Monday, February 9, 2009
Arguments
Since I still view this as a technical thing, here's a bit of science I'd like to preserve.
How To Make Nitrous Oxide:
Take some ammonium nitrate and place it into a vessel capable of being sealed, with a tube coming out. Nitrous is formed around 170-240C, and above that it becomes a mono-propellant, which will cause the reaction to accelerate. You want to collect the gas underneath water, and allow it to float upwards into a container.
Saturday, October 20, 2007
Nitrocellulos Revisted - Hexanitrate
Power Labs left a nifty guild on how to make nitrocellulose, and here I'm writing some scaled calculations that may prove useful later.
For the initial ingredients:
98% Concentrated Sulphuric Acid (H2SO4)(l)
70% Concentrated Nitric Acid (HNO3)(aq)
Pure Cotton (90% Cellulose, (C6H10O5)(s)
Acetone (CH3COCH3)(l)
Sodium Bicarbonate (NaHCO3)(s)
Distilled Water
Diphenylamine (C12H11N)(s)
Now, to create the hexanitrate, Powerlabs indicates that you need 5ml acid mixture for every .5 g of cotton. So, for my purposes, 10ml Acid mixture will nitrate 1g of cotton. Hexanitrate uses 35% HNO3 / 65% H2SO4 (by volume) as the acid mixture.
To keep this simple, the acid + cotton mixture is:
1g Cotton
3.5ml HNO3 (98% Concentration)
6.5ml H2So4 (70% Concentration)
After the desired amount of Acid mixture and cotton is added, the solution must nitrate for 10 minutes never exceeding the temperature of 70o Celsius otherwise the solution will have 'a runaway nitration'. After the nitration, the cotton is washed in Sodium Bicarbonate, then in distilled water until the water used to wash is neutral. During the third wash, Diphenylamine should be added to get rid of the rest of the acidic content in the hexanitrate. When the water used to wash the Hexanitrate is neutral, take the hexanitrate and dissolve it in Acetone. After the acetone vaporizes, the Hexanitrate should be stored underneath water untill it is ready to be used.
20g Cotton
70ml HNO3 (98% Concentration)
130ml H2So4 (70% Concentration)
2ml Diphenylamine (C12H11N)
400ml Acetone (CH3COCH3)(l)
400ml Sodium Bicarbonate (NaHCO3)(s)
2 liters Distilled Water
Source: PowerLabs
Thursday, October 4, 2007
Saturday, September 29, 2007
Nitro Cellulose
So to create ncle
- Nitric and Sulfuric acid
- Nitrating agent (Both Nitric and Sulfuric Acids are Nitrators, so I don't know how that works out)
- Camphor, C10H16O. Available here if the chemistry department does not have it.
- Ethyl Alcohol possibly
- Zinc oxide or Zinc Carbonate
Quick Summary of the above link
- Starting material of cotton, ramie, flax, jute, or wood pulp
- Nitric and Sulfuric acid is added to starting material(cellulose)
- Nitrate the cellulose to 11%, then rinse with water
- Dry the ncle until there the water concentration is at 2% or less
- Knead the ncle like bread and then add a 50% solution of camphor in alcohol
- Add 1/15 as much Zinc oxide/Carbonate as ncle (It is mentioned that this must be added after the kneading. It is not mentioned whether or not this is necessary, so this could be dropped from the final formula.)
- Molding/pressing. Press the Ncle into a desired shape.
- Aging. The ncle has to be aged before fabrication, but since this will probably be molded from step 7, and also since the shape does not have to hold for a very long time in the rocket engine, it might not be necessary to age the ncle past an initial hardening.
Friday, September 28, 2007
Saturday, September 22, 2007
SEDS Hybrid

This is the basic fin design that Jeremy found. I think it will take some work for our hybrid rocket fins to look this seamless, especially since no one on the max altitude team has any experience with carbon fiber. Personally, I wish we could go ahead and get started with all this stuff, rather that have people sit and talk about what they think is the best design, or what they have done previously. Every rocket is different I think, and no amount of talking can replace experimentation. Also, we only have launch windows once a month, so if anything goes wrong it will take a month before we can truly verify that we have solved the problem. Overall, I'm not really satisfied with this project, I think that we should already be planning tests of the ping pong ball motor. The order I think is best for design would be to work on the motor first, get a 25:1 ration out of it, then to buy the electronics and parachute system, and then finally get the carbon fiber body and fit all those components into it. Right now there is no progress on anything, only discussions about rockets. Thats fine and all, but by meeting 4 something should start happening aside from simply 'forming groups'.
