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Hot prime with DE (diatomaceous earth)


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Posted

Well the so called "Fencepost Prime" uses DE the reason for DE is that otherwise most of the heat that the prime develops goes away in the gasses, the DE stays in it's original place because it remains solid, it's this hot solid that passes the heat to the star. I don't have the formula but it is relatively well known.

 

The "hot slag" is also the reason why silicon is sometimes added to primes, Add silicon it burns to silicon dioxide which stays in place and passes it's heat to the star.

Posted

Well the so called "Fencepost Prime" uses DE the reason for DE is that otherwise most of the heat that the prime develops goes away in the gasses, the DE stays in it's original place because it remains solid, it's this hot solid that passes the heat to the star. I don't have the formula but it is relatively well known.

 

The "hot slag" is also the reason why silicon is sometimes added to primes, Add silicon it burns to silicon dioxide which stays in place and passes it's heat to the star.

 

you dont always have to use de,I dont,heres the prime of primes and I use wood meal like 80 mesh makes a nice rough star easy to light even mag/stars

PRIME

My Favorite Prime (Recent change from the Ti prime)

 

Name: Silicon Prime

Source: Dan Creagan (and others)

 

Reactive Charcoal (willow, pine, etc) ..... 15

KNO3 ...................................................... 75

Sulfur ........................................................10

Silicon .......................................................+10

SGRS (preferred) or Dextrin .....................+5

 

 

(you can also put it on with a 10% solution of Gum Arabic instead of water or water/alcohol)

 

Mix the first three ingredients thoroughly. Do not wet. All ingredients should be airfloat except the silicon. Additional benefit can be had by adding +10 diatomaceous earth or some 7F to get it 'bumpy' so it will take fire easily.

 

from cregans site

 

 

Posted

Hot prime with DE (diatomaceous earth)

 

http://en.wikipedia.org/wiki/Diatomaceous_earth

 

FLUX

 

Link below is about flux's of differing kinds.

 

http://pottery.about.com/od/diyglazes/tp/fluxes.htm

 

DE is primarily 80 to 90% silica, 2 to 4% alumina and 0.5 to 2% iron oxide.

 

Any opinions on what the best FLUX is to lower DE's melting temperature?

 

its only used to fluff the star the silicon is the heat source

 

Posted (edited)

Name: Fence-post prime

Source: Eugene Yurek

 

 

Potassium Nitrate 65

Charcoal Airfloat 12

Sulfur 10

Diatomaceous Earth 5

Silicon, 325 mesh 5

Charcoal, spruce, ball milled 3

Tare: Total: 100%

 

 

Below is a link about glass, with a lot of other links included about its properties.

http://en.wikipedia....Soda_lime_glass

 

DE = Diatoms as pictured below

gallery_10713_78_69121.jpg

 

These are single whole diatoms.

 

When you acquire DE powder it consists of whole & broken diatoms that look like a white fluffy abrasive feeling powder.

gallery_10713_78_150245.jpg

 

My question to any chemist out there, is there a pyrotechnic composition compatible FLUX that will lower the transition to molten temperature of DE?

 

 

Edited by oldguy
Posted

I was trying to come up with some ideas last night, but nothing was appearing too viable. The only thing I can really come up with that might be able to convert the DE or another SiO2 source into a liquid, or at least kind of sticky solid is sodium. Most direct routes would tend to use chemicals that cause other issues like NaOH or maybe Na2CO3. I wonder if perhaps NaHCO3 might be able to do the trick. Sodium silicate melts around 1090 C.

 

Through some more searching while screwing around today I got a better idea. Potassium salts tend to have lower melting points than sodium. On a very crude level this is observable in liquid vs. solid soaps. This however is not true for silicates at least, which is what I presume the "fluxed" species will be. The below document lists some data on potassium and sodium silicates. The pertinent information is on page 11. Sodium silicates tend to soften around 550-600C, where as potassium is around 700. Softening may be all that is needed.

 

http://www.inchem.org/documents/sids/sids/SolubleSilicates.pdf

 

I was trying to see if you could just increase the sulfur content to promote the formation of potassium or sodium sulfides, but I didn't get a lot of info if those would flux or attack silica.

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