R-Candy flashpoint / casting to 1/2" aluminum motor

Hi all,
I am new to the hobby and to this thread. I did launch commercial kits with B, then C motors.
Now I want to make a small R-candy based motor. I'm using a 1/2" aluminum tubing for the motor body.
I am planning to experiment with nozzles and expect many test burns before it gets to actual launch. Aluminum is good for experimenting - just wash it and it is ready again.
Safety first, so I've practiced cooking *inert* R-candy first, using table salt instead of KNO3. I used a metal rod to push inert fuel into the motor, but melted sucrose freezes fast, so I had to keep the motor hot by blowing a heat gun at it. I won't be able to pack fuel tightly into the motor without using the heat gun, so here are my questions:
1. What's the best way to cast r-candy into an aluminum tubing? The problem is that melted candy freezes up fast - as soon as it enters the tube and long before it reaches the bottom. I know that there should be no air pockets inside the motor, so I want to make sure that the fuel is packed tightly in the motor.
2. Is it safe to keep hot (or melt) R-Candy with a heat gun (I have an orange one from Harbor Freight) ? I want to make sure that the fuel can't ignite from the heat gun. What is the flashpoint of R-Candy?
Thanks all.

Be warned that motor building is a restricted subject in this group and this will be deleted.

For more info you would be better off seeking membership in the Amateur Experimental Rocketry group on facebook and taking a look at richard nakka's site.

raptor22 said:

Be warned that motor building is a restricted subject in this group and this will be deleted.

For more info you would be better off seeking membership in the Amateur Experimental Rocketry group on facebook and taking a look at richard nakka's site.

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I thought that only motors above certain size are regulated. I'm working on the motor that is only class A or B.....

>> Amateur Experimental Rocketry group on facebook
I am not a fan of facebook (I know, that is unusual to hear). Is there any alternative? Any forum or discussion group?
Thank you.

It's a forum rule, not a law. Posting motor making information of any kind opens the forum owners to liability so they require you prove you have HPR certification so you have a certain base level of competency with rocketry.

There really aren't any comparable groups, the only active experimental rocketry groups i know of are the TRF restricted forum and the one on facebook. I'm not the biggest fan of Facebook either, but you don't need to maintain your account just to make one and join a Facebook group. The people who run the group are spearheading the sugar shot to space project so it's a good group to be a part of.

Thank you, I've sent request to join Amateur Experimental Rocketry.
I also found Experimental Amateur Rocketry on facebook, but this group doesn't seem to be active:
https://www.facebook.com/groups/591372921000307/

The group is active, but you must be a member and level 2 to read or share.

The inactive group that I mentioned is Experimental Amateur Rocketry, not Amateur Experimental Rocketry.

The public TRF is dedicated to hobby rocketry using commercial certified motors and does not permit discussion of amateur motor making. For high power certified TRF members, there is a private restricted access research forum where this topic can discussed by qualified individuals.

Making your own rocket motors is dangerous, and even more so if you do not know what you are doing. The method and manner you describe to make sugar motors is dangerous and could result in accidental ignition. If you spend 10 minutes googling the topic you will find several websites that have information on sugar motors.

Having said that, we do not encourage you to make any rocket motors until you are high power certified since you simply do not have enough knowledge or experience to do it safely. Find a local rocket club and become a member of a national organization and become high power certified. Then you can join our research forum and find a mentor.

Bob Krech, TRF Administrator

As a believer in the free flow of information, here are some places to find the information you seek. Education is the key to doing anything safely.

https://www.nakka-rocketry.net/

https://www.jamesyawn.net/

The james yawn site has a tutorial for exactly what you want to do. I would suggest using sorbitol it melts at a much lower tempature.

tmacklin said:

As a believer in the free flow of information, here are some places to find the information you seek. Education is the key to doing anything safely.

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It's not a question of the free flow of information. It is about providing information to people who are not qualified to use it, having them blow themselves up, and then having the BATFE change their mind and start regulating propellant. Bad for us all.

Bat-mite said:

It's not a question of the free flow of information. It is about providing information to people who are not qualified to use it, having them blow themselves up, and then having the BATFE change their mind and start regulating propellant. Bad for us all.

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Cat is already out of the bag on that one. Between youtube, alternative social groups, and Richard Nakka, sugar propellants are more accessible than ever before. Refusing to provide reliable information to the people who want to build low power sugar sugar will generally just mean that they go elsewhere for their information. The source they find may or may not be a reliable one.

The general consensus is that EX with APCP is safer and more reliable, with its heat-free casting process and reduced rate of grain fracture. Reducing the barrier to entry for APCP by providing free and open access to information would improve the safety of everyone involved, IMO. Do you really want some teenager posting on youtube to be the most accessible source of knowledge on the subject?

raptor22 said:

Cat is already out of the bag on that one. Between youtube, alternative social groups, and Richard Nakka, sugar propellants are more accessible than ever before. Refusing to provide reliable information to the people who want to build low power sugar sugar will generally just mean that they go elsewhere for their information. The source they find may or may not be a reliable one.

The general consensus is that EX with APCP is safer and more reliable, with its heat-free casting process and reduced rate of grain fracture. Reducing the barrier to entry for APCP by providing free and open access to information would improve the safety of everyone involved, IMO. Do you really want some teenager posting on youtube to be the most accessible source of knowledge on the subject?

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I see your point. It's a lot like kids and sex ed, eh?

Bat-mite said:

I see your point. It's a lot like kids and sex ed, eh?

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One oops and it changes your life forever....

While I respect the TRF rules regarding propellant discussions I don't think they were put in place to protect the general population. If memory serves, when Troj was running this place he ran afoul of some alphabet agency and that led to restrictions that are in place now. The two links that Ted added are among the better sites for this kind of information IMO. My take is that when and if I get the urge to home brew, I will seek out locals who do this kind of thing and not rely solely on Internet knowledge.

raptor22 said:

Cat is already out of the bag on that one. Between youtube, alternative social groups, and Richard Nakka, sugar propellants are more accessible than ever before. Refusing to provide reliable information to the people who want to build low power sugar sugar will generally just mean that they go elsewhere for their information. The source they find may or may not be a reliable one.

The general consensus is that EX with APCP is safer and more reliable, with its heat-free casting process and reduced rate of grain fracture. Reducing the barrier to entry for APCP by providing free and open access to information would improve the safety of everyone involved, IMO. Do you really want some teenager posting on youtube to be the most accessible source of knowledge on the subject?

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That is precisely the point I was trying to make. Thanks!

I can't help but think of the fire at CTI. Trained professionals following safety procedures had a fire in which three people were injured; one of them seriously. And on a recent episode of Mythbusters they tried making sugar motors. Adam had a pan of melted sugar shatter on him and he was lucky not to get seriously burned. In the end, they finally sent off their sugar to be cast into motors by someone else as they deemed it too difficult to do safely.

So if people are determined to do this, they need to know it is potentially very dangerous and they must take precautions to safeguard themselves AND others.

Zeus-cat said:

I can't help but think of the fire at CTI. Trained professionals following safety procedures had a fire in which three people were injured; one of them seriously. And on a recent episode of Mythbusters they tried making sugar motors. Adam had a pan of melted sugar shatter on him and he was lucky not to get seriously burned. In the end, they finally sent off their sugar to be cast into motors by someone else as they deemed it too difficult to do safely.

So if people are determined to do this, they need to know it is potentially very dangerous and they must take precautions to safeguard themselves AND others.

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Bingo!

Well, one could always take up stamp collecting. :yawn:

Zeus-cat said:

I can't help but think of the fire at CTI. Trained professionals following safety procedures had a fire in which three people were injured; one of them seriously. And on a recent episode of Mythbusters they tried making sugar motors. Adam had a pan of melted sugar shatter on him and he was lucky not to get seriously burned. In the end, they finally sent off their sugar to be cast into motors by someone else as they deemed it too difficult to do safely.

So if people are determined to do this, they need to know it is potentially very dangerous and they must take precautions to safeguard themselves AND others.

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I think this is a pretty important point. Maybe it's just hangover from Saturday's watching a middle school TARC team lawn dart two rockets and CATO a third and the students be so excited about how awesome those flights were. A parent was capturing video from 4 feet from the launch pad while the countdown was going. A lot of people don't have an appreciation for the dangers of the hobby*. I think that's especially true of the middle school to early college students who come here and want to brew motors after launching 4 BP C motors.

I understand why TRF doesn't want anything to do with research except in the restricted forum. Is there a middle ground where there could be a sticky thread of other places on the web that tell you how to do this reasonably safely? You definitely don't want to get EX propellant safety info from Some Dude on YouTube any more than you want to get sex ed from internet porn. If the Nakka site is reasonably up front about risks and safety info, can we just point people there?

* I don't think rocketry is any more dangerous than say soccer if the NAR/TRA rules are followed. In the examples above, if the parent had been 4' from the launch when it CATO's he would have had a bad day. Minimum safe distance largely solves that. Likewise, most of the other major risks can be reduced to reasonable levels by following the rules and respecting the power of the rockets. No need to take up stamp collecting (plus, think of the dangers of paper cuts! You could get tetanus and die off of one of those. )

boatgeek said:

I understand why TRF doesn't want anything to do with research except in the restricted forum. Is there a middle ground where there could be a sticky thread of other places on the web that tell you how to do this reasonably safely? You definitely don't want to get EX propellant safety info from Some Dude on YouTube any more than you want to get sex ed from internet porn. If the Nakka site is reasonably up front about risks and safety info, can we just point people there?

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The sex ed analogy is a great one.

I get where the forum administrators are coming from here, but also think there has to be a better solution for the safety of all involved. If reputable sources are the most popular and readily available, then those sources can ensure that all information is presented with a strong emphasis on safety. As a result, most experimenters would be fully informed of the risks and best practices.

In the absence of some major policy change, I think stickies linking to outside sources like Richard Nakka's site would be a good middleground.

raptor22 said:

The sex ed analogy is a great one.

I get where the forum administrators are coming from here, but also think there has to be a better solution for the safety of all involved. If reputable sources are the most popular and readily available, then those sources can ensure that all information is presented with a strong emphasis on safety. As a result, most experimenters would be fully informed of the risks and best practices.

In the absence of some major policy change, I think stickies linking to outside sources like Richard Nakka's site would be a good middleground.

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I agree that we need a sticky on this subject. I am throwing this out as a first draft.

This forum is for the discussion of model rocketry using commercially made motors. The discussion of making homemade motors is not allowed in the general forum. Discussions of homemade motors is restricted to a limited access forum. Access to that forum is restricted U.S. citizens who hold high power certifications - no exceptions to that policy will be made.

The manufacture of homemade motors can be very dangerous. No one should attempt making motors without thoroughly researching the topic and taking extensive safety precautions. Three major manufacturers of model rocket motors (Estes, Aerotech and Cessaroni Technologies Incorporated (CTI)) have experienced fires at their facilities while manufacturing rocket motors. These people are experts at manufacturing motors and are doing so following strict safety protocols and yet they have experienced fires and serious injuries. If you still want to make your own motors we urge you to take extensive safety precautions to protect yourself, other people and property.

We do not endorse the manufacture of homemade motors, but if you are intent on doing so we suggest you use these resources so that you have may do so safely.

Works for me, Zeus.

Aerotech had a major fire too:
https://www.berkeleydailyplanet.com...losion--By-Lisa-Snedeker-The-Associated-Press

tmacklin said:

Well, one could always take up stamp collecting. :yawn:

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Watch out for paper cuts!

tmacklin said:

Well, one could always take up stamp collecting. :yawn:

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That's one of my other major hobbies...so there's no doubt of my nerdiness...but it is definitely not a yawner especially if you are a student of history and similar topics. I tend to alternate my free time between working on the collection and building models (plus a few other things that keep me busy).