Frozentech Posted March 3, 2006 Posted March 3, 2006 Coating shot with clay works fine and does not have any adverse effect on the star. It is the recomended first layer if using shot because it is so smooth (Introductory Practical Pyrotechnics by Tom Perigrin). I have made thousands of stars this way and have never had a problem with any comp including high charcoal content stars. Lampblack just seems to have different properties when rolling.Here's something I've read that may help. Evidently lampblack is really to bust the surface tension on in any comp mix... Ignore the chlorate and look what he recommended for the lampblack. Lampblack willow star Source: PML, post by Bill Ofca Comments: Preparation: Dampen with 50/50 water/alcohol as it is rolled over a(chlorate) core star or stars containing NO sulfur or sulfur compounds.It helps to slightly dampen the lampblack with pure alcohol before itis mixed with the other dry ingredients. Once thoroughly mixed, itshould still flow as a powder, or too much alcohol was used. If thathappens, allow it to evaporate for awhile until it can be sprinkled onthe rolling stars. Lampblack.........................................12Potassium chlorate................................8Potassium nitrate.................................1Dextrin...........................................1
PyroJoe Posted March 4, 2006 Posted March 4, 2006 I have been looking at motors and parts to buy to build me a nascar star roller from passfire, but i've been thinking about just using my dad's cement mixer. Its a smaller cement mixer, it only holds 2 1/2 cubic feet of cement.. He bought it from harbor freight and we only used it once to put in our fence.http://www.harborfreight.com/cpi/ctaf/disp...Itemnumber=2528 I dont feel like finding all the parts for a star roller and spending any more money than have to, since all that money can go towards more chems and stuff. I was wondering if anyone here has experience with rolling stars in a cement mixer and if it works well for medium size batches. Thanks!
Pyrohawk Posted March 4, 2006 Posted March 4, 2006 Whoa thats cool....that almot looks like the star roller the chinese use in their factories! With a little messing around that might be a cool roller! There is one other option for star rollers. Build a Mini NASCAR roller from the harbor freight rock tumblers like mine.... The only problem is it can only roll small amounts of stars at a time, it can do a little over 500g.
Frozentech Posted March 4, 2006 Posted March 4, 2006 I have been looking at motors and parts to buy to build me a nascar star roller from passfire, but i've been thinking about just using my dad's cement mixer. Its a smaller cement mixer, it only holds 2 1/2 cubic feet of cement.. He bought it from harbor freight and we only used it once to put in our fence.http://www.harborfreight.com/cpi/ctaf/disp...Itemnumber=2528 I dont feel like finding all the parts for a star roller and spending any more money than have to, since all that money can go towards more chems and stuff. I was wondering if anyone here has experience with rolling stars in a cement mixer and if it works well for medium size batches. Thanks! Not personally, but as I've read, most of the fireworks manufacturers use something very similar. Ive read that you just have to remove any mixer vanes, rivets, bolts, etc that penetrate the drum, and seal with epoxy. You'll probably have to work with 15 lb / 7 Kg batches or so, to make it work effectively, at a guess. That is a lot of stars for an amateur ! The Wisconsin Pyrotechnic Arts Guild has a page showing some of their member's star rollers, they are in between the small ones and that cement mixer in size... WPAG star rollers I'd love to have one like this myself.
justanotherpyro Posted March 14, 2006 Posted March 14, 2006 I tried out your method pyrohawk. It won't work well for me because the tire has too high a center of gravity. Its a dolly wheel too, and its on wider bigger rollers. It may be that its not wide enough, and flat enough. But other tires are to big. May be worth a try getting it to work right though.
Pyrohawk Posted March 15, 2006 Posted March 15, 2006 Hmmmm.....it works fine for me. I use a GoCart wheel. It's pretty much flat all around like a racing tire. I can get the measurements or a picture if you want.... By to high a center of gravity do you mean the tire falls over?
justanotherpyro Posted March 15, 2006 Posted March 15, 2006 Yes. The shape of the tire is not flat it is rounded. So it doesn't have alot of surface area contacting the rollers, and the high center of gravity makes it wobbly and tip over.
p_y_r_o Posted March 22, 2006 Posted March 22, 2006 sorry for this very Amateur question but how big should a standard rolled star be? Also would 6mm bb's be o.k for cores because because i can't find a good u.k supplier of 2mm bb's.
Pretty green flame Posted March 22, 2006 Posted March 22, 2006 sorry for this very Amateur question but how big should a standard rolled star be? Also would 6mm bb's be o.k for cores because because i can't find a good u.k supplier of 2mm bb's. BB's of that size are crap IMO, you are better off with whole pepper seeds, works great for me. And don't worry about the seeds being uneven, it should produce nice round stars. They are about 3mm in dia.
Mumbles Posted March 22, 2006 Posted March 22, 2006 You could always granulate your composition though a screen and roll off of that. I am personally not a fan of BB's at all. Lead will melt, copper will not, resulting in high speed fall out. Clay could work, it has some tackiness when wet.
justanotherpyro Posted March 22, 2006 Posted March 22, 2006 Buy some birdshot shotgun shells. You get primers for dragon egg type cores, some NC, and lead shot rolling cores.
Pretty green flame Posted April 5, 2006 Posted April 5, 2006 Anyone here know what's the optimal speed for a star roller. I really have no idea.
Mumbles Posted April 5, 2006 Posted April 5, 2006 I would say around 20-30rpm. That is just from seeing live video of peoples star rollers.
Givat Posted April 5, 2006 Posted April 5, 2006 Anyone here know what's the optimal speed for a star roller. I really have no idea. It depends on your star roller size and material. My advice is to build a star roller of about 30RPM and put some cores in it. Then try to change the speed a little until you find the fastest speed when your cores aren't jumping too much and out of the star roller. good luck. BTW, if you are building new star roller I would suggest you to build Nasker roller. From my experience the difference is huge.
Pretty green flame Posted April 8, 2006 Posted April 8, 2006 Me again Well the Japanese use something called "toro" for their stars. The rough i found on the net is that this is a mix of SGRS and some other stuff. Does anyone here have any experience with this type of wetting mix for star rolling. If anyone has their copy of F.A.S.T. from Shimizu i'd really appriciate if they could look it up and write some information here. Thanks in advance.
Chris Posted April 8, 2006 Posted April 8, 2006 Someone posted an extract from Shimizu's Art, Science Technique on using Torro in rec.pyro a few weeks back. The coverage of Torro technique is very narrow in AST, but I'm sure the text will give a few pointers to anyone interested.
somebody Posted April 8, 2006 Posted April 8, 2006 I've looked toro up in shimizu's F.A.S.T.: "First prepare a slurry with water from the same composition as the cut stars of the core.The slurry is called 'Toro'.The viscosity of the toro is important; at first the viscosity must not be too high, because the cores are light and apt to stick to each other.Add water to the toro to adjust the viscosity so the cores do not stick to each other during the operation.As each star grows and becomes heavy, the grains do not stick to each other as much.The next operation increases the viscosity so that the water does not soak into each grain quite as much or so deeply during the operation.Place well dried cut stars in a bowl which has a round base.Pour the Toro on to the stars in small amounts pasting the surface of each cubic star with it by shaking the bowl constantly.Sprinkle powder of the same composition onto the stars and shake the bowl again.The powder adheres on each grain.If the grains stick together separate them by hand or sieving.Repeat the operation; adding Toro and then powder two or three times and then place the grains in the sunshine.If they are left in the shade, the water soaks into the grains, and the grains crumble.When the grains are perfectly dried, repeat the same operation once more, and all the grains will become sferical.Next the grains are coated with a new composition by the same operation according to a colour changing plan.The grains thus grow step by step by the repetition of the coating process.If the Toro remains at the bottom of the bowl during shaking, the amount of Toto is too much; if the powder remains at the bottom, then the amount of powder is too great.Under ideal conditions the bottem of the bowl glistens."........"When the Toro is left for a long time, it generally loses its viscocitydue to the degeneration of the glutinous rice starch and by the action of the other component materials.It must be renewed as far as possible" And don't roll on to thick of a layer because of the change of a driven in batch of stars...
FrankRizzo Posted April 8, 2006 Posted April 8, 2006 A poster over on UKR named JamesH made a Nascar roller hybrid that you guys should check-out. Instead of the tire being driven on the tread, it's fastened to a plywood wheel which is driven instead. http://i11.photobucket.com/albums/a152/jamesh22/5180e6bc.jpghttp://i11.photobucket.com/albums/a152/jamesh22/9372467b.jpg If you look the rest of his gallery, you can see that he's evidentially getting his money's worth from a Passfire subscription.
Frozentech Posted April 8, 2006 Posted April 8, 2006 If you look the rest of his gallery, you can see that he's evidentially getting his money's worth from a Passfire subscription. Nice looking heavy duty star roller he has there ! Yeah I'll say he's getting his money's worth on Passfire... He has written articles for it. He is the developer of the hemisphere center marker that was featured in a tooltip article on there.
weknowpyro Posted April 23, 2006 Posted April 23, 2006 I got this idea of a video i watched were the japnese make round stars by using rice instead of lead balls. I tried this and used my ball mill for it and worked well at the end i had some excess rice but sure enough i had sausage shapped stars. Small but good quality.
somebody Posted April 23, 2006 Posted April 23, 2006 Are you sure they used rice?Rice soaks up water and which makes them grow and might crack the stars. There are more choices then lead, all kinds of seeds are used.Or do you mean rice hulls? because they use a starroller to coat those with meal as breakcharge.
weknowpyro Posted April 23, 2006 Posted April 23, 2006 Well they said rice but im gonna be using these stars as soon as there dry but yea seeds probably would be better.
Mumbles Posted April 23, 2006 Posted April 23, 2006 The Japanese usually use sand or just droplets of water. This takes an extremely long time to be able to do though, so it is not something anyone here will probably be sucessful at. I don't think using rice would be useful until the stars were at least 5/8" or 3/4" in diameter to get them round.
dragonman586 Posted April 24, 2006 Posted April 24, 2006 Actually I somehow managed to pull of the water droplett thing. First I put some comp in a paper cup. Then I spritzd (sp?) with water until I noticed water blobs. Then I agitated it in a circular motion and I ended up with a whole lot of little cores.
Douchermann Posted April 24, 2006 Posted April 24, 2006 Use the same principal with dragon eggs. Granulate the color/effect composition then roll those grains into round stars. Viola! no lead shot, bb's (hopefully you don't use those), or even seeds. The only thing that would fall to the ground would be ash. I'm lazy so I just use 1mm lead shot as those little things wont go that far, even from a powerful burst and plus I have like a 25lb bag of it that I got from my friend. Which I managed to spill once... oh god was that horrible. It was in my house too, not in my garage like where it should have been.
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