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Posted (edited)

I recently ordered some chemicals to make some red rubber stars according to the directions/kit on Skylighter. That kit/project has you slicing the stars with a screen. Can rubber stars could also be pumped? I've looked around for an answer but I can't seem to find one.

 

Another question that's just total curiosity, is it possible to make a rocket with star comp? Again, just curious but I was thinking about it the other day. I guess there isn't really any benefit in doing this but it would look cool with some small bottle rockets if it worked.

 

 

Thanks for any help!

Edited by pyro92
Posted

i would think pumping rubber stars to be a pita as the texture does not really compress too much and does not really need to,unless you have a big star plate the solvent may evapourate before you finish pumping them, cutting in anyway would be more suitable imho. pumping is more suited to dryer charcoal comps and aqueous binders

 

it is possible to make a rocket with star comps but there is not much or no literature on them and i doubt they have much lifting power, go-getters are basically small rockets that can be made with star comps ive only seen them coming from a shell but im sure they would look good from a mine or even launched in singles as the first stage of a cake.

 

dan.

Posted
Red rubber star comp in 5/8 go getters on a small skewer launch quite well....fired out of a 2-3" mortar also...
Posted

It seems like it depends on the kind of composition. I pumped Bleser Red Mg just a few days ago: here.

 

From my experience of trying to pump rubber stars before it seems that it's easier to pump them if they have a high metal content and as little parlon as possible. Some say that red gum makes them less sticky, but I'm not sure of that.

Posted

It seems like it depends on the kind of composition. I pumped Bleser Red Mg just a few days ago: here.

 

From my experience of trying to pump rubber stars before it seems that it's easier to pump them if they have a high metal content and as little parlon as possible. Some say that red gum makes them less sticky, but I'm not sure of that.

 

 

i think red gum makes them less sticky if it is a long way from drying[ only just wet], there's pumping properly with comps that are suited to it, and then theres cutting cylinders with a pump from nearly dry comp. different things. the parlon content makes them rubbery and less likely to compress when pumped.

 

dan.

Posted

High parlon is what MAKES them rubber stars. I believe pumping them can be done, but it's requires some experimentation. I know a few people who have done it, but there isn't a lot of first hand experience out there. You have to come to a balance of enough acetone to activate the Parlon, but not so much that it becomes too fluid to pump. Much more is known about pumping with alcohol or water bound stars. For what it's worth, those stars will behave similarly if you just add 5% dextrin and bind with water, though they will probably be a bit slower burning. Given the speed some of those compositions burn at, that is not always a bad thing. I could probably dig up the formulas that those compositions were originally based on as well if you'd like.

 

You can most certainly make rockets from star compositions. Go getters are one form. If you look up some of the colored "chuffer" rockets, they are another type. Depending on the formula, they can have quite a bit of power. I've witnessed 3/4" colored propellants that clearly out preform BP core burners made on the same tooling lifting 4" vs. 3" ball shells.

Posted

Like I said, I've just done it.

 

Shimizu's Red Star Brilliant is also pretty easy to pump. There the parlon content is higher, but the magnesium is high as well:

 

Potassium perchlorate 30

Strontium nitrate 20

Magnesium 30

Parlon 18

Lampblack or charcoal 2

Posted

If you're lacking in a suitable screen, you can still very easily cut parlon bound stars. Let the patty dry off a bit until you can cut it without the knife getting bound in comp and the stars ozzing back in to each other, and you can cut it up traditionally with a knife, or if you lift the now hardening sheet up off the deck, with scissors.

 

Why do you want to pump them? I've also successfully pumped Palon bound stars, but it's not going to be the easiest way.

 

The solvent drying out as you're working makes maintaining an ideal consistency rather difficult... perhaps unless you're in a place with freezing winters.

 

Adding Red Gum, even only 2% makes a considerable reduction in the stickeyness. So does adding a small amount of alcohol.

Posted
The "Plasma Torch" Fountain project on Skylighter is essentialy a red parlon star comp used as a gerb. The gerb burns pretty fierce, so I tried making some rockets from the same comp, but they all CATO'd. I don't doubt that with a little dialing in, you could have a good red tailed rocket. Although you might just end up reinventing the wheel with the red mg chuffer comps that are published.
Posted

The "Plasma Torch" Fountain project on Skylighter is essentialy a red parlon star comp used as a gerb. The gerb burns pretty fierce, so I tried making some rockets from the same comp, but they all CATO'd. I don't doubt that with a little dialing in, you could have a good red tailed rocket. Although you might just end up reinventing the wheel with the red mg chuffer comps that are published.

 

Ruby Red and Emerald Green kan both be used as fuels. I have simply used my BP coreburner tools to make rockets with them. The dimensions aren't really ideal, though. It's a bit hard for them to take off.

Posted

High parlon is what MAKES them rubber stars. I believe pumping them can be done, but it's requires some experimentation. I know a few people who have done it, but there isn't a lot of first hand experience out there. You have to come to a balance of enough acetone to activate the Parlon, but not so much that it becomes too fluid to pump. Much more is known about pumping with alcohol or water bound stars. For what it's worth, those stars will behave similarly if you just add 5% dextrin and bind with water, though they will probably be a bit slower burning. Given the speed some of those compositions burn at, that is not always a bad thing. I could probably dig up the formulas that those compositions were originally based on as well if you'd like.

 

You can most certainly make rockets from star compositions. Go getters are one form. If you look up some of the colored "chuffer" rockets, they are another type. Depending on the formula, they can have quite a bit of power. I've witnessed 3/4" colored propellants that clearly out preform BP core burners made on the same tooling lifting 4" vs. 3" ball shells.

 

If you could find those formulas, that would be great. I'd rather try one of those formulas than waste a bunch of comp.

 

 

If you're lacking in a suitable screen, you can still very easily cut parlon bound stars. Let the patty dry off a bit until you can cut it without the knife getting bound in comp and the stars ozzing back in to each other, and you can cut it up traditionally with a knife, or if you lift the now hardening sheet up off the deck, with scissors.

 

Why do you want to pump them? I've also successfully pumped Palon bound stars, but it's not going to be the easiest way.

 

The solvent drying out as you're working makes maintaining an ideal consistency rather difficult... perhaps unless you're in a place with freezing winters.

 

Adding Red Gum, even only 2% makes a considerable reduction in the stickeyness. So does adding a small amount of alcohol.

 

I don't have any objections to screen slicing them, I was just curious if they could be pumped. I still have to pick up a screen to slice them with.

 

 

Thanks for all the help so far guys. Maybe once I get more experienced I'll try my hand at making some star comp rockets. The go getter project on skylighter is what got me thinking about them.

Posted
Parlon and Acetone is a nice binder system but you use a LOT of acetone cleaning up star pumps. For acetone based comps i prefer to cut with a knife - it's easier to clean a good knife than a star pump and piston.
Posted

I first tried to roll them, but lots of composition was stuck in the bowl. Then I cut them, but that didn't feel really good either, because I couldn't get it homogenous; it was partly too dry partly too wet. Pumping is pretty easy, except for cleaning the pump.

 

I was into parlon stars for a while, but I'm abandoning them more and more: my blue and green stars don't need any metal fuel, so it's simply easier to bind with dextrin or SGRS. If I could make strontium chlorate stars as well and keep them dry, I would also abandon both parlon stars and metal fuels completely.

Posted

I to moved from parlon to PVC and red gum and switched from pumping to rolling much easier and the star count to time involved is a major plus. Aside from crossettes I have stopped using pumps.

The clorine inPvc is lower but by tweaking the mix u can get a nice color.

 

And alcohol is cheaper than acetone although water and Dex is cheaper yet the dry time sucks on water bound I only use them for glitters.

Posted

The "Plasma Torch" Fountain project on Skylighter is essentialy a red parlon star comp used as a gerb. The gerb burns pretty fierce, so I tried making some rockets from the same comp, but they all CATO'd. I don't doubt that with a little dialing in, you could have a good red tailed rocket. Although you might just end up reinventing the wheel with the red mg chuffer comps that are published.

 

I like to use this as delay in my rockets but you can't add too much as it burns slow and will come to the ground still burning.

Posted
I pumped some comets using the rubber star formulas. I found that adding a little dry comp before filling with the wet comp made things a lot less sticky..... I would suggest trying small batches if you are going to try it.
Posted

After checking with Ned's recommendations..... no acetone.

 

Use denatured alcohol, which will use the redgum or resin as the binder.

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