al93535 Posted March 19, 2009 Posted March 19, 2009 Ok I have been working on my double voice crackers so I can have a few on the 4th. This video is from a recent test. It is however not as good as theone I will be videoing tomorrow. This cracker starts to come back to the ground before it booms the second time so its not good enough. I have now added Ti to the flash, boosted the room for the 4fa and the flash, reduced the time from lift to report and basically made them cool If desired I can post detailed construction plans/instructions as well as pictures. doublevoice3_12_09.wmv
firetech Posted March 19, 2009 Posted March 19, 2009 The contruction plans would be a nice thing to have.
Richtee Posted March 19, 2009 Posted March 19, 2009 (edited) Ok I have been working on my double voice crackers so I can have a few on the 4th. This video is from a recent test. It is however not as good as theone I will be videoing tomorrow. This cracker starts to come back to the ground before it booms the second time so its not good enough. I have now added Ti to the flash, boosted the room for the 4fa and the flash, reduced the time from lift to report and basically made them cool If desired I can post detailed construction plans/instructions as well as pictures.Hmm can't get the vid to work... OK on edit..and this happens here ALOT.. it DL's with 2 extensions.. .avi.wmv weird.. Edited March 19, 2009 by Richtee
al93535 Posted March 20, 2009 Author Posted March 20, 2009 Ok here is the finished item, you cannot see the glittering tail from the prime/tail mix because of the bright daylight, nor can you really see the titanium sparks. I will get video of one at night time to better show those features. I will write up a detailed procedure on the construction of these items tonight. doublevoice3_19.wmv
Richtee Posted March 20, 2009 Posted March 20, 2009 Ok here is the finished item, you cannot see the glittering tail from the prime/tail mix because of the bright daylight, nor can you really see the titanium sparks. I will get video of one at night time to better show those features. I will write up a detailed procedure on the construction of these items tonight. Cool...soo.. is it correct that a DV cracker is really a mini-mortar salute device?
TheSidewinder Posted March 20, 2009 Posted March 20, 2009 Even with the daylight-muted effects that still looked very good, Al. Great job!
psyco_1322 Posted March 20, 2009 Posted March 20, 2009 Thats about right Richtee. I'm not sure if they are actually supposed to shoot clear into the air and go off like a mini shell. Its the general concept that its set on the ground, up right and it pops once then pops again. I thought it was just a hopping type of effect where it just pops up a few inches and lands again. Maybe al93535 just likes his like that. I dont really know, but I've read about them numerous in places and times, just never played with them. I wanted to create a mini salute mortar that fired a 1-1.25" salute up to about 10 feet. The idea was to get the big thump at a close distance. Obviously safety would have to be applied to where you dont stand right under the thing. Havn't went anywhere with the idea yet.
Mumbles Posted March 20, 2009 Posted March 20, 2009 They're supposed to fly way up in the air like that. Al's go higher than I could ever get them, but same general concept. I could never get them to always fly straight up into the air. The odd one would pop off in a random direction, which added some excitement.
al93535 Posted March 21, 2009 Author Posted March 21, 2009 Ok, First you need to make some tooling. This is simple and requires only some glue, a 5/8" tube and a 5/8" oak dowel. Cut two pieces of the dowel, one at 1.75" long and the other at 3" long. Next cut 1" of your 5/8" tube. Glue the tube to the shorter dowel, make the end of the dowel even with the end of the tube. Let the glue dry. Now drill a hole slightly larger then 1/8" (I forgot what drill I used) to hold the 1/8" Chinese fuse in the shorter dowel this hole HAS to be 3/16" deep!!! Any change in the depth of this hole will alter the timing of the second report in the device. Drill a 3/16" hole in the longer dowel about .75 to 1" deep, then either chamfer the hole or use a 1/4" drill bit and drill 1/8" into the 3/16" hole to enlarge the opening. This end will seat over the fuse, and the larger hole makes it easier to line it up without smashing the fuse. Ok here is how the device is constructed. Put 1" of chinese fuse 1/8" into the hole on the bottom dowel (short one). Place a 2-1/8" section of 5/8" ID tube on that dowel so that it rests firmly against the tube you previously glued to the dowel. Put in one scoop of clay (I use a scoop I made to make it easy, I also use -30 +50 mesh bentonite clay, so I measured the column of the clay for you guys) The column of clay needs to be between .36" and .38" high. Just mark it on your ram dowel and use that if need be. This amount of clay is rather critical, it also plays a large role in the timing of the second report! Press the clay with the ram, the longer dowel with the hole facing downwards to let the fuse extend into it. The short part of the fuse is the bottom of the device where the 4fa goes. The top has the longer fuse protruding from the clay, and this is for the flash. Drill a 5/64" hole 3/8" up from the bottom of the tube, this will accept some 1/16" Chinese fuse. Here is where you may decide to vary from my way, I use a hot burning prime that also glitters when its burning. I put a bit extra into the bottom of the tube for this effect. It is a NC lacquer based prime/glitter. You can prime the fuse if you wish, but it really isn't necessary. However, when using unprimed fuse be careful to cut it square and not damage it. Put in the 1/16" fuse and hot glue it in. Now, flash volume varies quite a bit, I can fit 3.5 grams of flash into the top, however I tried some other flash with cabosil and could only get 1.5 grams in. Personally, I like the denser stuff without cabosil. you can also add some titanium, I add -60 + 80 sponge titanium to mine, 10%. Cap the top. I use a 5/8" paper cap that is commercially made, however any capping will be fine. Turn the device over and put 2.10 grams of 4fa (or equivalent) into the bottom. I also use the same paper cup to seal this end. I did have good success with gluing a 5/8" disc into the end. It was about 1/8" thick or so. so you can just cut little pieces of the end of the rest of your 5/8" dowel. There ya go! Have fun! 1
TheSidewinder Posted March 21, 2009 Posted March 21, 2009 Great tutorial, Al! I believe I'll bookmark this page for the upcoming Summer. My neighbors would love this sort of thing. 1
firetech Posted March 23, 2009 Posted March 23, 2009 Here is a video I found a while ago on youtube. It's just a bit of a tutorial on how the Chinese made them years ago.http://www.youtube.com/watch?v=KKe2h-bT3QY
FrankRizzo Posted April 5, 2009 Posted April 5, 2009 Awesome, Al!! If you were to press a bit of glitter comp in there , and shorten the fuse section a bit to compensate for the additional delay, you could have self-launching glittering aerolites.
psyco_1322 Posted April 8, 2009 Posted April 8, 2009 I just made me up some of this tooling and whipped up a double voice cracker. Well, one of its voices spoke quite louder than the other. It hopped up about 6" and landed on the ground, BOOOOM!!! That gram or so of flash mixed in with polverone was really loud. I used 2.1g of 3Fg with a chipboard cup hot glued in. Al, can you elaborate or some some pics of your end disk installments.
al93535 Posted April 8, 2009 Author Posted April 8, 2009 I use wood glue on the plugs. I only use hot glue on the fuse. I made a tool, its simply a dowel with a piece of tube glued on it so that I can put in the end plugs at the same depth every time. Makes it easy for making many of them, but not necessary. I put the plug in level with the end of the tube. I wipe wood glue around the plug, then press it in. I would try wood gluing the plug in. Also, I can guess my plugs have alot more contact with the tube wall, as you are only using a disc. So perhaps a bit more powder in there? With only a 6" hop, you definitely need either more confinement, more BP or hotter BP, is that Goex? Perhaps using a piece of dowel. Cut it off of a 5/8" rod, make it about 1/4" thick, then glue that in with wood glue. I bet that would do it for you.
psyco_1322 Posted April 8, 2009 Posted April 8, 2009 I'll give wood glue a try. I was actually using a hand made plug made from Pepsi box That dowel rod idea sounds nice also. It was Goex, its say superfine FFFg Superfine Black Rifle Powder, its a really old can. I had some 3Fg before and don't remember it being this fine. Its fast none the less. I forgot to mention I scale it up to 3/4" since I have lots of crappy 3/4" tubes that need using up. What one of yours weigh when its done?
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