Suggestions for Benzoate Fuel

[Czx7]

For my rockets I am currently running a 64/32/1/3 Kbenz fuel with iron oxide and mineral oil. I have seen many different formulas with some using wax instead of the oil with one being 72/28/1/3. Is it really just preference or is there a proven better formula? Also, is it just preference between mineral oil or wax?

[DavidF]

I like wax instead of Vaseline or mineral oil because it is solid at room temperature. I don't feel like it will soak into the tube, or act as a lubricant to help the grain 'slip' upon storage, which (I think) is the main cause for the change that results in CATO when whistle rockets are stored. Oil and grease are anti-binders, even though some refer to them as binders. One guy was using paraffin lamp oil as his phlegmatizer, and said he got quite an increase in power by using it. Turns out the stuff is somewhat volatile, and will completely evaporate if left out in the open. I declined to try it in whistle rockets.

The formula posted looks like it's for slow whistle with very little lifting power, unless a long spindle is used. 

[FrankRizzo]

I've always preferred red gum after reading Joe Domanico's whistle papers.

[Czx7]

With the wax can it be dispersed with acetone?

Also, with the whistle being slow I know copper oxychloride is hotter stuff but I don’t have any on hand. Is there a better formula for red iron oxide?

Edited December 29, 2024 by Czx7
Addition

[FrankRizzo]

No. Acetone is not a proper solvent for wax. You need a non-polar solvent like white gas (camp stove fuel), naptha, or xylene.

I like 76-23-1 (benz,perc,iron oxide) for rockets. I mill the red iron oxide into the perc (only these two together).

The mix you've been using at 64-32-1 is a slow mix from Steve Laduke (Whistle #3), used for his Long Winded Screamer rockets.

Edited December 30, 2024 by FrankRizzo

[Czx7]

Ok, thanks.