24 replies to this topic

[Deano 1]

I use the Estes C comp, If you can't find it I'll dig it out for you, and I think my rockets are ok.

[dmeader]

I plan to start with a 75:15:10 mix jusy screened and take it from there, I have also found a few interesting effects to add when I get a consistant motor. Im sure I have seen the Estes formula but that was some years ago, would be great if you could send me it. Will save me hours of looking.

[dan100]

nice rocket, looks like im going to make some 1 pound tools soon then, just knocked up a spindle for 10mm id today, have to use whats at hand
thanks for the quick replies.

dan.

[Deano 1]

These numbers are rounded up or down for the nearest %.

Estes C

KNO3-----------72%
SULFUR-------13%
CHARCOAL---14% ( I use beech )
DEXTRIN------1%

I mill it all for half an hour and then pulverone it with around 5% water.

Hope this helps

Edited by Deano 1, 07 December 2011 - 10:03 PM.

[dr thrust]

I plan to start with a 75:15:10 mix jusy screened and take it from there, I have also found a few interesting effects to add when I get a consistent motor.I'mm sure I have seen the Estes formula but that was some years ago, would be great if you could send me it. Will save me hours of looking.

hello, the Estes formula is half the story dont forget to get a consistent motor they were hydraulically pressed.
i presume as this is your first foray into rocket motors you'll be ramming your propellant?
if so dont over look basic safety measures such as wearing face/ hand protection ie welders gauntlets, dont have your head over the rammer,dont have loose comp or open containers of comp near you, rocket manufacture was/is one of the most dangerous activites in pyro.

[Deano 1]

All my motors are pressed at 1200psi. I haven't tried hand ramming this comp, be careful, although it's only modified bp I would give myself a few extra seconds of fuse

[dmeader]

I will definetly try the Estes comp but will save it until I get some practice.dr thrust rest assured safety is always a top priority, best quoute I heard on these forums "Prepare for the worse, hope fro the best"I had considered pressing the comp.How would this be done. My thinking is either you could either press several times as if ramming, or slowly fill the tube gently tapping it to get rid of any air voids. Then press the entire charge once.

[Deano 1]

A press is a whole new project. When you press motors, you just press each increment instead of ramming

[starseeker]

A press is a whole new project. When you press motors, you just press each increment instead of ramming

Each increment = the i.d of the tube.

[Deano 1]

Thats right. It makes all your motors consistant.