mtnmanak
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@JimJarvis50 I watched your video & I have a question. What exactly is a z-fold? I've Googled it but didn't find anything useful. Does anyone know of a video that explains how to do a z-fold?
It is a method of folding your shock cord, shroud lines, bridle, etc - anything that is a cord or strap - using a series of folds that fold back on themselves and form a series of "Z"s. This allows force to be applied to one end of the cord and it will deploy in an orderly manner. In the photos below, you can see a shock cord laid out in a loose series of "z-folds" then what it looks like when you push them all together neatly. Imagine the end with the blue heat shrink tubing attached to your nosecone, coupler, bridle, etc and the loop with the yellow heat shrink tape attached to a parachute. When the parachute pulls on the cord, it neatly unfolds towards the hardpoint attachment and doesn't tangle. This method also ensures you can pack the cord in the tube in the most efficient manner. For long cords, multiple z-folds along the cord are usually required. For packing a deployment bag, you must use this method. I am not aware of any other folding method to get the cords properly folded into the d-bag stays.
For a smaller rocket, you would probably not want to use a strong rubber band to hold the z-fold together - you may not want to use a rubber band at all just z-fold the cord and neatly place it in the tube. There needs to be enough weight to overcome the ability of the rubber band to hold the stack together. It all depends on what kind of rubber band you use. I have some very lightweight dental rubber bands that work great for lighter rockets.