Kite Messenger

I have had a soft spot for kites since I've been a kid. I remember seeing these kite messengers or ferrys like this at kite festivals years ago. This is a kite messenger based on erwinha's Kite messenger 1.2. Big thanks to Erwin for helping me out with this project.

It sped up the line on it's first test and works great. Honestly, the hardest part of this project was sewing the sail. See in action here. This is still a work in progress, I will probably make more revisions as I get more flight time with this model.

Printing

Both messenger body parts (front and back) were printed with MakerGeek's PLA. Use rafts for the back piece. Went pretty heavy with the infill on these parts because they receive a lot of the punishment. 4 shells with 45% infill.

For all the pushrod, center spar holder and spring stop parts i chose to use NinjaTek's Semiflex filament. I love the way this stuff prints, it's strong and flexible. The outer piece of the center spar holder was printed in PLA. Their print grains are opposite one another to provide better strength (was not sure how much twisting and torquing this piece would receive under a load). 4 shells with 20% infill.

Materials and Assembly

Messenger Body
8mm OD carbon tube 5.75mm ID x 60cm length.
This must be a hollow tube in order to house the pushrod for the lock mechanism

Messenger Pushrod
1/8-in Brass Metal Round
Pushrod 67.65cm
Locking rod 39.5mm
These are rough measurements. The idea is to leave just enough play in the pushrod for the locking rod to clear the opening without leaving the back part of the lock.

Rollers
I chose to go with a cheap 1-in Dia Vinyl Sliding Screen Door Nylon Bottom Roller Assembly kit that I found at Lowes. Just gave it a bit of graphite to help reduce friction.

Center Spar Sleeve
Used short 7mm piece of 7/32" Round Brass Tube to sleeve the top sail spar with the center spar connector. Thought it would provide less friction than the ninjaflex would.

Sail and Spars
Used 4.75mm solid fiberglass round for both spars. I only bought a yard of ripstop nylon so my sail is roughly 36" wide and 36" tall. I trimmed the spars to length once the sail was complete.

Stop plates and Spring Stop
Cut up a wire clothes hanger to use as a line anchor to stop the messenger at either end of it's travels. the plate will take a counter sunk screw (Not sure of the size just used what i had lying around). I found a 3/4" x 3-1/2" compression spring at the hardware store to soften the messenger when it comes back down the line. The messenger spring stop should fit snug inside the spring after you feed it on the line.