Recovery attachment hardware provides the critical interface between your parachutes and the rest of the rocket. Vehicles are often lost in rocketry due to broken recovery hardware.
A typical setup is as follows:
(PICTURE OF RISER, SWIVEL, QL, AND U-BOLT IN SEQUENCE, AND THE SAME W/ AN EYE BOLT + SAFETY WIRE)
Riser
A riser (skydiving term) is a piece of webbing that goes between the end of the parachute shroud lines and the rocket. It is usually tubular nylon or Kevlar. (Protip: REI 1” climbing rope for big rockets.) The ends can be sewn in a box w/ X pattern, or a water knot can be tied at the end. (See How to: Sew a Parachute for details.) Nomex shielding can also be done at the end of the riser if it is repeatedly being subjected to pyrotechnic charges.
(ALLLLL THE PICTURESSSS – specifically the ends of webbing.)
Swivel
The parachute can spin upon descent. If you are using an eye bolt, this spin can cause a torque strong enough to unscrew the bolt (see Odyssey, test flight 2). The swivel mitigates this issue by allowing the chute to spin without affecting the other attachment hardware as much. They are not absolutely critical to flight – but are highly recommended to prevent shroud lines from spinning around each other and unscrewing your eye bolt.
Quicklink
The quicklink attaches the swivel (or end of parachute riser) to the eye/U-bolt. It should be rated to take the estimated shock load of the chute opening. These often end up being high-mass parts, but they are easy to obtain and implement.
Don’t forget to torque them down when assembling the rocket.
Eye bolt (+safety wire)
Eye bolts are attached in one spot to a bulkhead, centering ring, or other attachment to the airframe. They will unthread due to spin during descent! They must be either epoxied/Locktite-ed in place by locking the threads, or held by safety wire.
Safety wire is used to hold eye bolts (among other things) and prevent them from unthreading. A safety wire tool should be used to twist the safety wire. (Link to videos about implementing safety wire)
U-bolt
U-bolts can also be used to attach the chute assembly to the rest of the rocket. They do not require safety wire because they are attached in 2 places – but they typically require more space. If possible, they should also be locked in place on their bulkheads/attachment points.
Many of these parts can be found on McMaster-Carr or Apogee Components.