Cut Stars

[nater]

I made some cut C6 stars tonight, just a small batch to try it out. I need more practice, or a better eye on how damp the comp should be. It seemed like I could not get the comp to hold together. After adding 30% water + 10% alcohol, I thought I had the comp wet enough. I was able to get a pancake of comp to hold together, but many of the stars crumbled when I tried to cut them. What I have is drying now and I think I'll use the comp that fell apart as rocket delay.

 

I'm not giving up on cut stars, but I ordered a star pump. Hopefully I'll be able to get some good stars dried in time for a shoot in the middle of September. I was aiming for 1/4" stars for headers on 4oz rockets. Is it easier cutting larger stars? I cut a few rows larger, and those look like they're holding together good. Do larger batches work better?

[pyrokid]

I made some cut C6 stars tonight, just a small batch to try it out. I need more practice, or a better eye on how damp the comp should be. It seemed like I could not get the comp to hold together. After adding 30% water + 10% alcohol, I thought I had the comp wet enough. I was able to get a pancake of comp to hold together, but many of the stars crumbled when I tried to cut them. What I have is drying now and I think I'll use the comp that fell apart as rocket delay.

 

I'm not giving up on cut stars, but I ordered a star pump. Hopefully I'll be able to get some good stars dried in time for a shoot in the middle of September. I was aiming for 1/4" stars for headers on 4oz rockets. Is it easier cutting larger stars? I cut a few rows larger, and those look like they're holding together good. Do larger batches work better?

 

 

Hey nater,

 

 

From my limited experiences, you get far better at making cut stars as you practice. The wetting process grows easier, as does forming the stars themselves.

 

Good luck!

[Mumbles]

There are two different methods for cutting stars, which require different wetting levels. One method is designed for bigger batches where the composition is wet and pounded into a loaf of star composition in a box resembling a bread pan. From there you get it out, cut it into slices, and then dice them into star. The other, which is the one I tend to stick with, is to wet it further and roll in into a patty. I use two wooden dowels to serve as height guides, and a dowel or PVC pipe to roll it into a patty. From there you just slice and dice.

 

For the patty method I find the composition is just right when I can compact it into the bottom of the wetting bucket and cut it up into a few slices like you're cutting a cake or pie without it crumbling it's good to go.

[Algenco]

Nater,

 

What did you use as a binder? SGRS doesn't like alcohol.

I wet my charcoal comps ,press it in the bottom of the bucket/bowl, cover and let it set for 10-20 minutes, give the binder time to activate.

[nater]

I used homemade dextrin for the binder. I let the comp sit about 10 minutes after wetting. I did form the patty in the bottom of my bowl, I must have just needed a little more water. It seemed like quite a bit. This is why I only made 4 oz to start.

[PersonGuyDude]

I made some cut C6 stars tonight, just a small batch to try it out. I need more practice, or a better eye on how damp the comp should be. It seemed like I could not get the comp to hold together. After adding 30% water + 10% alcohol, I thought I had the comp wet enough. I was able to get a pancake of comp to hold together, but many of the stars crumbled when I tried to cut them. What I have is drying now and I think I'll use the comp that fell apart as rocket delay.

 

I'm not giving up on cut stars, but I ordered a star pump. Hopefully I'll be able to get some good stars dried in time for a shoot in the middle of September. I was aiming for 1/4" stars for headers on 4oz rockets. Is it easier cutting larger stars? I cut a few rows larger, and those look like they're holding together good. Do larger batches work better?

 

As Algenco mentioned, I find it helpful to get close to where I think the star is wet enough (~70% of the way by my perception), then I let it sit in a closed container for 10 minutes or so. This seems to let the water diffuse evenly throughout the comp and makes it easier to cut, especially with comps high in charcoal.

[allrocketspsl]

I made some cut C6 stars tonight, just a small batch to try it out. I need more practice, or a better eye on how damp the comp should be. It seemed like I could not get the comp to hold together. After adding 30% water + 10% alcohol, I thought I had the comp wet enough. I was able to get a pancake of comp to hold together, but many of the stars crumbled when I tried to cut them. What I have is drying now and I think I'll use the comp that fell apart as rocket delay.

 

I'm not giving up on cut stars, but I ordered a star pump. Hopefully I'll be able to get some good stars dried in time for a shoot in the middle of September. I was aiming for 1/4" stars for headers on 4oz rockets. Is it easier cutting larger stars? I cut a few rows larger, and those look like they're holding together good. Do larger batches work better?

 

I use to cut alot of stars and skylighter has great " how to projects" on their web site,one is a Ned G. one, where he says most over do it on wetting comps,so put on scale the comp your wetting and spray the percent using your scale,exp: comp in the container weighs 300 grams so spray 5% or 15 grams.That way you get it right instead of guessing the amount. If you pump stars it to me is alot easier and makes better size stars,simple plastic tube with a plunger,I have 1/4,3/8,1/2 inch plastic tubing and use dowels for plungers cheap and easy and you can compress the comp in the tube before pressing it out and cutting. C6 pumped stars are a breeze , like you said the edges crumble i dont care how you cut them. TIP: I pump my stars over a bowl of prime so when I cut the star it falls into the prime and once you get the hang of it you can pump and cut quickly with very consistent sizes and prime them at the same time then when done hand roll or put into your stars roller or into a bowl of color comp if your making color changing stars.

[nater]

I did weight exactly how much water I was putting on the comp. I made that mistake a while back when granulating rocket fuel. It quicly went from too dry to hold together to soupy mess and I was trying to avoid that with these stars.

 

I do like the simplicity of cutting them. Maybe I will make a frame to pack the comp in better before I slice them.

[Algenco]

I did weight exactly how much water I was putting on the comp. I made that mistake a while back when granulating rocket fuel. It quicly went from too dry to hold together to soupy mess and I was trying to avoid that with these stars.

 

I do like the simplicity of cutting them. Maybe I will make a frame to pack the comp in better before I slice them.

 

 

Dextrin will do that, too dry add a drop more and it turns to soup

 

Wheat paste is the best for charcoal comps

[moondogman]

Nater

Make some parlon rubber stars, they are much easier than the charcoal ones IMO.

Steve

[nater]

Nater

Make some parlon rubber stars, they are much easier than the charcoal ones IMO.

Steve

 

I'm planning on making some at Tri-State pending an order with Karl. I gotta have my blue stars mixed in with the charcoal streamers.

[Bonny]

When I make cut stars, it mix the comp in a ziploc bag. Add the required water, and knead it in. Mash it into a lump a few times and continue to work it. As others mentioned, wait for the binder to activate. I wait anywhere from 10-30 minutes (depending what else I am doing at the time). If the comp seems dry, I add some more water and knead again, but at that point I don't wait anymore. Make a patty or a loaf and cut away. If it crumbles too much, add more water (slowly) and work it in.

[pyrogeorge]

when i make cut stars,i wet the composition until looks like as plasticine..

if the binder is dextrin,i use 90% water and 10% alcohol and the stars are very hard..

[guntoteninfadel]

as an alternate to cutting them, I have found the florescent diffusers work wonderfully! perfect square little stars every time.

[Potassiumchlorate]

Nater,

 

What did you use as a binder? SGRS doesn't like alcohol.

I wet my charcoal comps ,press it in the bottom of the bucket/bowl, cover and let it set for 10-20 minutes, give the binder time to activate.

 

That might be the problem with my SGRS. It seemed like a nice binder, but with 25/75 alcohol water it doesn't seem to work. Should I use pure water with SGRS?

[pyrojig]

as an alternate to cutting them, I have found the florescent diffusers work wonderfully! perfect square little stars every time.

 

I have had luck with these diffusers as well, but it is hard to remove the stars if the diffusers are not a true square( as when they have a bevel to them. ) Most of the time you have to stack two and glue together so your stars are "squares" not wafer looking squares.

[50AE]

SGRS is specific with the fact that it doesn't like the slightest bit of alcohol. You should use 100% water when binding with SGRS.

[dan999ification]

i mix charcoal comps in a bag aswell you may need more water im not scared of over wetting them ive used over 40% before but not so much that it leaches out if you squeeze it, they just burn quicker due to the more pourous structure and of course take longer to dry i never prime charcoal stars until they dry to prevent driving in.

recently made a 2oz batch of c6 2x2x2 homemade dextrin [dry in a day] to use as cores with great sucsess you have to be careful when you break them though some wait till they dry but i always gently peel them apart and spread them out to dry quicker then re kneed the rest if there is any unwanted different sized bits.

if larger stars are needed i will just pump with 5-12% water and tap the rammer/pump with a mallet to get hard stars

 

dan.

edit if you over wet charcoal star comp screen it spread it out and wait for it to dry a bit

Edited October 9, 2011 by dan999ification

[Karlos]

For wetting charcoal type composition and making good (crumb) dough, is better big porcelain grinding mortar with pestle, or bowl. Wetting must be done too with optimal press to concretion and minimalize air content. SGRS give better result than dextrin, mainly in plasticity during slicing and hardness after drying.

Watch 4:35 time in http://www.youtube.com/user/HajdaHanabi?feature=mhee#p/u/5/VH9s0YFEbdo Wooden frame and sharp knife is very important, if you want perfect cubes. Internet share many silly instructions, which lead to making muddy cake and irregular pseudocubes.

 

http://uchiage-hanabi.com/image/jpg/manufacture/kiriboshi.jpg

http://uchiage-hanabi.com/image/jpg/manufacture/kiriboshi_dry.jpg

Edited October 9, 2011 by Karlos

[Mumbles]

I do use a touch of alcohol when wetting all of my mixes, even those bound with SGRS. It helps to break the initial surface tension that some compositions can exhibit. This is maybe 10-15mL at the most in a kilo of composition, so it only a few percent. 25% is definitely going to cause problems though.

[Potassiumchlorate]

I usually just cut parlon stars. They won't be perfectly cubic in shape, but that is the easist way to make them.

 

I've tried SGRS in pumped stars mostly. I think that, just like Mumbles says, you need some alcohol to break the surface tension.

[chuck45]

Hello everyone, I'm new here.

 

I find that as with most things, practise helps. I use mostly cut stars also.

 

Just a quick question, is there a formula for how much granulated BP to use, to lift a single star of a given weight, from a tube? Have been googling to no avail. I always test stars by firing from a tube, and wondering if there are any proper calculations for charges.

 

Thanks everyone!

[Potassiumchlorate]

I use 1.5 grams for 8 and 10 mm stars.

[chuck45]

Thankyou Potassium chlorate.

 

I had a couple of tweaking issues of late, as I've started making high speed/quality blackpowder. Its awfully fast and blew one tube out the side, with a loose star in the tube and no wadding. Trying to strike a balance between star hieght and blowing them blind. All fun!

[californiapyro]

hmm that shouldn't be an issue, how thick are your tubes? and what's the granulation size?