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Extreme Air Mail! Mailing Tube Rocket Project!
- Thread starter Weldo
- Start date
- Joined
- Sep 7, 2019
- Messages
- 674
Got the chute cut out today. 30" round with 8 eyelets. The eyes are just holes punched and reinforced with plastic stick on rings.
Tomorrow I'll begin the tedium of doing the lines!
What do you guys think of spill holes in parachutes? I've read it can help the chute inflate more quickly and remain better inflated in the descent.
Tomorrow I'll begin the tedium of doing the lines!
What do you guys think of spill holes in parachutes? I've read it can help the chute inflate more quickly and remain better inflated in the descent.
- Joined
- Sep 7, 2019
- Messages
- 674
Got the chute made up today! Here's a pic of the line termination. I tried to keep it neat.
The line used is 30lb braided fishing line. It's super strong and doesn't have much if any memory. Not very flame resistant though...
I followed this method:
Except I had 8 lines. I brought each individual loop together and tied a small overhand loop in the end so I had 4 overhand loops at the end of each pair of shroud lines. I then put them carefully onto a small split ring and then onto a snap swivel.
I wrapped it all in masking tape to keep it neat.
I made each of the shroud lines 1.5 times the diameter, which for my 30" chute is 45". and since I was doubling the lines, getting two shroud lines per string, I doubled that as well so I used about 90" to make each pair of lines. But now I'm wondering if that's too long.
I seem to recall that the 1.5 times rule applied to the inflated diameter of the chute but how the heck are you supposed to know that?
Anyway, just dragging it around the shop it seems to inflate well and even.
The line used is 30lb braided fishing line. It's super strong and doesn't have much if any memory. Not very flame resistant though...
I followed this method:
Except I had 8 lines. I brought each individual loop together and tied a small overhand loop in the end so I had 4 overhand loops at the end of each pair of shroud lines. I then put them carefully onto a small split ring and then onto a snap swivel.
I wrapped it all in masking tape to keep it neat.
I made each of the shroud lines 1.5 times the diameter, which for my 30" chute is 45". and since I was doubling the lines, getting two shroud lines per string, I doubled that as well so I used about 90" to make each pair of lines. But now I'm wondering if that's too long.
I seem to recall that the 1.5 times rule applied to the inflated diameter of the chute but how the heck are you supposed to know that?
Anyway, just dragging it around the shop it seems to inflate well and even.
I remember as a kid having a 2 stage rocket. Lost the 1st stage so just fired the rocket single stage. Eventually ran out of single stage motors, so without thinking fired off the rocket with the 1st stage motor............................. My 'chute strings AND my chute wasn't very flame resistant. 
- Joined
- Sep 7, 2019
- Messages
- 674
That's correct, a first stage motor is usually called a booster and has no ejection charge so when it reaches the end of its burn the flame just shoots out of the top and burns up the chute. It's this flame that is supposed to ignite the upper stage.
I got mine back because I was in Kansas, miscalculate the non stop wind and your rocket will land 30 miles away. No matter, it's so flat there you can still see it 30 miles away, although the walk is a pain.