PyroAce Posted August 19, 2012 Posted August 19, 2012 I have seen a lot of times at shows what appear to be spinners which shower out sparks and end with a burst of stars, I'm not sure what their called and could not find a video, I found something similar: http://www.youtube.com/watch?v=V-4Wojmbj9cThey are like that, but instead they start with the spinner not finish with it, I was wondering how they are constructed, would this be how they are made? (please see attachment) Note that the two end tubes are separate, the two tubes are then rolled in a length of kraft paper, the middle of which has the burst and stars. The entire tube is then lowered bottom first (with black fuse hanging off the bottom to be ignited by the lift charge) into the cake tube/launch tube. My theory is that by the time the fuse fire reaches the two holes the spinner is well above the ground, so any erratic flight wont pose a risk to anyone. Also note the black fuse linking the two opposing holes runs along the outside of the tubes, not through it. Alternatively I was also thinking could the spinner insert be made as just one tube with a hole only on one end/side of the tube, would this give enough momentum to spin the tube though? I'm guessing the spinner composition to be some form of aluminium/potassium nitrate mixture?
Mortartube Posted August 19, 2012 Posted August 19, 2012 I think your drawing is far too complicated for a mass produced effect. Imagine the labour in that on a commercial scale. The white stars are undoubtedly Titanium sponge, added to the flash burst. I think that these are normal spinners with a green star pressed in a cavity in the bottom of the tube. The tube would be plugged both ends with a hole in the side for the spinner. A small amount of fierce driver mix would probably be pressed in the tube and have a small flash heading with titanium in the flash. The green star probably lights a small passfire, a pice of raw match maybe when it has nearly burnt out, and this goes into the hole in the spinner. The whole thing would have an outer layer of paper pasted over it (to prevent premature ignition of the passfire), with exception of the bottom where the star is pressed. Either this or it is a very short but firece go getter type star with a green star pressed in a cavity in the bottom and a flah/titanium header.
Bcorso85 Posted August 19, 2012 Posted August 19, 2012 I think your drawing is far too complicated for a mass produced effect. Imagine the labour in that on a commercial scale. The white stars are undoubtedly Titanium sponge, added to the flash burst. I think that these are normal spinners with a green star pressed in a cavity in the bottom of the tube. The tube would be plugged both ends with a hole in the side for the spinner. A small amount of fierce driver mix would probably be pressed in the tube and have a small flash heading with titanium in the flash. The green star probably lights a small passfire, a pice of raw match maybe when it has nearly burnt out, and this goes into the hole in the spinner. The whole thing would have an outer layer of paper pasted over it (to prevent premature ignition of the passfire), with exception of the bottom where the star is pressed. Either this or it is a very short but firece go getter type star with a green star pressed in a cavity in the bottom and a flah/titanium header. Thats why they are manufactured in China Cheap labor no human rights. Small Tourbillion with a green comet.
PyroAce Posted August 22, 2012 Author Posted August 22, 2012 Thank you for the replies I'm going to have a go at making a cake with the driver holes at opposite ends of the tube and also of one with just a driver hole in one end and see how they both perform. I will post results so others can also make thier own if they wish. Does anyone know of a good aluminium powder based driver composition to use that will give off good white spark, is fairly fierce burning but will not explode?
Col Posted August 22, 2012 Posted August 22, 2012 Hot bp with 10% ti sponge would be the way to go. For the tailled spinners in the vid, i`d use an internal core to pipe fire to both ends when the comet burns out. The core will provide extra pressure to get it spinning in a flash. Fireproof the exhausts with a layer of kraft so they survive the lift and burn through the kraft from the inside out. Tooling is easy enough, a base with a nipple the depth of the comet and a pin the right length, plus a hollow rammer..Ram the comet comp last to cover the passfire..
PyroAce Posted August 23, 2012 Author Posted August 23, 2012 Thanks Col, I will also give this ago. The one I am talking about starts with the spinner and then ends with a star burst.
Col Posted August 23, 2012 Posted August 23, 2012 It doesnt seem they`d be difficult to make. Ram 2 spinners and glue a reasonably sturdy (tight fitting) tube liner into the top of one. Add your stars and burst and. glue the other spinner onto the liner.. To save a job, you can put some blackmatch into the exhausts when you`re ramming the spinners...no chance of it falling out that way
Short5 Posted August 24, 2012 Posted August 24, 2012 (edited) This is the attachment: EDIT: Nevermind I didn't read your post well the first time.. Edited August 24, 2012 by Short5
PyroAce Posted September 28, 2012 Author Posted September 28, 2012 I made a small experimental spinners cake before I go full scale, it turned out quite good, the next one I will make will use a revised formulation with coarser aluminum (40 mesh) for better spark effect and I will also be adding a star burst effect for the end of the spinners flight. I ended up just going for the one side hole in the spinner tube, this worked perfectly. I will also be adding more BP lift as I did not take into consideration the extra weight added to a rammed tube that also has clay. These are actually really easy to make, I will be hopefully going for a 100 shot cake which would light the night sky up that's for sure. Video: http://www.youtube.com/watch?v=6kZj0NtAFyA
dagabu Posted September 28, 2012 Posted September 28, 2012 I like them. Cant wait for the star bursts at the end. -dag
PyroAce Posted September 29, 2012 Author Posted September 29, 2012 Thanks dagabu, I can't wait for the 100 shot cake! I will post a video when I fire it.
JFeve81 Posted September 30, 2012 Posted September 30, 2012 Those turned out nice. I like this effect as well. Both starting and ending with spinners. I've made a few before but didn't turn out that well. Gonna have to work on this again.
PyroAce Posted October 4, 2012 Author Posted October 4, 2012 I was sent a couple of PM from people asking how I made them, so I done a quick drawing on the both types I will be making: Basically just find or roll a suitable sized paper tube, make sure it has reasonably thick walls. Ram some clay as a bottom plug. Now either drill or use a metal skewer/nail and push a hole in the tube just above the clay plug. Put some black match in the hole. Ram some composition of your choosing (I will be experimenting a few different formulas to see which works best, I will post my results).Now just ram a top plug of clay and your done with the insert.When you load the insert into your cake tube make sure the black match is pointing down and tucked under the insert to ensure the black match ignites when the lift charge goes off. The advanced spinner with the star burst is the exact same except the tube is longer to accommodate the stars & burst, the top clay plug has a hole in the middle with black match in it which leads to the burst charge. Load your stars & burst in the top cavity, when its nearly full put a cardboard disk on top, either hot glue on top of the disk sealing it (always take precautions when using a hot glue gun around pyrotechnic devices) or fold the remaining portion of the tube over the disk sealing it with glue. 1
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