Attachment of parachute to shockcord

On my LPR builds I just stuck the bottom of the chute lines through the eyelet on the NC and
pulled the chute through the loops. This always made the lines running up to the chute look tangled and concerned me but work fine for the project.

my current build, a pro series II kit, as a nicer chute and I was wondering if anyone has a way of attaching the chute lines to the a swivel that yields organized chute lines?

Absolutely. Swivels are a godsend. Since I started using them, I have never had to untangle a chute.

What I do, more for convenience than anything, is attach the shroud lines to a Quick-link, attach that to a swivel, and attach the swivel to the NC via another quick-link. Adds a little weight, but at least it's at the forward part of the rocket, so it adds a little stability, too.

Lots of vendors sell swivels.

https://cart.amwprox.com/index.php?option=com_virtuemart&view=category&virtuemart_category_id=29

https://onebadhawk.com/stainless-steel-swivels.html

https://rocketrywarehouse.com/advan...Csid=49123e6b652b447bc776ed1563f47251&x=0&y=0

I have all the hardware in hand. My question is attaching the shroud lines to the quick link. Is there any special method to keep all the lines organized rather than criss crossing?

Ah, sorry. I either just loop my lines onto the link freestyle, or else I tie them off, leaving a loop about an inch long.

It's fine, the more knowledge the better! Thank you for your input. It sounds like the lines are lightheartedly attached, I'll try to worry less.

I used to use swivels and quick links, but now the only place I use swivels is on the fin can of DD HPR rockets. All the motor eject MPR and HPR just have the chutes attached directly to the shock cord. No quick links, swivels, etc. Just put a loop of shock cord through the shroud lines and loop over the chute, then pull tight. Much less weight and works just as well. My observation is that as long that the nose cone can't swing back and pass between the shroud lines, they won't tangle. The shroud lines and shock cords also don't twist up when using motor ejections since everything spins at the same rate. I have found that putting the chute on the end of the cord and the nose cone about a third of the way down tends to work better.

That's been my experience, YMMV

Interesting, I had been putting swivels directly on parachutes and remain unimpressed with their job. Maybe the placement is at fault, or maybe I have crummy swivels.

Vethen said:

I have all the hardware in hand. My question is attaching the shroud lines to the quick link. Is there any special method to keep all the lines organized rather than criss crossing?

Click to expand...

Yes! There is but you have to ignore the kit chute assembly instructions. Shroud lines must be attached across the chute not to adjacent corners. see the attached picture below. Doesn't matter how many shrouds lines are used 3,6 or 8pieces (6,12 or 16 shrouds) they are all attached directly across the chute canopy. Yes all the shroud lines are the same length.

Attaching the Chute to the Shockcord can be done with a butterfly knot placed about 1/3 the distance between the NC and body of the model.



View attachment 6-Shroud line (12 attachment points)-b1c_12-03-09.pdf

View attachment 8-Shroud line(16 attachment points)-c1b_12-03-09.pdf

watermelonman said:

Interesting, I had been putting swivels directly on parachutes and remain unimpressed with their job. Maybe the placement is at fault, or maybe I have crummy swivels.

Click to expand...

I use the snap swivels on plastic LPR chutes because they are a convenient way to attach and remove the chutes, not because of what the swivels do. I use swivels to prevent shock cords from twisting up excessively. That is usually caused by the fin can spinning a lot as the rocket drops. I've found the swivels are most effective when attached to the fin cans since they are the source of the spinning. Any spinning and twisting of the chute and the rocket doesn't usually result in extensive twisting of the shock cord. There are exceptions of course.

Micromeister said:

Yes! There is but you have to ignore the kit chute assembly instructions. Shroud lines must be attached across the chute not to adjacent corners. see the attached picture below. Doesn't matter how many shrouds lines are used 3,6 or 8pieces (6,12 or 16 shrouds) they are all attached directly across the chute canopy. Yes all the shroud lines are the same length.

Attaching the Chute to the Shockcord can be done with a butterfly knot placed about 1/3 the distance between the NC and body of the model.

Click to expand...

Wow! That is the first time outside of my caving circles that I have heard anyone reference the " butterfly knot". I use them all the time during underground exploration for re-belays and tie ins. Great linear strength and a great knot for chute attachment.

Wow! That is the first time outside of my caving circles that I have heard anyone reference the " butterfly knot". I use them all the time during underground exploration for re-belays and tie ins. Great linear strength and a great knot for chute attachment.

Click to expand...

I learned the knot from sailing (called a linesman's loop there). It is my second or third most used knot for anything after a bowline. In addition to rocketry uses, it's a great way to get mechanical advantage on something you're pulling tight. Lead the line around the object you're pulling on, back through the loop, and pull. Instant 3:1 (less friction losses).