Bottle Rocket B

[liger_98]

now, if u need the rules, check the website Soinc.org. All the rules are listed there. My question is how high should the fins be and what should the shape look like? plz no false answers seeing that i have done this event before (but failed) and i still kno what im talking about

[illusionist]

now, if u need the rules, check the website Soinc.org. All the rules are listed there. My question is how high should the fins be and what should the shape look like? plz no false answers seeing that i have done this event before (but failed) and i still kno what im talking about

Relax, no one here is going to give you false answers (although, there are a few trolls roaming around).
If you look at the post directly above yours, you'll find a link to the Image Gallery. Follow the link and check out some designs there. Also, if you simply google "bottle rocket fin" or something like that, you will get many websites and images that exhibit a wide array of designs possibilities. Don't expect a definite answer about what it should look like though.

[KKForever5]

Anybody have a good fin design? BTW I'm new here.

The Image Gallery has some pretty good shots of different fin designs that you might want to test. Look on different websites; there are also some designs that my partner and I found to be effective.

Thanks!

[technerd]

Does anyone know a good amount of fins, to put on the 1liter bottle??? Thanks!!

[fishman100]

Does anyone know a good amount of fins, to put on the 1liter bottle??? Thanks!!

3 will be enough to make a good backslider; 4 fins is unnecessary.

[jma]

Thanks Fleet 130 for your post.
I bought all the 1 litter bottles that I could find and they are all smaller than 2.2. My concern is that my rocket won't fit on the launcher provided on the competition day. However, I didn't see anyone mention anything about rockets/ launcher fitting problems. Therefore, I'll go ahead and fix my launcher to fit the 1 litter. Hopefully the comercial launcher from my regional will fit all the 1 litters as the ones you tested few years ago.

[fishman100]

now, if u need the rules, check the website Soinc.org. All the rules are listed there. My question is how high should the fins be and what should the shape look like? plz no false answers seeing that i have done this event before (but failed) and i still kno what im talking about

1)

The Image Gallery has some pretty good shots of different fin designs that you might want to test.

2) Google! There are a lot of interesting designs.

3) Make your fins out of basic shapes, such as squares, trapezoids, semicircles, etc. Everything helps, trust me!

4) How high the fins should be: Well I think it says in the rules that the distance between the front edge of the fins and the neck of the bottle is 5 CM, and you certainly don't want your fins to be protruding past the top of the pressure chamber, so try different sizes and shapes knowing these two parameters.

5) As illusionist said most people on the boards don't give "false answers" so you can rest assured that the responses posted are accurate!

[Lady Epidemic]

One thing that would help reduce drag on rockets is ,(it's easiest when you're using a trapezoid-like shape), is to make sure the leading edge of the side of the fin is slightly taller than the trailing edge, otherwise you get an extra side's worth of drag.

[Rocketeer]

I still have not figured out where the rules are posted on the soinc site. Am I just not clicking the right place? After the effect of the near force 6-7 winds on the launch last year, the 1 liter bottle sounds appealing. Does anyone know how to get the rules for this year and how to build or modify the launch pad? It sounds like the pressure will be 60.

[illusionist]

You cannot simply get the rules online. You have to either purchase them from the soinc.org store, or ask your coach for the rules (he/she should've gotten them by now).