MrP Posted July 13, 2014 Posted July 13, 2014 Hello everyone. I am a complete newbie, so please take it easy. Pyrotechnics is something iv always wanted to get into, iv made a few smoke bombs with kno3 when I was younger but that was as far as it went. Until recently iv decided to give it a go. Iv bought a 1/2" rocket tool set. And my first attempt in making a rocket was terrible. After lighting the fuse waiting for it to take off instead it decided to explode. I used 75/15/10 ratio and maybe I should of used 60/30/10? Thanks P
dagabu Posted July 14, 2014 Posted July 14, 2014 Lots of variables that could lead to a CATO, what tool set do you have, what are you using to press/pound your rockets, what kind/type of fuse are you using and what tubes are you using?
MrP Posted July 14, 2014 Author Posted July 14, 2014 I just used the rammers that is set came with and pounding with a mallet. 2mm visco and the tubes where from oliverbrowns. If I compact the tube to much would this make it explode rather than it taking off?
MrB Posted July 14, 2014 Posted July 14, 2014 If I compact the tube to much would this make it explode rather than it taking off?Not really. No. It's the other way around, most likely. If you se a slight bulge in the tube, a hint that something is growing inside it, thats ok, but at that point you need to start to look for tube supports to get away with compacting it higher.Seams contradict one and other i suppose... It's like this. Unless you make the tube rupture by hammering in more stuff, it's only going o be better if you compact it more. when the tube starts to break, you need a support to keep it intact, but you can increase the pressure pretty much indefinitely. There isn't much point after consolidating the BP to one solid grain, it's voids and cracks that makes you CATO most the time. The alternative is to long spindle, in combination with to hot fuel. Where did you get the tooling, and what was the details of your BP composition?B!
MrP Posted July 14, 2014 Author Posted July 14, 2014 I got it from oliverbrown.co.uk this one http://www.oliverbrown.co.uk/acatalog/info%5f750%2ehtml I used 75/15/10 should I of used 60/30/10? Many thanks P
dagabu Posted July 14, 2014 Posted July 14, 2014 That's what I thought. Sadly, it's missing a rammer or two, there should be a rammer just about as long as the first with a flat end with a hole. The "convergence" rammer, IMHO is just for the nozzle formation, I would never use it at all for nozzleless and when Ben built my set, I asked for a second rammer for nozzleless. Lets look at your clay and your hammer next. What are they and how much pounding are you doing to consolidate the BP? After that, how are you fusing your rockets?
MrP Posted July 14, 2014 Author Posted July 14, 2014 My second attempt was much better today it flew abit wobbly, in stead of going straight up it spiralled but my third attempt flew perfect. I changed my ratio to 60:30:10 and it seems to work brilliant I also reduced the amount of clay I used. The next step I suppose is to get it to go bang while it's in the air this time haha. I have some 2" shells I'm going to have a play with any ideas on what to fill them with. I think filling them with just flash might be to much. Thanks P
dagabu Posted July 14, 2014 Posted July 14, 2014 Good job MrP, lets see some video of your rockets please?
MrP Posted July 15, 2014 Author Posted July 15, 2014 Apologies for my friends potty mouth. Add a little flash for a bit of a bang this time trim.D95637E0-9B6F-4F9B-8D80-CF5EDCD5AE96.MOV 1
dagabu Posted July 16, 2014 Posted July 16, 2014 Apologies for my friends potty mouth. Add a little flash for a bit of a bang this timetrim.D95637E0-9B6F-4F9B-8D80-CF5EDCD5AE96.MOV Not so thrilled about downloading big files as they can contain all sorts of nasty stuff, perhaps you can upload it to VEMO or YouTube?
Mia Posted July 16, 2014 Posted July 16, 2014 Dag you call that a big file! It went like a bat out of hell no virus on the vid
MrP Posted July 16, 2014 Author Posted July 16, 2014 Thanks Mia, not bad for something that came from a pestal and mortar is it.
MrP Posted July 16, 2014 Author Posted July 16, 2014 Dag the video was downloaded straight from my iphone.
Mia Posted July 16, 2014 Posted July 16, 2014 Thanks Mia, not bad for something that came from a pestal and mortar is it.The designer of the tooling in UK is here they have full support. http://pyro-gear.co.uk/index.html
MrP Posted July 16, 2014 Author Posted July 16, 2014 Ok thanks, iv notice they do a spinal conversion, some things are cheaper on pyro-gear. But it's just Easier to order everything from OB as they have more stock. I am tempted to buy one of them ball mills they are selling. P
Mia Posted July 16, 2014 Posted July 16, 2014 There not up front about their stock I agree but they have everything you need you have to ask, I know OB runs two of their mills and has done for the last two years, yes it is easy to order from one site but new legislation within the EU will soon change that my friend that’s assuming we stay in of course. No spinal conversation but they do a spindle conversation (joke an I phone one) the mill will turn out 400grms of BP in around 4hrs I use 2kilos of lead 20mm balls it works great for me.
MrP Posted July 16, 2014 Author Posted July 16, 2014 Haha bloody prediction txt. Is there any pyro events in the uk? I am how ever in need of some of that Chinese delay fuse they have P
hillbilly Posted July 17, 2014 Posted July 17, 2014 (edited) Good job on the rocketry! I love bp rockets been making them for many years mostly one pounders. 60/30/10 has been my basic fuel for most and I have found ball milling to be the best way to get consistency Edited July 17, 2014 by hillbilly
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