When you get your first kit with a piston, one of the first things you will ask is: 'how tight should the piston be?'. Well a piston should be as tight as a nose cone or airframe transition, and how tight is that?

You should be able to pick up your rocket from the nose cone, transition or piston (recovery harness) WITHOUT ANY PART SEPARATING. Now you might think that is a bit too tight, but it's not. If you build your kit right and have a good solid motor retention system, then only one of two things can happen:

1. The recovery device is deployed
2. The rocket explodes

There is a saying in some clubs: 'Blow it apart or blow it up'. The chances of blowing the rocket up are pretty slim unless you've glued the parts in place...and you didn't do that did you? So, make sure that you can indeed pick up your rocket from the nose cone, transition or recovery harness without any part separating. The reason for this is to reduce the risk of something called 'drag separation' which occurs when one part of the airframe slows down much faster than another part of the airframe thus separating the rocket and causing premature deployment (which can cause serious damage to the rocket). Drag separation is unlikely in a low or mid power rocket, but it's best to get into the habit of making sure this can never occur in the first place.