Merlin Posted April 1, 2016 Posted April 1, 2016 I have made 4 and 8 oz stick rockets but I am wondering if I can make a motor that can be used in estes model rockets? I know about delay and ejection composition but my question is will a core burner work or does it have to be a end burner?
Rkteer Posted April 1, 2016 Posted April 1, 2016 I can't see any reason why it wouldn't. But I have only a little experience with rocketry. somebody with more experience will be around soon I'm sure. Coreburner would not go as high but go quicker I would think. How come you dont want to build endburners?
lloyd Posted April 1, 2016 Posted April 1, 2016 Many of the Estes motors were "modified core burners"; usually with a fairly short core that would suffice to increase the burn area to what they were trying to 'type' the motor, but little enough not to CATO. If your tubes are strong enough, and your nozzles big enough (or absent), the only thing that will prevent a core-burner from working will be if the rocket's fins stay behind when you launch it! <G> If you're on a SIG where Ed Brown is a member, ask him. He worked for Estes for a long time. Lloyd
pyrokid Posted April 1, 2016 Posted April 1, 2016 In my experience you can make perfectly serviceable retrievable/reusable missiles with core burning engines. They have great lifting capacity, but they take off too quickly to replicate Estes missiles from an aesthetic perspective. I always understood Estes motors to be generally end burners, or modified core burners as Lloyd mentioned. A small core is present to modify burn characteristics, but the core length is small relative to the length of the whole fuel grain. My favorite novelty missiles use 3/8" nozzle-less core burner engines to lift 1.75" shells, and they have these huge outlandish fins. Great fun.
calebkessinger Posted April 2, 2016 Posted April 2, 2016 (edited) nozzle less core burners.That second one was 5 feet tall and weighed 5 lbs. 1 3lb. bp coreburner and 2 1lb coreburners whistle on short spindle I did make some end burner motors for some but they were hit and miss. It was years ago with poor tooling and less knowledge. Edited April 2, 2016 by calebkessinger
OldMarine Posted April 2, 2016 Posted April 2, 2016 nozzle less core burners.That second one was 5 feet tall and weighed 5 lbs. 1 3lb. bp coreburner and 2 1lb coreburners whistle on short spindlehttps://www.youtube.com/watch?v=SN4-hulOsxY I did make some end burner motors for some but they were hit and miss. It was years ago with poor tooling and less knowledge. Jeepers Caleb, between you and Chris I'm gonna die broke. Rocket tools and pyro paraphernalia are alright but I'd planned on a Hooker Cruise or something before I started buying short whistle tooling and supports and PtoFs and BM machines and presses and star plates and whatever the hell you crank out tomorrow!Just kidding.I need all that stuff and nice rockets!
schroedinger Posted April 2, 2016 Posted April 2, 2016 Jeepers Caleb, between you and Chris I'm gonna die broke. Rocket tools and pyro paraphernalia are alright but I'd planned on a Hooker Cruise or something before I started buying short whistle tooling and supports and PtoFs and BM machines and presses and star plates and whatever the hell you crank out tomorrow!Just kidding.I need all that stuff and nice rockets!How do you even live without?
Merlin Posted April 2, 2016 Author Posted April 2, 2016 That's really some impressive rockets. I will have to stick with the small BP rockets. I do have a hydraulic press but no way to gauge pressure.. By the way Caleb I need a spindle check your pm.
lloyd Posted April 2, 2016 Posted April 2, 2016 Merlin,I've been installing common (inexpensive) gauges in bottle jacks for decades. Ned G and I conspired on an article on his site concerning doing just that. You could have that pressure feedback you lack for $15-$20 and a couple-hours' work. LLoyd
stix Posted April 3, 2016 Posted April 3, 2016 Merlin,I've been installing common (inexpensive) gauges in bottle jacks for decades. Ned G and I conspired on an article on his site concerning doing just that. You could have that pressure feedback you lack for $15-$20 and a couple-hours' work. LLoyd Hi Lloyd, do you have a link to the article? Cheers.
OldMarine Posted April 3, 2016 Posted April 3, 2016 This one on Skylighter is pretty inclusive:http://blog.skylighter.com/fireworks/2008/12/how-to-make-a-hydraulic-rocket-press.html
stix Posted April 3, 2016 Posted April 3, 2016 Thanks for the link OM - and also many thanks to Ned & Lloyd for the excellent and detailed "How To". I have made 4 and 8 oz stick rockets but I am wondering if I can make a motor that can be used in estes model rockets? I know about delay and ejection composition but my question is will a core burner work or does it have to be a end burner? As others have already pointed out - yes, a core burner will work. It just depends on what "style" of take-off you want or need. For instance, a bp core burner will take off like "the powers of piss" (for want of a better phrase) whereas an end burner has a more gentle burn profile - although as said, some of the Estes motors have a bore into the fuel a short way up from the nozzle end. This ensures there is a short pulse of increased thrust at take-off, therefore producing sufficient speed out of the launch tower/rod/pole for aerodynamics to come into play and make the rocket flight stable - at least to begin with. I'm actually looking at an Estes C6-0 as I write this. It looks like it has an approx. 3-4mm (1/4") bore into the slug. Personally I enjoy watching a slower take-off, but this has it's downfalls (pardon the pun). I'll never forget some many moons ago, I launched a home-made bp rocket. The pure joy of seeing it slowly and gracefully leave the launch tower, like a beloved Saturn V. This euphoria was soon cut short when the rocket slowly turned sideways, and like a cruise missile looking for it's purpose, sailed off into the distance. Lot's of fun nonetheless Cheers
Merlin Posted April 3, 2016 Author Posted April 3, 2016 Thanks for all the replies. I suspected take off speed would be the difference in core vs end burner. I have end burner tooling coming from Caleb. As for trying to modify the hydraulic press I will look into it. Funny how some of us are a bit gun shy. pressing whistle mix.....the way it sounds has caution written all over! At any rate I just need BP end burners at this point. Thanks to all for the input.
MagicFx Posted September 25, 2016 Posted September 25, 2016 Merlin love the name Calebkessinger Great rockets I am wanting to make some estes 29 mm engine have everything but the one pound end burner
Merlin Posted September 25, 2016 Author Posted September 25, 2016 Caleb can fix you up! www.woodysrocks.com
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