Jump to content
APC Forum

Recommended Posts

Posted (edited)

1. Is it possible to make ejection charge with KNO3 and Sugar ?

2. I am making rocket out of paper , how can i prevent it from catching fire ?

Edited by pipiso
Posted (edited)

There is a lot of information on this forum about rolling paper tubes for rocket engines. Look around the rocket forum! Its full of very interesting information! I'll give you some starting information though. Make your nozzle and header for the rocket engine out of scoopable kitty litter. When compressed it will turn into a hard plug which you can even drill. The tube wont burn through when rolled and glued properly. As far as an ejection charge; You will have to make some black powder for that or some other composition. Rcandy (as sugar rocket fuel is called) won't make a good ejection charge (remember it's what is powering your rocket to begin with). More importantly, you will need to make a delay before your ejection charge goes off. This can be done by making a short layer of rcandy at the top of the engine with about 10% sodium bicarbonate (baking soda) added to the composition.

Edited by MadMat
Posted

Thank you !

I have one more question not that important but i want to know what am i doing .Why Rcandy wont make good ejection charge but BP and Crimson powder will ?

Posted (edited)

Rcandy is rather slow burning. It makes a great rocket fuel because it creates more of a "push" when it burns. To make an ejection charge, you want something that will burn much faster and create a "pop". One other thing, if you become disappointed with the thrust of your Rcandy (this is especially important if you are making an "end burner" rocket as opposed to a "core burner" rocket) you can add approximately 1/2% of red iron oxide to your rcandy mixture. This acts as a catalyst and will increase the burn speed of the Rcandy. If you don't know the difference between a core burner and an end burner, you can find out by looking through the rocketry forum!

Edited by MadMat
Posted

Rcandy is rather slow burning. It makes a great rocket fuel because it creates more of a "push" when it burns. To make an ejection charge, you want something that will burn much faster and create a "pop"

What about 90/10 KNO3 sugar ?

Posted (edited)

I could probably type out a couple pages of information about making rockets, but, if you are seriously interested in making rockets you will find that getting the information and experimenting with that information is more than half the fun of building rockets. I feel that you would be disappointed by the performance of an ejection charge made with a variation of rcandy, I'm not 100% certain it wouldn't work but I've never used it. If you want to try it out, experiment a little!

 

Actually, the 65/35 formula for making rcandy is a balanced chemical equation. The oxygen produced by the potassium nitrate is the correct amount for the amount of sugar. Adding more potassium nitrate will just result in an excess of oxygen that isn't consumed in the reaction. You COULD try adding a different, faster burning fuel to the mix with the increased nitrate. Hmm.... you might be better off just making some black powder for your ejection charge and wait until you are a bit more experienced before trying something like that.

Edited by MadMat
Posted

RCandy, as formulated, is about as fast as it gets for a binary mixture of KNO3 and sucrose. A different ratio will probably just slow things down, and make it burns less cleanly.

 

Granulated Rcandy may work as an ejection charge. You'll need to experiment with it however. The majority of folks use black powder, which is why it is the most commonly discussed and used charge. MadMat is right in that RCandy performs better when under pressure however. If you have some spare rocket bodies that you wouldn't mind damaging, it might at least be worth some ground tests if you have your mind set on it. Keep us posted.

×
×
  • Create New...