Attach cute to bulkhead or shock cord?

[billdz]

Some kits call for the chute to be attached directly to the eye bolt on the nose cone bulkhead, while others say to attach it to the shock cord a few inches away from the bulkhead. Any thoughts on which way is better? I'd prefer to attach to the bulkhead with a swivel or quiklink - hard to attach one of those to a shock cord so it doesn't slide up and down the cord.

 

[smugglervt]

I generally tie a loop in the shock cord about a third of the way down from the nosecone and attach the chute there with a swivel and quicklink.

 

[samb]

To the shock cord: the Alpine Butterfly is your friend

https://www.animatedknots.com/alpinebutterfly/#ScrollPoint

[video=youtube;gX1dWKg6Ttc]https://www.youtube.com/watch?v=gX1dWKg6Ttc[/video]

 

[billdz]

Of course, why didn't I think of a knot or loop. What's the issue with tying to the bulkhead, more chance the chute gets twisted?

 

[AfterBurners]

I find it easier just to attach it to the shock cord.

 

[Banzai88]

There is no issue with it as long as your anchor point is secure. Some rockets recover better with the parachute attached in one point, some on the other. You'll have to fly it and see.

Usually, one experiments to get the straightest descent without helicoptering, which imparts horizontal/rotational velocity to the recovering airframe, and is famous for breaking off fins as the airframe rolls on first contact with the ground.

 

[mccordmw]

I have the parachute on a Quicklink that connects the shock cord and the nose cone.

 

[Nytrunner]

Like Banzai said, there doesn't have to be a problem attaching it to the bulkhead, if its strong enough.....

That being said, think about how the force flows in each of the setups.
-Attached to cord: The bulkhead attachment only experiences the shock due to weight of the nosecone.
-Attached to bulkhead of nose: The attachment on the bulkhead gets Double the shock of the whole system (1x from the chute pulling up, 1x from the weight of the booster/payload pulling down)

For that reason, I like to attach a short distance away from the nose with a tied loop.

 

[billdz]

Thanks for the replies, all makes sense, I'll attach to a knot on the cord