Physics xtra credit project: Build two 1-time-use candyrocks

Moderator: Mike Everman

Ray
Posts: 187
Joined: Thu Nov 11, 2004 12:48 am
Antipspambot question: 0
Location: Washington State, USA

Re: re: Physics xtra credit project: Build two 1-time-use ca

Post by Ray » Thu Dec 07, 2006 9:41 pm

heada wrote:If you ask the ATF they will tell you that APCP, ANCP and KNCP based rocket motors are under their regulations. BP motors that contain more than 62.5g of propellant would be under this rule as well.
While they will tell you that these are regulated, their own regulations don't support that. APCP is specifically listed, but ANCP, KNCP, sugar motors and BP motors are not listed.

Nitrate based explosives are listed, but AN and KN motors aren't explosive. For that matter, neither is APCP. Burn rates just don't support it. The lawsuit in progress will prove that out.

The ATF will always err on the side of caution, and if you ask them if something is regulated, they will tell you it is. The law prevents them from saying something is an explosive without evidence to support it.

They have proven over and over again that they don't know what the hell they are talking about, and I believe that the judge presiding over the lawsuit will say the same thing and remove APCP from the explosive list.

The only testing they have actually done on the subject (I've read the report) is so far off the mark as to be funny. They found that bond paper burns faster than APCP in most cases (and it does) and also found that APCP in a J350 motor burns at over 7ips...actual burn rates are much much lower than that. On the order of 1/4 ips...a J350 that burned at 7ips would have a burn time of 0.08 seconds...they took the length of the motor divided the buy the burn time and arrived at a "burn rate". The error they made was that a J350 doesn't burn from end to end, but rather from the inside to the outside, the web thickness is about 1/2 inch and the motor takes about 1.5 seconds to burn...

Sorry for the rant, you've touched a sensitive subject. I'll be the first to comply with the regulations surrounding rocketry, but will also speak up when the regulations don't make any sense, and are based on pseudo science.

heada
Posts: 118
Joined: Tue Nov 21, 2006 4:34 am
Antipspambot question: 0
Location: Indianapolis

re: Physics xtra credit project: Build two 1-time-use candyr

Post by heada » Thu Dec 07, 2006 10:21 pm

Please understand, I agree that the ATF are in the wrong regulating all forms of rocketry propellant. That being said, I too have read the report that the ATF provided to the court. I also know that they calculated the motors as end-burning and not core-burning. They will get this pushed back into their face by multiple sources. I did my own calculations and came up with a H999 motor (one of the fastest burning APCP formulations having an Isp of about 233) to burn at about 1.05ips ((1.308 in - 0.615 in)/2)/0.33 sec

Please read this:
http://a257.g.akamaitech.net/7/257/2422 ... -15850.pdf

"While the list is
comprehensive, it is not all-inclusive.
The fact that an explosive material is
not on the list does not mean that it is
not within the coverage of the law if it
otherwise meets the statutory
definitions in 18 U.S.C. 841. Explosive
materials are listed alphabetically by
their common names followed, where
applicable, by chemical names and
synonyms in brackets

Ammonium nitrate explosive mixtures
(cap sensitive).
*Ammonium nitrate explosive mixtures
(non-cap sensitive).
Ammonium perchlorate having particle
size less than 15 microns.
Ammonium perchlorate composite
propellant.
Ammonium perchlorate explosive
mixtures."
...
"Black powder.
Black powder based explosive mixtures."
...
"Potassium nitrate explosive mixtures."

They do not define what "explosive mixtures" are, so they get to decide on the spot, without consulting anyone (unlawful that it might be). I agree that they shouldn't be on the list and they they're not explosives but I don't get to make up the rules, they do. Until the TRA/NAR win the lawsuit, this is the law and this is what we have to live with.

-Aaron

(edited to correct the Isp of the H999)

Zippiot
Posts: 1190
Joined: Tue Nov 15, 2005 7:55 pm
Antipspambot question: 0
Location: california
Contact:

re: Physics xtra credit project: Build two 1-time-use candyr

Post by Zippiot » Thu Dec 07, 2006 11:18 pm

Do we need to make a separate topic about this subject?
I dont mind if the thread gets off topic, jsut this seems to be important and a devoted thread might help the conversation
Sailing Student- How do I know if my life jacket is tight enough?
Me- Can you breathe?
Sailing Student- Yes
Me- Then its too loose!

marksteamnz
Posts: 408
Joined: Sat Oct 11, 2003 1:42 am
Antipspambot question: 0
Location: New Zealand
Contact:

Re: re: Physics xtra credit project: Build two 1-time-use ca

Post by marksteamnz » Thu Dec 07, 2006 11:48 pm

...
"Black powder.
Black powder based explosive mixtures."
...
"Potassium nitrate explosive mixtures." One of which would be potassium nitrate, sulphur and carbon. ie gun powder. Hmm looks like they are trying to have a bet both ways.

If you have Soduim Nitrate and make gun powder is it also covered?
Typical as it looks like burecrats the world over can't write a clear piece of legislation to save themselves.
Cheers
Mark Stacey
www.cncprototyping.co.nz

Zippiot
Posts: 1190
Joined: Tue Nov 15, 2005 7:55 pm
Antipspambot question: 0
Location: california
Contact:

re: Physics xtra credit project: Build two 1-time-use candyr

Post by Zippiot » Thu Dec 07, 2006 11:53 pm

This is a grey area of the rules...
KNSB propellant will explode in a pvc motor case, does that make it an explosive?

Grey area...
Sailing Student- How do I know if my life jacket is tight enough?
Me- Can you breathe?
Sailing Student- Yes
Me- Then its too loose!

Ray
Posts: 187
Joined: Thu Nov 11, 2004 12:48 am
Antipspambot question: 0
Location: Washington State, USA

re: Physics xtra credit project: Build two 1-time-use candyr

Post by Ray » Fri Dec 08, 2006 12:07 am

it won't explode...it will overpressurize the case and go out. Overpressurization and explosion are very, very different things.

Explosion is a very specific term...not to the ATF but to anyone that works in the field. It is something that has a supersonic burn rate...ie it burns at over 1100fps (approx).

The ATF is trying to define it to include things that deflagrate and now trying to add things that have an oxidizer in a close mix...the definition on their side of things just keeps moving. In short, they don't have a clue. They want to regulate rocket motors and are trying to make the definition fit the thing they want to regulate, in spite of the science that says differently.

Zippiot
Posts: 1190
Joined: Tue Nov 15, 2005 7:55 pm
Antipspambot question: 0
Location: california
Contact:

re: Physics xtra credit project: Build two 1-time-use candyr

Post by Zippiot » Fri Dec 08, 2006 12:17 am

I am sure they are trying to please everyone while keeping us safe. Must be a hard job...

Anyone know the nubmer of deaths or injuries caused by rockets per year, just wondering.
Sailing Student- How do I know if my life jacket is tight enough?
Me- Can you breathe?
Sailing Student- Yes
Me- Then its too loose!

heada
Posts: 118
Joined: Tue Nov 21, 2006 4:34 am
Antipspambot question: 0
Location: Indianapolis

Re: re: Physics xtra credit project: Build two 1-time-use ca

Post by heada » Fri Dec 08, 2006 12:43 am

marksteamnz wrote:
If you have Soduim Nitrate and make gun powder is it also covered?
Further down the list of items...

Sodium nitrate explosive mixtures.
Sodium nitrate-potassium nitrate
explosive mixture.

If the ATF has their way (which it takes a lawsuit to challenge them) they would regulate everything possible.

-Aaron

marksteamnz
Posts: 408
Joined: Sat Oct 11, 2003 1:42 am
Antipspambot question: 0
Location: New Zealand
Contact:

re: Physics xtra credit project: Build two 1-time-use candyr

Post by marksteamnz » Fri Dec 08, 2006 12:43 am

http://www.rocketryplanet.com/content/view/1062/28/
Bother I did my daily check of www.rlv.com and the above link was mentioned about how ATF in the USA are after sugar rockets.
Makes me want to slap the idiot on this forum who wanted to make a guided rocket and "No one would stop him launching anything he made"
I've given up on making hobby rocketry stuff and it's coming off my site. To many cheapskates, to many nutters and this latest. I don't need the aggravation exporting to the USA.
As an aside when I put the hobby rocket items on my site in the following 3 months 25% of the hits were from US millitary. We don't have a lot of traffic so it really stood out.
Last edited by marksteamnz on Fri Dec 08, 2006 6:48 am, edited 1 time in total.
Cheers
Mark Stacey
www.cncprototyping.co.nz

Ray
Posts: 187
Joined: Thu Nov 11, 2004 12:48 am
Antipspambot question: 0
Location: Washington State, USA

Re: re: Physics xtra credit project: Build two 1-time-use ca

Post by Ray » Fri Dec 08, 2006 1:16 am

Zippiot wrote:I am sure they are trying to please everyone while keeping us safe. Must be a hard job...

Anyone know the nubmer of deaths or injuries caused by rockets per year, just wondering.
Thats the point, they are claiming to try to keep us safe...they aren't doing it. Only a total moron of a terrorist would attempt to use a high power amateur rocket for a weapon. The propellants (with the exception of BP) don't work to make any kind of effective bomb. The point is, they aren't doing a thing to keep us safe by regulating APCP. From what I understand APCP has never been used in any kind of attack, ever, not even once...

The number of deaths? Zero, not one, ever.

Injuries? Very, very few, I've only heard of a couple in the years I've been doing this, and those have been pretty minor. I think the worst one was a guy that was hit by a fin on a rocket that didn't deploy a parachute...he required a few stitches.

Greg O'Bryant
Posts: 209
Joined: Mon Mar 14, 2005 4:03 am

re: Physics xtra credit project: Build two 1-time-use candyr

Post by Greg O'Bryant » Fri Dec 08, 2006 3:43 am

check out this thread with my local rocket club

http://www.uroc.org/index.php?option=co ... 94&catid=7

It is a long read but they have discussed this with a litle detail.

Can a terroist make a bomb with sugar propellant? The answere is yes.

If I were a terroist would I apply for a LEUP? NO!
Would I make rocket candy when I could use the same chemicals to make nitroglycerine, TNT, picric acid or just about anyother high explosive that is going to do a lot more damage? No!
Once again just like gun control, all the laws and regulations in the world aren't going to efect the people who don't reguard the law. Last even if they ever got to the piont that they outlawed all chemicals a terrorist could still make chlorates for a bomb! They want to make the illusion of control and safety to get you to give up your freedom. Just a big waste of time, money and an attack on personal freedom.

tufty
Posts: 846
Joined: Wed Dec 24, 2003 12:12 pm
Antipspambot question: 0
Location: France
Contact:

Re: re: Physics xtra credit project: Build two 1-time-use ca

Post by tufty » Fri Dec 08, 2006 8:16 am

Zippiot wrote:I am sure they are trying to please everyone while keeping us safe. Must be a hard job...
Here you are assuming that what is being done in order to "keep us safe" is, in fact, being done for that reason. I see 2 possible reasons here, one requires a more or less tight tin-foil-hat;

"Oh my gh0d, there's people out there launching model rockets that can go a good distance, what would happen if they were to add a payload. Legislate it out of existence, just in case". This is the "never attribute to malice what can reasonably be attributed to incompetence" theory.

Otherwise, there's the "a scared public is a placid and docile public" theory, this requires new "threats" to be discovered, publicised and neutralised by our heros, the government. A small percentage of the population carrying out a harmless and already highly regulated hobby make a good target for this.

"Terrorists" don't care about acting outside the law. They can and will make propellants and payloads / explosives from any number of uncontrolled household items, they have no need to be buying large quantities of chemicals where that purchase will flag up warnings under existing legislation. Why bother pissing about with rocket candy when a vehicle loaded with ANFO rammed into a building is more effective?

In either case, what happens when somone in government discovers pulse-jets.com (especially if they have already discovered Bruce's site)?

Simon

Zippiot
Posts: 1190
Joined: Tue Nov 15, 2005 7:55 pm
Antipspambot question: 0
Location: california
Contact:

re: Physics xtra credit project: Build two 1-time-use candyr

Post by Zippiot » Fri Dec 08, 2006 8:24 am

They would outlaw pj's for fear someone would revive the buzz bomb?
Sailing Student- How do I know if my life jacket is tight enough?
Me- Can you breathe?
Sailing Student- Yes
Me- Then its too loose!

tufty
Posts: 846
Joined: Wed Dec 24, 2003 12:12 pm
Antipspambot question: 0
Location: France
Contact:

Re: re: Physics xtra credit project: Build two 1-time-use ca

Post by tufty » Fri Dec 08, 2006 7:53 pm

Zippiot wrote:They would outlaw pj's for fear someone would revive the buzz bomb?
Google "Bruce Simpson Cruise Missile"

Simon

Zippiot
Posts: 1190
Joined: Tue Nov 15, 2005 7:55 pm
Antipspambot question: 0
Location: california
Contact:

re: Physics xtra credit project: Build two 1-time-use candyr

Post by Zippiot » Sun Dec 10, 2006 11:30 pm

I made a little endburner wrapped in some aluminum foil, just to get a test in on the propellant.

With a 60/40 KNO3 to Sugar propellant a 1.25 inch by 1/2 inch strand burned in about 1.7 seconds. Not too shabby, it was very energetic and readily lit after letting sit in a palstic bag in the freezer for a day. No extra oxidizer shot out the back and 0 residue was left anywhere, good clean burn.

Next I'll do an endburner test of 125grams of propellant (pre-cooked weight), then finally I'll make a simple test motor. Currently I am working on 2 nose cones and 2 rocket bodies tryig to keep them identical...that is turning out to be tricky...


Found some info on an aerospike solid fueled rocket

http://www.nasa.gov/centers/dryden/news ... spike.html
Sailing Student- How do I know if my life jacket is tight enough?
Me- Can you breathe?
Sailing Student- Yes
Me- Then its too loose!

Post Reply