WindowLicka Posted June 13, 2016 Posted June 13, 2016 This would be funny as hell if it didn't scare the shit out of me every time (2 X's) it happens to me.I go about ramming my milled black powder by hand, using these clever little homemade rocket tools I learned to make over at skylighter.com. It was either there or from one of the AFN Compilations that showed how to make a rocket spindle using 3/4" particle board disks for the base and wooden dowels for the rammers. Needless to say they work. To my point.... I've made several decent engines and wanted to add a little POP! At the end of the rockets flight. Since I don't know how to add a heading to the simple lil' bottle rockets I went to YouTube first and saw this video where this person showed him leaving a gap at the end of his motor where instead of BP and a bulkhead, he puts a few micro stars followed by the bulkhead.Then he says for a report you just use flash powder in the end gap instead of stars. So me wanting to try something so easy, I try's it.... It began to lift about a foot or two and then BAM! or BOOM! It explodes way premature. So I try's it again with a smaller rocket spindle engine this time. Oh, and I didn't leave out any rocket fuel for space inside my tube this time. I rammed it normal except I capped it with clay then drilled a tiny hole with aluminum foil wrapped visco (1 1/2") as a makeshift time fuse running to my flash heading. Even with the end burner spindle motor there is no way I can get my flash to work like the dude on youtube's rockets. It seems way too sensitive and blows up. Pointers on making simple bottle rocket reports have eluded me so far. Not for lack of looking for some quality info on the subject though!
Rkteer Posted June 13, 2016 Posted June 13, 2016 What ratio black powder are you using?Are they cored rockets? Have you launched many without a header? Instead of a clay bulk head I would try ramming a delay comp over the spindle if your using a cored rocket. I quite often use tiger tail comp as my delay
Mumbles Posted June 13, 2016 Posted June 13, 2016 I hate to say it, but these are rocket problem not heading problems. Ramming always leaves a little uncertainty in my opinion. It just leads to a little extra uncertainty and variability. Did you change anything? Hammer? Number of strikes? Size of increments? Ramming base/table? If you have any of the BP left over, you may want to try to make one without a heading and see what happens. In all reality, you probably should be able to make dozens reliably before declaring that they work. Even without a delay, end burners should make it to a safe heights before setting off the heading. It's a bit more helpful with core burners. In either case, it can make the rockets easier to track. I'm partial to glitters and titanium containing compositions.
Mike Posted June 13, 2016 Posted June 13, 2016 Get your rockets working w/o a header. Then you add a tube with the i.d. of your rocket o.d. over the rocket head that is used as the header.
WindowLicka Posted June 13, 2016 Author Posted June 13, 2016 I hate to say it, but these are rocket problem not heading problems. Ramming always leaves a little uncertainty in my opinion. It just leads to a little extra uncertainty and variability. Did you change anything? Hammer? Number of strikes? Size of increments? Ramming base/table? If you have any of the BP left over, you may want to try to make one without a heading and see what happens. In all reality, you probably should be able to make dozens reliably before declaring that they work. Even without a delay, end burners should make it to a safe heights before setting off the heading. It's a bit more helpful with core burners. In either case, it can make the rockets easier to track. I'm partial to glitters and titanium containing compositions. Your right, I was looking at them as explosion problems. My BP is 70/20/10 and as of this posting I'd say my process is chaotic to put it mildly. Not intentionally chaotic to the point of being an accident waiting to happen. But I tend to wing it with the number of strikes, where I ram it, ect. My increments are always the same but the rest of my process could use some refining to make it repeatable and maybe, just maybe, not rush it like I tend to do.An endburner is the nozzleless rocket I believe and I thought I'd have the best luck curbing premature exploding of the header (whenever I get there) by using one these. They have the shorter spindle, right?Funny how you should say the core-burner would help more. Due to rushing my core-burner spindle I'm currently unable to make them for now. I just need to put together another one and clamp it good and let the glue cure this time. But because the spindle is so long on the core-burner it blew up as soon as the fuse hit the powder just pass the nozzle. I don't think I rammed it anywhere near correctly and the spindle broke on removing the tube/motor from the tooling .Definite EPIC FAILURE. I'm gonna get my rocket making process repeatable as of today. I'm off to do just that. thanks.
Rkteer Posted June 14, 2016 Posted June 14, 2016 There are two main types of rockets,Coreburner and endburner. Coreburners have a core (hollow section) this allows for more surface area to burn at once. You need to use a slowish fuel with coreburners to avoid Cato.I use 60 30 10 Endburners have no core ( or a very very small one) and use a fast fuel. These burn for longer go higher but cannot carry much weight. Nozzle less is a coreburner but instead of the clay nozzle there is just black powder forming the nozzle and core. I don't believe any endburners can generate enough thrust to fly this way. The advantage of nozzleless rockets is they can still lift like a standard coreburner but can use hot fuel and don't Cato.
rogeryermaw Posted June 15, 2016 Posted June 15, 2016 (edited) I had some quality rocket tools made by a member here but as for technique, how I got my motors to fly consistently (without a press) was to learn to feel when the grain was solid. If you have a good solid ramming post, with no give, you can feel it in your hammer hand when additional strikes no longer alter the grain. There are many signs. It will change the feedback your hand receives from each strike and the sound loses its soft quality and becomes sharp. Consistency is also key. You want to use the same force each strike and develop your technique until it becomes habitual. Worked for me anyway. Mumbles is right. Get consistent motor performance before strapping burning liability to the end of them. That said, what worked for me was to use gum tape to roll a tube same o.d. as the motor. Fill with various effect, then fuse the header(fast or slow depending on desired effect). Prime the end well. I use thin n.c. to saturate the last 1/4" of the fuse then dip in mill dust. Drill the bulkhead BY HAND ONLY!!! with 1/8" bit. Poke fuse into this hole and, holding your header on the motor straight and even, wrap a couple turns of gum tape around the joint. I have yet to have a rocket fail this way Edited June 15, 2016 by rogeryermaw
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