18 replies to this topic

[Alan Fox]

Im interested in any work anyone else has done with nozzless rocket motors. Especially BP motors in the one pound range( 3/4 ID by 7 or 8 inch length). My desire here is to produce a motor quickly and easily for pyro use. Namely lifting a 2 to 3 inch shell to a safe height. I also plan to add TI to my fuel for a nice sparking tail effect. And before anyone says it Yes I know I could go the normal nozzled BP rought ,been there done that and now want to try something new and different. Any thoughts or experence?

[dfk]

This sight could probably tell you more on the subject than all the people in this forum together. Not that no one has the knowledge but probably more likely not the time.

http://www.angelfire...kets/index.html

As far as this guys concerned he invented the things. He's got specs for the tooling, the recipe for the comp he used plus some pictures and videos.

He recently added a section on a blue strobe comp for rockets that he developed that uses sugar as its primary fuel and CuO for color.

check it out.

Marcus

[alany]

Check out DJ's hidden page too, it has some amusing as well as interesting videos.

Telling you where to find the link to it would take the fun out of it.

[Phoenix]

I bet his ears rang for a while after THAT. (You'll know what I mean when you look at the page). Nice shell videos too.

Edited by Phoenix, 13 March 2004 - 06:10 PM.

[Alan Fox]

Ive seen the guys site on anglefire and he is the one that got me started on this kick. His using WD-40 to slow down the fuel and make a good hard grain is a great working idea Ive tried it and it works super. I did hope to find others who are expermenting with it with the hope of speeding up my learning curve. And keeping the large booms from coming from the area of my yard down to a mininum.

[alany]

Nosing is your friend with non-whistle nozzleless motors.

[Alan Fox]

Wow just when I thought I knew almost everything.......what is "Nosing"? I did a search and found it not.

[dfk]

I have used this method, incorporating 10w-40 motor oil when I was first starting out.
I used this in buzz b**bs, oil SLOWS so if anything it will prevent your rocket from CATO not the opposite.

So oil does work for slowing a comp but why not just use extra charcoal, you get the desired slower comp with an added charcoal tail.
You can't loose

Marcus

[alany]

Nosing in this context is a wrap of paper around the device tubing which extends beyond the end of the case. The fuse or other matching goes through the nozzle as normal, then the paper is drawn around the fuse and tied in place with some string, usually tied off with a clove hitch.

A drawing would explain it better.

[Mortartube]

The "nosing" Alany mentions is also known as a capping. Like on gerbs.

[dfk]

So oil does work for slowing a comp but why not just use extra charcoal, you get the desired slower comp with an added charcoal tail.
You can't loose

I take that back.

While thinking about it today I realized the oil serves a more important purpose than I origionaly gave credit for. Being that it is nozzless, the oil serves to better hold the BP grain intact since the nozzle is not there to do it.

sorry for the mess up, I guess you'll just have to make do without the tail.

Marcus

[paul]

Hello!

I work with nozzleless rocket motors for pyrotechnic effects. They use potassium nitrate and sorbitol as the propellant. It is poured in when still hot and soft. Then a 8mm stainless steel rod is inserted.... For pics have a look on this:

http://deutsch.250x....m/raks_25mm.htm

These rockets are quite powerful

The rockets casing is produced like this:

http://deutsch.250x....m/doit/doit.htm



Sorry if it doesn?t fit in here, cause its no blackpowder rocket motor. But I think its worth a look, because these rockets are powerfull and less labourous as blackpowder rockets! Also very cheap...

[alany]

I take that back.

While thinking about it today I realized the oil serves a more important purpose than I origionaly gave credit for. Being that it is nozzless, the oil serves to better hold the BP grain intact since the nozzle is not there to do it.

sorry for the mess up, I guess you'll just have to make do without the tail.

Marcus

Yeah the petroleum jelly in whistle does the same, makes the grain much less likely to chip or crack if abused and makes it easier to press. Both are mainly used a phlegmatizer though, the other benifical side effects are just a bonus.

[Alan Fox]

Just got back to working with these lately and have come up with a reliable motor. Im building a one pound motor/ 3/4inch by 6inch. at the "nozzle" end I use normal core burner tooling and the first scoop is BP with 5% oil added it makes a nice clean and hard end to the motor then ram as normal with your standard 70 15 10 B P mix that is ball milled for several hours. I ram until to the top of the core then switch to a very slow mix propellent to the top of the motor sealing with a normal clay plug. The motors are very loud and fly especially fast. IF you use a coarse charcoal in the slow mix part of the motor you get a interesting tail that shows up after most of the noise has departed. I often top them off with nice BP willow stars, it makes for a great rocket that is quick to put together.

[chim-chim]

Paul mentioned Sorbitol, which was interesting because I hadn't thought of a sugar based nozzless rocket. Alany mentions whistle. This got me thinking, whistles are coreless. Does anyone know of any other compositions that could be used for end-burning. I wouldn't want the rocket to whistle, and have no benzonate and no press. We all know not to ram whistle mix. If it can't be poured to set or rammed, the advantage of ease slips away.

Probably a pipe dream but,

fuel...ram...fuel...ram...fuse...stick...done,

I had to ask.



P.S.- Hi everybody, newly registered long time Guest here.
Old (33), Long-haired (center-back), Geek (software trainer) Yank(California). Thanks all for the great info and ideas.