the next type of fins are my favourite as they are very easy to make and put on and are the ones that i find most stable for the moment. the only problem is that when they crash at high speeds, these types of fins get destroyed very easily, bu fortunately, there easy to repare.
Circular Fins:
this type of stabiliser is a round piece of plastic taken from the flat, round bit of a bottle. it is attached to the main body of the rocket by rods, mine are bamboo skewers, they are easy to get (100 for around 2 euros) and are quite resistant, athough the best ones for bigger rockets are longer, bigger carbon fiber sticks, like the ones used to make the modern arrows. the further away you put the round bit from the main rocket, the more stable the rocket will be, but, this might call for a laucher re-design as the nozzle is further away from the ground with long fins... you can stick the rods with glue, but my favourit way is to use strong tape, but make sure if you are using tape to avoid gaps between the tape and the plastic as quite a lot of water goes there and will make the tape useless.
This system makes the center of pressure lower than with flat fins and also makes your rocket look very stylish
These kind of fins however, are not suitable for the top stages of a multi-stage rocket.
here are some pictures and diagrams(sorry bou the diagrams there made on paint in two sec
![Mr. Green :mrgreen:](./images/smilies/icon_mrgreen.gif)
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