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Melting KNSU propellant

Hi,

I was making my first motor some days ago and i was going to melt the 65/35 KNO3/Sugar propellant. I had the temperature in the oil bath between

190-200, mostly near 190. I started with a small quantity of propellant as was told on Richard Nakkas website(to start with small amount and when that is melted, add more). As also said on his website, i stirred the mixtures constantly. But the mixture didnt begin to melt, it just formed chewing-gum-like chunks which went slowly brown. When i didnt stirr the propellant, then the bottom part of it turned to brown. Then i just decided to make the propellant in small portions and cast those chunks. But what went wrong? Or are those chunks what i really need?

Best, Ronald

PS The casting process was a failure anyway, because i forgot to put grease on the dowel(from wood) i used to form the core and i didnt get the dowel out of the grain :))

Reply to
Ronald Tammepõld
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Ronald, Stop.

Go back to Nakka's site and re-read everything on KNSU. Then re-read it again. Finally, read it all over again.

You MUST be able to figure out what went wrong and why before you proceed. If you cannot discover your mistake, you should NOT be doing this. Properly made, a KNSU melt will be a smooth, very viscous, amber to light brown "batter" with no lumps at all.

DO NOT USE THE PROPELLANT YOU MADE FOR ANYTHING. USE A HOSE AND DISSOLVE IT INTO YOUR YARD AS FERTILIZER.

I cannot emphasize enough the importance of UNDERSTANDING what you are doing when making any propellant.

Please, go back and analyze your process in detail. Come back and tell us what you did wrong and why you got the reults you did. THEN ask for advice on how to it better.

Reply to
Gary

Ronald:

Your question would be better addressed in the ROL EX Forum. Lots of good people there to answer questions.

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Select "forums", then select "Amatuer/Experimental."

You may need to set up an account if you haven't already done so.

Good Luck.

-Boomer

Reply to
Boomer

Ronald,

I see 2 problems:

A. Not knowing the melting point of Sucrose (or sorbitol)

B. Not knowing exactly what your doing.

READ Nakka!! effects of over heating,

Then read about the propellant:

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I have fired KNO3 motors, and I had thought to put my method on the net, but I figured that links to Nakka and TTA would be MUCH better!

BTW: your melting at MUCH too low a temp. I'll let you figure that out. I know its a pain when people just don't tell you,. However the only way for you to truly learn is to find out your self. NOT BY TRIAL AND ERROR, but by research.

Let me know how it goes.

- Theo M.

Reply to
Theo McD.

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