Advice required!
- Thread starter Adityaram
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Spend the money.
Making your own propellant requires skills of a level 2 and higher. You are a long way from that.
mikec
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I doubt many people on this forum know much about the rocketry situation in India (I sure don't), and this forum doesn't discuss any kind of propellant making except in a closed area that you can't get access to, so I suggest you seek out experienced rocketeers in your area for better advice. All homemade propellants have their inherent dangers, which can be avoided by using commercial rocket motors.
Titan II
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It is always nice when others spend your money, and the whole level thing is absolutely meaningless when it comes to having any special skills. Here are two of the good sites. Have fun.
https://www.nakka-rocketry.net/https://www.jamesyawn.net/
https://www.nakka-rocketry.net/https://www.jamesyawn.net/
Those 2 sites fall into the 5% that are good resources... just be cautious if the majority of ones which are not.
Still, this is not at a newbie skill level. Nakka is a highly accomplished multi talented determined and methodical person, who has level 2 ++ skills.
My understanding is that half of the custom motors at Tripoli events explode on the pad.
This is misleading. You can get to it, with the proper credentials.
... a newbie does not have the proper credentials...
They definitely have a higher rate of failure than commercial motors, but saying half of them fail is definitely too high in my experience. Maybe a quarter.
IIRC, members outside the US aren’t eligible.
That sounds like a wild exaggeration. If you have actual data from a number of launches to support this claim, please provide it. Otherwise it's merely a claim and is just as valid as "the moon landing was faked" or "any vaccine will kill you within a year."
And IMO it is a claim unworthy of anyone calling him/herself a rocket scientist.
I would say way less then 5%. I think the last one we had at our site was my 54mm 4g that blew up because of how I did the smoke grain. That was almost 2 years ago. We haven't had a EX motor cato since, that I can remember. A few AT and CTI, but no EX.
I can't say how many didn't while work while characterization testing away from the site but the ones brought to the site to fly have been working very well.
You're probably right, I'm just thinking of a couple of really nasty failures I have seen over the past year and that probably caused some bias in my thinking. It's not like I've been keeping a catalogue of them.
I can't really say I've seen some really "nasty failures" at our site. Mine might have been the worse in years, it blew 18" off the bottom of my rocket and split the case down to the last couple inches. It happened about 150 ft. up and I only found 2 of the 3 fins.
Most, if not all, the EX fliers at our club are looking for good dependable, repeatable propellants. No one I know is trying to develop any really high performance mixes so there are very few failures during flights. Can honestly say we see more failures of commercial loads than EX, and even though there are many more commercial flights, those failures are few and far between.
Yeah, higher rates for commercial. My experience too, and stats from 3 TRA clubs.
rcktnut
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Ready-made motors are very expensive here too.
Titan II
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Not even remotely close to what they cost there.
No offense meant. It was a claim that someone made and was wondering how true it was.
Thank you @Antares JS for the clarification.
Bull
John Heska
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There is a book available from Amazon called: "Build It Yourself! PVC Rocket Engine." Written by Dan Pollino. In this book he gives you the formula and how to make it sugar motors and Propellant. Hope that helps.
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I have one for sale if anybody is interested. Pm me and we can agree on price and shipping.
Not in the slightest but true. We have only one flier that comes close to 1/2.
We had a fellow pilot that when I met him I thought his name was Forrest, cause everyone called him that. well, later found out that was his nick name, Forrest Fire, cause he would always hot start the tu
Hot start the turbine and set his plane on fire.
Agree whole heartedly but depends where the training that's been had and the resources the flier has. Sure with non-erosive graphite nozzle stuff, most folks do ground testing to figure out the optimum nozzle throat. Problem is, is having the facilities, lathe and skills to turn nozzles doesn't come easy. Most choose a "little" larger throat size for a first ground test. I had a prefect that had the equipment and would turn anything for a club member as long as they supplied the materials. Did cases too. I had a lot of fun with that.
I did a two grain 38 in an AT case and I had to use an AT erosive phenolic nozzle from a J350 and drill it out a teeny tiny bit and used a thick walled garolite liner. Burnsim can only get one in the ballpark as it assumes non-erosive graphite. AT will sell you motor parts all you want for a price.
Oh, the first self made motor shouldn't be the first one, one flies and should be used for ground testing. Make a large enough mix to make several motors one can fine tune the nozzle throat. It can sometimes be Voodoo. It's easier with erosive nozzles. Oversize a graphite nozzle and one will not blow the case but then have to get/turn and nozzle with a smaller throat if the burn was not optimal. Higher frame rate, closeup video is helpful here to judge the nature of the burn. Graphite is considered non-erosive but I've noticed a build up of "yutz" in the nozzle if it's been fired a few times even with commercial loads. I'm paranoid so I try to restore it to standard stock nozzle throat size with scrubbing before firing with the next commercial load. Gotta have a good I.D. micrometer for that.
I remember from the old "Ex" launch days I was at, the failure rate wasn't even close to 1/2. There were more recovery mishaps than CATO's. Again it depends upon the flier. Flying an untested motor mix the first time is very dicey and I learned never to do that. Oh, I thought in TRA the PVC casings are outlawed? Correct me if I'm wrong. I have that same Pollino book stashed downstairs, read it and really wasn't impressed. If one owns the land to fly a PVC project, they do so at their own risk but they'll be NO support from TRA and especially NAR if there is an "off nominal" flight that results in a mishap. Erosive nozzle and non-erosive nozzle motors are both different ball games! Raw PVC is unsafe as a casing material.
Kurt
Titan II
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1. There is a vast amount of rocketry going on that has nothing to do with TRA or NAR.
2. The PVC matter is open to dispute. If you are at a resonable distance from the pad, it is not an issue. You use what you have.
3. The OP is in India. Not everone in the world have the luxuries we have in the US.
OP....you may also want to read this (complements of US Army Field Artillery School, Ft Sill, OK).
https://aeroconsystems.com/tips/a-guide-to-amateur-rocketry-1.pdf
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