Water Tower Rocket (18mm version)

I build a water tower rocket based around a Nestle's Quick can designed to fly on a 24mm motor. I launched it on an Estes E12-4 and it flew, but being such a large wide rocket it didn't get high enough for the 4 second delay. While that rocket survived the crash and will fly again (probably on an Aerotech E30T-4), I wanted a version I could fly on motors more easily obtainable. So I designed this 18mm version that flies pretty well on a C6-3.

The 18mm version is the yellow and red one in the photos. The 13mm version (little silver one) can be found here: https://www.thingiverse.com/thing:6201368

While I was successful in my modifications to the 33mm inner tube version of this rocket to get the chute to deploy, I recommend making the 42mm inner tube version as there is just that much more space for chute packing. Either version works, however, so the parts are here for both.

To build this rocket you will need:

• 75mm BT20 (18mm) body tube for the motor. This needs to be long enough for the motor AND the 18mm section of the engine block to sit in.
• 100mm BT55 (33mm) body tube. Leave this long and cut it down once the water tower tank is assembles. The bottom of this tube should fit into the notches in the "base" part and extend to the top of the "top" part. If using the BT55 tube, print the parts with the "33" in the name as well as the un-numbered parts.
• 100mm BT60 (42mm) body tube (ALTERNATIVE TO BT55: RECOMMENDED). This should provide a little more room for a recovery system. If using a BT60 tube, print the parts with "42" in the name as well as the un-numbered parts.
• 80mm BT80 (66mm) body tube for the main tank body.
• Shock cord (I used Kevlar line)
• 12" or 15" parachute. There's limited space for a chute in this thing, which is why I had issues on my launches, but 12" should be sufficient.
• 4 300mm long 5mm (1/4") dowels. You can cut a longer dowels to length or buy them this length in packages from Hobby Lobby, like I did.

Note this rocket has a cross brace halfway down the legs. When I launched it I used a clamp to keep the alligator clips close to the launch rod so they wouldn't snag on this brace while the rocket was launching.

NOTE: I have no affiliation to Warner Brothers. My son said this rocket looked like the Warner Brothers water tower from the Animaniacs and I couldn't resist decorating some in kind. Warner Brothers, if your reading this please consider this an homage and don't sue me. No Wakko's, Jakko's or Dot's were injured in the launching of these rockets. Though I was seriously tempted to print some little versions to put on them.

I have five videos of the 4 prototypes I made of this rocket. If you only watch one, watch the starred one, as it was the best launch (chute worked) of the included design (two are earlier prototypes) using regular PLA as a print material.

UPDATE 9/5/2023: I made the shoulder on the nose cone shorter to give a little more space inside the rocket for the chute. I also switched my personal versions from using a thick fireproof felt pad as insulation to using a piece of nomex cloth that can fold around the chute. Hopefully this helps with chute deployment. If not, I have an alternative design using a 42mm inner tube as opposed to the 33mm one, which should provide more space. I've not built that version yet, however.

UPDATE 9/6/2023: Decided to publish the parts designed for the 42mm inner tube. I've not tested this version as of this note but have every reason to believe it will fly.

Prototype 1: https://www.youtube.com/watch?v=_1KKio7Tk_Y
Prototype 2: https://www.youtube.com/watch?v=B8K0g9tIiB8

• Prototype 3 (Best): https://www.youtube.com/watch?v=Dk7UxNfaqaY
  Prototype 4: https://www.youtube.com/watch?v=Dk7UxNfaqaY
  Prototype 3 on B motor (Not recommended): https://www.youtube.com/watch?v=Romo6cddQ-8

Prototype 5 (42mm inner tube), this is the RECOMMENDED design: https://www.youtube.com/watch?v=SPkKZ7eT9JY
Prototype 3 retest (chute failure): https://www.youtube.com/watch?v=4C4yht4EzbE
Prototype 4 retest (Success): https://www.youtube.com/watch?v=j4JOCeZQ3J4