides the cardboard cylinder (which keeps the fake motor in place).

I've painted bronze, because I wasn't able to find the silver colour. :-)

Step 2: Wiring the E-cigarette and Assembling the Fake Motor

This is the most tedious part of the building process.
You have to drill a hole, to slide inside the base of the atomiser the electric wires. After that, solder the black cable to the external part of the atomiser and the white one, to the central part/positive (being sure you are not covering the hole with the tin).

Solder the wires to the motor of the electric pump.

Make 2 small cuts at the base of the small pipe, that will avoid the electric wires get squashed/damaged.
Using the glue gun, glue the small pipe, being sure it makes a good seal.

Attach the pump, using a lot of hot glue, creating a strong bond without having any leak.

After that, you have to build a T connector.

To complete this task, I've cut 3cm out the PVC hose, making a hole that fits the mouthpiece of the E-cigarette and glueing to it.

I've cut the plastic elbow as shorter as possible, creating an U shape, that prevents the hose to be completely folded, blocking the exit of the smoke.

Of course, I've closed the other part of the T, using a small piece of plastic, that I glue into it.

The overall weight of the fake rocket motor should be below 50 grams, regarding its length, it should be the same of the cardboard cylinder, you are going to use as a support.

Do not power the E-cigarette without putting the liquid inside the tank, otherwise you'll burn the resistance coil.

Step 3: Wiring the Remote Control

The idea was to activate the fake rocket motor remotely, therefore I had to buy a 1 channel relay, controlled by a remote control.

I actually could have done that, using the switch for the light of the MJX X101 drone, but I've burnt it, because I've connect to it to the motor of the pump, and the switch wasn't able to sustain the amount of current drawn by the motor itself (0.5A).

Hence, I've decided to extend 2 electric wires from the battery (used for the strobe light of my Rocket Drone), keeping the circuit for the activation of the fake rocket motor, separated from the receiver of the quadcopter.

In this way, I can replace the "fuel" for the E-cigarette, simply sliding the motor out the cardboard cylinder.

As you can see I've added 2 LEDs to simulate the combustion. I must say that to do a better job, the LEDs should have been yellow.

Please be aware that the liquid will last for no more that 3 minutes. If you don't add other liquid, you'll burn the coil resistance of the E-cigarette.

Step 4: Test It!

I've watched a lot of YouTube videos, but I came to the conclusion that the best liquid is made 50% with Glycerine and 50% by distilled water (not de-ionized). Outdoor use

Put 50ml of Glycerine and 50ml of distilled water in a jar, with a top. Shake it a lot, to making the fluid smooth.

After this task, put it inside the E-cigarette tank.

If you want to skip this step, you can also buy the specific liquid, but please be aware it contains nicotine.

By the way, this fake motor and the fog machine have been made for an outdoor use only.

Step 5: Attaching the F Module to the Main Stage

I really like modular things, because I can assemble them in seconds.

Basically the only thing to do is to attach the battery connector, to the main stage.

I use the same water bottles to build all the modules shown in the picture, therefore switching them is a matter of seconds.

When I've built the Rocket Drone, I placed in it a 3.7V Lipo battery for the strobe light, therefore this circuit is separated from the main receiver of the quadcopter (MJX X101).

The module has a tight fit, but the 1F module is heavier (164 grams), therefore I secured it to the main stage, using some white electrical tape.

The fake rocket motor can be slided inside the cardboard cylinder and (if you have taken the right measurements), the T connector should guarantee a tight fit.

To keep the nozzle of the fake rocket motor in place, I've used a piece of foam for packaging I've cut rounded.

As you can see I've added 2 LEDs to simulate the combustion. I must say that to do a better job, the LEDs should have been yellow.