Packing a 15" parachute into a BT50

[neil_w]

I have an annoying habit of designing and building medium-sized LPR rockets (in the 4-6 oz range) with BT50 core tubes. For rockets of this weight I typically use a 15" parachute. Often this is a plastic chute, but I recently bought a bunch of thin-mil chutes with the intention of replacing all my plastic parachutes.

These BT50s have me flummoxed. I can get a plastic chute jammed in there cleanly enough, but getting a nylon thin-mil chute in there is proving problematic, until I really packet it *tight*, which I'd prefer not to do.

What is a good strategy for packing a parachute into a narrow tube?

 

[techrat]

I'm scratching my head trying to figure out how to make a rocket from a BT-50 tube that weighs 170 grams. I've got many BT-55 based rockets and some BT-60 rockets, and I fly all of them on 12" chutes as they generally come in at about 140 grams or less (dry weight). Not sure where you are flying from, but if I flew on a 15" (unless I cut a nice sized hole), I'd be chasing my rocket for more than 1/2 a mile. And I gotta keep an eye on the rocket while also being careful where I step as the park we fly from is covered in deer poop (And so far, lucky I haven't had a rocket land in deer poop)... But that's the subject for a different post.

 

[neil_w]

I'm scratching my head trying to figure out how to make a rocket from a BT-50 tube that weighs 170 grams.

Just surround the inner tube with lots of design crap and it's easy.

 

[mh9162013]

Are you having trouble with the nylon parachute b/c of the thickness of the shroud lines and where they connect to the parachute? If so, this approach might help:



The link is set up where the video will start playing at the pertinent part of the video.

 

[lakeroadster]

Are you having trouble with the nylon parachute b/c of the thickness of the shroud lines and where they connect to the parachute? If so, this approach might help:



The link is set up where the video will start playing at the pertinent part of the video.

Genius! Thanks for sharing.​

I have an annoying habit of designing and building medium-sized LPR rockets (in the 4-6 oz range) with BT50 core tubes. For rockets of this weight I typically use a 15" parachute. Often this is a plastic chute, but I recently bought a bunch of thin-mil chutes with the intention of replacing all my plastic parachutes.

These BT50s have me flummoxed. I can get a plastic chute jammed in there cleanly enough, but getting a nylon thin-mil chute in there is proving problematic, until I really packet it *tight*, which I'd prefer not to do.

What is a good strategy for packing a parachute into a narrow tube?

It seems for some of my designs it's the combination of diameter and the available body tube length is what gets me in trouble. It would be great if the chute builders would list "min. packed dia. x length" for their various parachutes.​

​

I wanted to use 18" nylon chutes in my F-79, but ended up having to stay with plastic chutes, but upgraded to the "over the top" style parachute chords.​

​

​

​

 

[neil_w]

Are you having trouble with the nylon parachute b/c of the thickness of the shroud lines and where they connect to the parachute? If so, this approach might help:



The link is set up where the video will start playing at the pertinent part of the video.

That’s a great video, definitely some techniques I haven’t seen. Need to watch it about five more times to fully absorb the way he’s doing the folding.