The difference ballast makes
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The difference ballast makes
Does having the proper ballast improve rocket performance? Yes, yes it does.
Same 2 liter rocket at 100psi, 1st launch with less ballast, 2nd with more.
Same 2 liter rocket at 100psi, 1st launch with less ballast, 2nd with more.
Bugwubber
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Re: The difference ballast makes
Wow twice the height! I can see how that would make a difference. Even just adding weight to a soda bottle without fins makes it go higher. What is your best speed for a 2 liter rocket. Mine is 74 mph. That isn't great but it still is fast!
Water Rocket Expert
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"Anyone who has never made a mistake has never tried anything new." -Albert Einstein
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Re: The difference ballast makes
Registered 176fps on another launch yesterday. So about 120mph.Water Rocket Expert wrote:Wow twice the height! I can see how that would make a difference. Even just adding weight to a soda bottle without fins makes it go higher. What is your best speed for a 2 liter rocket. Mine is 74 mph. That isn't great but it still is fast!
Bugwubber
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Re: The difference ballast makes
Where on the rocket did you put the ballast? I have never thought about adding weight.
It does make perfect sense. The extra weight has more kinetic energy which keeps the rocket going for a longer period of time. Why didn't I think of this before?!
It does make perfect sense. The extra weight has more kinetic energy which keeps the rocket going for a longer period of time. Why didn't I think of this before?!
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Re: The difference ballast makes
The most effective location is the nosecone. Back in my pyro days, I remember tying a string to the rocket and swirling it in the air to make sure it flew right. There was some kind of clay that came with the kit that could be smeared onto the inside of the plastic nosecones that would add weight so it balanced on the cg mark.DogLover wrote:Where on the rocket did you put the ballast? I have never thought about adding weight.
It does make perfect sense. The extra weight has more kinetic energy which keeps the rocket going for a longer period of time. Why didn't I think of this before?!
Keep in mind this is for a single bottle (short) rocket. A long rocket might not need any additional weight.
Bugwubber
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Re: The difference ballast makes
Weight is better for distance, but can be used for height. A big rock is going higher than a small rock if you throw it, but too big and it is going lower. You see.
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Re: The difference ballast makes
Ah, ok this makes sense. Thanks.bugwubber wrote:The most effective location is the nosecone. Back in my pyro days, I remember tying a string to the rocket and swirling it in the air to make sure it flew right. There was some kind of clay that came with the kit that could be smeared onto the inside of the plastic nosecones that would add weight so it balanced on the cg mark.
Keep in mind this is for a single bottle (short) rocket. A long rocket might not need any additional weight.
-Blenderite
Check out my YouTube channel: https://www.youtube.com/c/Blenderite
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Re: The difference ballast makes
If the rocks are made from the same material (same density) and both are thrown at the same speed, then the question ultimately comes down to which rock has a better aerodynamic shape. The idea of putting weight on a rocket is to increase the average density so that the rocket has more momentum than a less dense rocket but not so much mass that the top speed is reduced.Water Rocket Expert wrote:Weight is better for distance, but can be used for height. A big rock is going higher than a small rock if you throw it, but too big and it is going lower. You see.
The batter comparison is throwing a baseball vs. throwing a wiffle-ball.
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Re: The difference ballast makes
Yup, there is such a thing as 'optimal mass'. Lighter is better for speed but you often have to add mass to a rocket to optimize altitude.
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Re: The difference ballast makes
Thats great information you have collected their bugwubber. Many say to make rockets as light as possible and avoid the use of a recovery system as this adds weight- but from what you have shown, it looks as if a recovery system on top of the rocket could act as ballast, as well as recovering the rocket in style via a parachute!
Cheers, Jamie B.
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Jamie Bignell,
jamie.s.bignell@gmail.com
Somerset UK
"The important thing is to know how to take all things quietly" -Michael Faraday.