dangerousamateur Posted July 10, 2016 Posted July 10, 2016 Thank you for your reports. Not allowing proper clearance between the drift and tube wall encourages the tube to 'pull down'. Now this is a very interesting question: How much play between tube wall and drift would you guys say is optimal? My impression is that it should be very tight, but still sliding without much friction, so that the fuel cannot get between wall and drift.
DavidF Posted July 10, 2016 Posted July 10, 2016 If you are making end burners, your first drift should be snug in the tube so it is perfectly aligned with the spindle. My Wolters tooling base is sloppy in the tube, and so is the drift. SLD's tooling is better on both counts. If you are making coreburners this is no so great an issue. Steve Laduke is the only toolmaker I know of that makes his tooling bases fit the tube snugly. He also 'peens' his rammers to make them tighter in the tube on the business end. The snug tube fit is a pleasure to work with. The peened drifts are a PITA IMHO. They encourage 'tearing in' of the tube's interior layers, and they prevent the easy escape of air, the enemy of consolidation. Again, Shimizu explains this in F.A.S.T. The other toolmakers do not peen their drifts. They work fine (for me). Some makers of whistle rockets complain that the composition can work its way up between the drift and the inner tube wall and make removal difficult if the drifts are sloppy. I don't have that problem. All my (Wolters) whistle and stinger drifts are sloppy. I believe Vaseline or oil in the composition encourages this, and I use neither. I use wax. Also, with rocket makers using 9000psi on the comp for whistle rockets, that's quite a bit more than 9000 on the first increment due to the area of the spindle. If you use a sloppy tube, squishy propellant, AND a peened drift, what a nightmare it would be to get it out! Composition gets between the wall and the drift on many commercial items. I personally feel that under-sized drifts reduce the amount of friction that pulls the tube down in the first place when making rockets. So, there is less distortion for the tube to 'relax' from. I believe that peening the drifts is the exact opposite of what works best. That's my own singular opinion with no malice intended. 1
dagabu Posted July 10, 2016 Posted July 10, 2016 Dave, Thanks for posting this, I forgot most of what you wrote over time. Could you go over how you add wax into your comps?
pyroman2498 Posted July 11, 2016 Posted July 11, 2016 (edited) I've stored fifty various motors for three months with no noticeable issues. Bp, whistle, ibp, ap, etc. All worked great. I was out of work, and spent my free time making rockets for Winterblast one year. Of course, I ended up putting one of those rockets through an RV with a salute header... but that's a different story. I think you should be fine for the most part... just make them to the best of your ability, ie use small consistent increments and press them.oohh... You're the one who i hear the stories about that rocket from ... that happend a few years ago didn't it ? like 2012 maybe even earlier than that ... Dang Dan.... xD Edited July 11, 2016 by pyroman2498
ddewees Posted July 11, 2016 Posted July 11, 2016 oohh... You're the one who i hear the stories about that rocket from ... that happend a few years ago didn't it ? like 2012 maybe even earlier than that ... Dang Dan.... xD February 2014... fortunately nobody was inside. :/ [Video]
otto Posted July 29, 2016 Posted July 29, 2016 Of course, I ended up putting one of those rockets through an RV with a salute header... but that's a different story. I thought this was the rocket forum, sounds (and looks) more like a missile to me...... So do you know what makes 'em do that? I had one little endburner do that, more or less, when the other dozen or so were just fine. Damaged tube, failed nozzle? I never did recover it to do the post mortem.
ddewees Posted July 29, 2016 Posted July 29, 2016 It's Seymour's fault... Crazy formulas produce strange rockets. I've had some travel close to a half mile traveling horizontal 30 feet above the ground... they're very unpredictable. When they're "ON"... they're really moving... but they get a mind of their own when there isn't enough pressure or they begin to chuff. They were some of my favorite rockets to make because they were so unique... and could travel ridiculous distances... but once I moved to the East Coast, they never worked the same again. I'm not sure if the humidity or elevation had anything to do with it... those were the only two things that changes drastically. I went from ~5000 feet above sea level, to about 6 feet.... and i went from close to zero percent humidity to nearly 90 percent. Other than that... nothing changed... so strange. They have a very distinct sounds when they're "ON"... but I always liked the chuff as well. They're crowd pleasers... as long as they don't go after anyone.
joeyz Posted July 30, 2016 Posted July 30, 2016 (edited) hi team! pleasure to meet everyone! azo and seymour, i love your answers. i too is new to pressing rockets and trying to figure the best BP to make my 1lb (3/4") rockets go as high as possible with a long dreamy tiger tail streamer behind it. my payload is 3" ball shell. i am trying to make a 1lb rocket like the "*Sweet Dreams* Rocket" posted on YOUTUBE by Pyrotex. Have you guys seen this yet? if not, here it is (see below youtube link) totally awesome and im working on the nano3 stars coated with tiger tails. Now im trying to figure out what fuel ratio he used, was it end burner or core? was it nozzled or nozzleless? is it possible that he used nano3 instead of potassium in his BP to get that beautiful orange trail in the sky? or did his change ratio on the potassium and charcoal to produce such an effect. i mean this guy "Pirotex"got so many hits on this awesome rocket. anyways, i too want to know whats the best flexible BP fuel ratio for a 1lb rocket with a 3" payload and can be used with end burner, core or nozzleless. i think after mixing or milling the BP, i can always go back and add pinches of anything to add some pixie dust effects. Speaking of pixie dust, has anyone tried a rocket fuel that can produce fairy fountain effects like the fairy fountain that ned gorski posted on youtube as a ground effects item? it would be cool to have the disney effect in the sky too, where it belongs, tinker bell flying across the sky. Back on the Sweet Dreams rocket... Here is what i figured out from his post to people on youtube on how to make this awesome rocket but he didnt say what the fuel was to produce that awesome tail or if it was a core burner or end burner. *Sweet Dreams* Rocket by Pirotex 3" shell, coated rice hulls, bp burst.Stars comp (coffee grind each chem)55% sodium nitrate25% magnalium (80 mesh)10% sulfer5% charcoal5% dextrinMix in bowl with 45% alcohol.Cut, pump or roll stars.Coat stars with tiger tail comp 2-3mm Rocket: 1LbBP unknown, maybe 70/20/10?????Notes:1. You can use 300-325 mesh aluminum instead of magnalium.2. No prime needed, easy to ignite stars and tt is coated over them. -joe Edited July 30, 2016 by joeyz
mikeee Posted July 31, 2016 Posted July 31, 2016 (edited) Depending on the fuel and the amount of delay grains, the rocket turns into a risk/reward product.Low thrust fuels are difficult to control the direction they end up going in.Long fuel delays allow the rocket to make it to the ground.A Strobe or Chuffer motor usually has a higher thrust fuel in the first fuel grain increments to get the rocket heading in a good direction.A long fuel delay can be used on a motor that reaches a high altitude, too long of a delay and you will be starting grass fires or burning someones crops down. This can get costly when the fire department and the farmer sends you a bill for the damages. Edited July 31, 2016 by mikeee
joeyz Posted August 2, 2016 Posted August 2, 2016 Totally agree. so true, risk assessment is needed. i guess pixie dust out the question unless you use pixie dust mix at 3/4 up the rocket to ensure it gets up there safely. With his experience level of his rocket, I'm thinking he knows he's pushing limits in slower fuel composition and payload balancing act to get that tail stream (assumed charcoal rich) - Noting the rocket wabbling on launch and then again 3/4 into the sky. A strong side wind could change situation. It doesnt look like he added any delay, direct pass fire from end of fuel directly to core shell (quick matched) which seems like a safer thing to do (lower risk) when pushing rocket fuel and weight conditions.
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