Quantcast

NAR Rules - Steel BB's for nose cone weight?

The Rocketry Forum

Help Support The Rocketry Forum:

InFlight

Well-Known Member
Joined
Feb 6, 2009
Messages
457
Reaction score
0
My question is.... Can we use steel BB's for nose cone weight?

I'm working on a kit that has a plastic cone and would be easier to glue BB's into the cone rather than using clay.

I'll go with the clay if the rules do not allow this as I am all about following Da rules. ;)

Mods, I was not sure where to ask this question so please move if need be.
Thanks
 

NJnike

Well-Known Member
Joined
Jan 19, 2009
Messages
54
Reaction score
0
As long as you get the proper amount of weight the material is pretty much irrelevant. We've got a guy in my club who uses rice and barley as his nose weight in his scratch built stuff.
 

mjennings

Well-Known Member
Joined
Jan 18, 2009
Messages
1,553
Reaction score
7
My understanding is that for structural components, ie nose cones, body tubes, fins etc metal is "right out" as Brother Maynard would say.

Engine hooks and small amounts of nose weights are OK if they are metal.

How much weight are you talking?

If I'm completely wrong some one let me know and I'll have to go retire a few rockets.
 
Last edited:

InFlight

Well-Known Member
Joined
Feb 6, 2009
Messages
457
Reaction score
0
My understanding is that for structural components, ie nose cones, body tubes, fins etc metal is "right out" as Brother Maynard would say.

Engine hooks and small amounts of nose weights are OK if they are metal.

How much weight are you talking?

If I'm completely wrong some one let me know and I'll have to go retire a few rockets.
Only 0.5 - 1oz of nose weight, it's not a huge amount.
 

tazzdevl1

Well-Known Member
Joined
Jan 18, 2009
Messages
457
Reaction score
0
I use BB's for nose wieght on regular basis. Works great. I would think, since they are not strucural in nature, they are within the NAR Safety Rules.

Cliff
 

shreadvector

Well-Known Member
Joined
Jan 19, 2009
Messages
9,009
Reaction score
196
It's fairly simple:

Think about your rocket.

Think about how it will fly - like how high.

Now, imagine that something goes wrong and your rocket coasts all the way back down without ejecing the nose and hits something (like a fine imported luxury automobile or the top of the skull of the driver of that auto who happens to be an attorney or the top of the skull of the child of that attorney).

Consider the relative safey of a sharp pointy plastic nose cone filled with metal shot epoxied into a solid block of metal compared to the alternatives and the way it will play out as you are cross-examined in the courtroom. What alternatives? Balsa with a weight secured by the screw eye at the aft end of the soft balsa cone. Plastic cone with a softer material inside like sand or clay. Or (*GASP*) larger fins or a longer body that eliminate the need for the nose weight in the first place.

Obviously this is a worst-case scenario, but it can happen (look at the Estes-Cox plastic X-15 with it's pointy nose and super dense nose cone). Yes, people use shot epoxied into cones and so far nobody has been killed or injured. That is probably a result of the rest of the safety code and the fact that at organized launches the rods are angled away from any spectator and parking areas.
 

Fred22

Well-Known Member
Joined
Jan 6, 2009
Messages
2,458
Reaction score
3
Is there not a publication or person within NAR who has addressed this issue minus the usual hyperbole?
Cheers
Fred
 

shreadvector

Well-Known Member
Joined
Jan 19, 2009
Messages
9,009
Reaction score
196
Is there not a publication or person within NAR who has addressed this issue minus the usual hyperbole?
Cheers
Fred
From N.F.P.A. 1122:

4.2 Model Rocket Materials.
4.2.1​
A model rocket’s structural parts, including the body,
nose cone, and fins, shall be made of paper, wood, or plastic

and shall contain no metal parts.


Filling the interior or tip of a plastic nose cone with metal would certainly make the nose cone "contain metal parts".
 

rstaff3

Oddroc-eteer
Joined
Jan 18, 2009
Messages
11,716
Reaction score
10
Technically, so would an eyebolt or altimeter.
 

shreadvector

Well-Known Member
Joined
Jan 19, 2009
Messages
9,009
Reaction score
196
Technically, so would an eyebolt or altimeter.

A Screw eye (as opposed to an eyebolt which is usually much "huger" and has a large nut on the top end) is small and located at the aft end of the wooden nose cone, not "inside" and certainly far away from the inpacting tip of the cone.

No need to argue the fine points here, as the attorneys who represent the estate of the injured or deceased will easily be able to ask you all of the simple and logical questions necessary to determine if any reasonable thinking individual should have known if the method of construction was safe or could have been expected to cause serious injury or death if it hit someone.

Altimeters are usually breakable and not solid metal and are best placed in a tubular payload section and not the tip of a nose cone.

This is all regarding "Model Rockets", and not "High Power Rockets". Construction for HPR is way different and the HPR safety code and distances required reflect this.
 

InFlight

Well-Known Member
Joined
Feb 6, 2009
Messages
457
Reaction score
0
From N.F.P.A. 1122:

4.2 Model Rocket Materials.
4.2.1​
A model rocket’s structural parts, including the body,
nose cone, and fins, shall be made of paper, wood, or plastic

and shall contain no metal parts.


Filling the interior or tip of a plastic nose cone with metal would certainly make the nose cone "contain metal parts".
Thank you, that's what I needed to know.
 

jadebox

Roger Smith
TRF Sponsor
Joined
Jan 18, 2009
Messages
5,674
Reaction score
198
Technically, so would an eyebolt or altimeter.
But, I wouldn't consider either of them to be an actual part of the nosecone while material used to fill the nosecone probably would be.

Whether or not weight added inside the nosecone is a part of the nosecone may be debatable. But, as Fred said, you need to consider it in context. An eyebolt or altimeter is not likely to cause any serious problems if the rocket comes in ballistic. But lead or steel filling a plastic nosecone might be dangerous. Whether or not it's allowed by the safety code, there are better alternatives.

Edit: In response to the original post ... Is a nosecone any safer if filled with clay or metal even though it weighs the same in either case? My guess is that the clay-filled one would be safer because the clay is less dense. But, I'm not certain. It might be an interesting project to test different nosecone and weight materials to see which ones disapate energy better in the case of a rocket coming down without deployment of the recovery system.

-- Roger
 
Last edited:

billspad

Well-Known Member
Joined
Jan 18, 2009
Messages
2,625
Reaction score
2
Is there not a publication or person within NAR who has addressed this issue minus the usual hyperbole?
Cheers
Fred
NAR Safety Committee
Andy Eng
15522 Pleasant Valley
Houston, TX 77062

Be sure to let the rest of us know what he says.
 

dwmzmm

Well-Known Member
Joined
Jan 18, 2009
Messages
1,912
Reaction score
1
Back in the early days of NAR competition (well, when I started competing in
1971 or 1972) the official payload for the Payload Altitude events was a cylindrical lead weight weighing 1 oz. The lead weight had to be enclosed in
your model's payload section and flown to the highest altitude possible (in
the engine class the event called for) and returned safely. The biggest problem I had back then was the extra weight always ripped the shockcord
off and/or the shroud lines from my model's parachute (didn't know about the
Kevlar stuff, or nylon parachutes that we enjoy today). I think even the Estes catalogs back in those days sold these official NAR lead payload weights
as well.

Those were the good ole days.....:rolleyes:
 

dwmzmm

Well-Known Member
Joined
Jan 18, 2009
Messages
1,912
Reaction score
1
Back in the early days of NAR competition (well, when I started competing in
1971 or 1972) the official payload for the Payload Altitude events was a cylindrical lead weight weighing 1 oz. The lead weight had to be enclosed in
your model's payload section and flown to the highest altitude possible (in
the engine class the event called for) and returned safely. The biggest problem I had back then was the extra weight always ripped the shockcord
off and/or the shroud lines from my model's parachute (didn't know about the
Kevlar stuff, or nylon parachutes that we enjoy today). I think even the Estes catalogs back in those days sold these official NAR lead payload weights
as well.

Those were the good ole days.....:rolleyes:
Ok, here's a page from the 1970 Estes catalog; look at the lower left page
and you'll see the cylindrical lead weight I'm talking about. Listed as "Payload"
Cat. No. 651-PL-1

http://www.ninfinger.org/rockets/nostalgia/70est126.html
 

brianc

Well-Known Member
Joined
Jan 18, 2009
Messages
3,220
Reaction score
1
Is a nosecone any safer if filled with clay or metal even though it weighs the same in either case? My guess is that the clay-filled one would be safer because the clay is less dense. But, I'm not certain.
Whenever these discussions come up, I refer everyone to Exhibit A: Styrofoam versus Shuttle Reinforced
Carbon-Carbon...

F=ma folks! Sir Issac was pretty smart to observe that.
 

InFlight

Well-Known Member
Joined
Feb 6, 2009
Messages
457
Reaction score
0
Peartree, RangerStl

I received the information I was looking for from shreadvector.
It was not my intent to start a debate.

Feel free to lock this thread if things get out of hand.
 

evil ed

Well-Known Member
Joined
Jan 20, 2009
Messages
1,611
Reaction score
0
Peartree, RangerStl

I received the information I was looking for from shreadvector.
It was not my intent to start a debate.

Feel free to lock this thread if things get out of hand.
The bottom line to this whole can o' worms is:

Based on your previous kits

A) It will be well thought out.

B) It will be as safe as any other kit on the market.

C) I call dibs on buying kit #1.

'nuff said.

Evil Ed
 

Verna

Well-Known Member
Joined
Jan 26, 2009
Messages
468
Reaction score
0
Ok, here's a page from the 1970 Estes catalog; look at the lower left page
and you'll see the cylindrical lead weight I'm talking about. Listed as "Payload"
Cat. No. 651-PL-1

http://www.ninfinger.org/rockets/nostalgia/70est126.html

Personally, I don't see a problem with bb's as nose weight. I've used small lead fishing weights in several of my rockets, flown them dozens of times each, with no damage, injuries or deaths. Granted, we do tend to over build, particularly the recovery system.

I think you'll find there have been a couple of Estes rockets designed and sold with lead as the nose weight dating back to the late 1970's, the BSG Viper being one of them. The kit comes with 4 lead discs for the nc and the instructions call for them to be tied in with string. I also glued mine in and used a very small mount of clay as a filler to make sure they don't shift in flight.

To be honest I'm more concerned about flying with H powered DVD's than an ounce or two of lead. Especially when they're used for fins.

If you're ever concerned with any construction material, don't use it, lead, bb's or otherwise. Just use what you feel safe with. ;)

Verna
 

Fred22

Well-Known Member
Joined
Jan 6, 2009
Messages
2,458
Reaction score
3
It's okay to ask safety questions. It's okay to render opinions but I know of no other topic on the board that gets people so hot so fast. It's a bit of a shame because it makes discussing an important topic difficult. I have one rocket with the bb's and all the rest use plasticine soaked in epoxy. I think I will refer this interesting question to some friends with CAR and maybe the NAR as well. I like to think of myself as being safe as possible but maybe I need to rethink what I am doing :)
Cheers
fred
 

Fred22

Well-Known Member
Joined
Jan 6, 2009
Messages
2,458
Reaction score
3
Peartree, RangerStl

I received the information I was looking for from shreadvector.
It was not my intent to start a debate.

Feel free to lock this thread if things get out of hand.
See my previous post please :)
Cheers
fred
 

rstaff3

Oddroc-eteer
Joined
Jan 18, 2009
Messages
11,716
Reaction score
10
I made my comment to generate some discussion, which it did.

I'm sure plenty of folks use BBs, lead shot, etc for nose weight in LPR flights at all NAR events. I also don't actually think a screw eye or an altimeter with minimal metal is the same as lead shot embedded in epoxy. However, there is a gray area here and it's clear there will be a variety of interpretations of a simple statement.
 

dwmzmm

Well-Known Member
Joined
Jan 18, 2009
Messages
1,912
Reaction score
1
Personally, I don't see a problem with bb's as nose weight. I've used small lead fishing weights in several of my rockets, flown them dozens of times each, with no damage, injuries or deaths. Granted, we do tend to over build, particularly the recovery system.

I think you'll find there have been a couple of Estes rockets designed and sold with lead as the nose weight dating back to the late 1970's, the BSG Viper being one of them. The kit comes with 4 lead discs for the nc and the instructions call for them to be tied in with string. I also glued mine in and used a very small mount of clay as a filler to make sure they don't shift in flight.

To be honest I'm more concerned about flying with H powered DVD's than an ounce or two of lead. Especially when they're used for fins.

If you're ever concerned with any construction material, don't use it, lead, bb's or otherwise. Just use what you feel safe with. ;)

Verna
The lead weight mentioned in my previous posts WAS the standard (required)
payload for the NAR Payload Altitude events during those years. If I recall correctly, some of the "low" powered payload events required the use of a
single 1 oz lead weight; the classifications where the total impulse power went to the E & F class engines more than one payload was required (I think
up to three or four 1 oz payloads were required; maybe someone who knows
this more than me can chime in as my memory of the NAR Pink Book events/
rules of those days is very fuzzy -- besides, the Payload Altitude events wasn't my cup of tea, if you know what I mean). I also recall during some of
the NAR Sanctioned contests I attended the hosting Section had a number of
these lead payloads on hand (like the hosting Section has to supply the fresh
eggs for the Egglofting events).
 

Porthos II

Well-Known Member
Joined
Jan 18, 2009
Messages
180
Reaction score
0
From N.F.P.A. 1122:*
4.2 Model Rocket Materials.4.2.1​
A model rocket’s structural parts, including the body,nose cone, and fins, shall be made of paper, wood, or plastic
and shall contain no metal parts. *Filling the interior or tip of a plastic nose cone with metal would certainly make the nose cone "contain metal parts".
This definition means no metal engine hooks, eyehooks, altimeters...* As it says NO METAL PARTS.

NAR's safety code is much more lenient...* It reads:
I will only use lightweight, non-metal parts for the nose, body, and fins of my rocket.

Erik
 
Last edited by a moderator:

MarkM

Well-Known Member
Joined
Jan 18, 2009
Messages
2,197
Reaction score
1
F=ma folks! Sir Issac was pretty smart to observe that.
Exactly!!
A nosecone filled with say 450 grams (~1lb) of lead shot will generate the same force (and acceleration) as that same nosecone filled with 450 grams of saw dust. They both weigh the same! Density of the material used is not a variable in the equation.

I don't consider lead or BBs added to a nosecone as structural material. It's ballast. I've used lead and BBs on several rockets that required weight added. In fact, some kit manufacturers, who are well aware of the NAR safety code, include the weight in their kits ... and it isn't sawdust!
 
Last edited:

RangerStl

Well-Known Member
Joined
Jan 17, 2009
Messages
1,080
Reaction score
1
This definition means no metal engine hooks, eyehooks, altimeters...* As it says NO METAL PARTS.

NAR's safety code is much more lenient...* It reads:
I will only use lightweight, non-metal parts for the nose, body, and fins of my rocket.

Erik
Motor hooks, eyelets and altimeters are not structural. The aim is to keep rockets from being made from conduit, sheet metal, and funnels... Seriously.

If the NFPA quote is a real quote, their wording is bad. Don't make metal finned, metal tubed, or metal nosed rockets. If you need a little ballast, don't form it into the skin of your nose cone. Don't make your ballast a sharpened barbed point on the tip of the nose. Structural parts from paper and wood. Structural. Structure gives form, shape and support. Ballast is not structure.
 

Fred22

Well-Known Member
Joined
Jan 6, 2009
Messages
2,458
Reaction score
3
Motor hooks, eyelets and altimeters are not structural. The aim is to keep rockets from being made from conduit, sheet metal, and funnels... Seriously.

If the NFPA quote is a real quote, their wording is bad. Don't make metal finned, metal tubed, or metal nosed rockets. If you need a little ballast, don't form it into the skin of your nose cone. Don't make your ballast a sharpened barbed point on the tip of the nose. Structural parts from paper and wood. Structural. Structure gives form, shape and support. Ballast is not structure.
This makes serious sence :)
Cheers
fred
 

Peartree

Cyborg Rocketeer
Staff member
Administrator
Global Mod
Joined
Jan 6, 2009
Messages
5,002
Reaction score
558
Location
Alliance, Ohio
The whole conversation reminds us to think things through. Last year I built a scratch rocket as a part of the EMRR challenge that needed to look like one of the spaceship pictures posted there. I came close. I test flew the bird before painting but to make it stable I loaded the paper nosecone with epoxy and lead shot. So much lead shot, in fact, that it frightened me a little.

The up part was fine but a recovery failure (likely due to cold weather) doomed the down part. I've been thinking of a rebuild but if I do, the body will be six to twelve inches longer and maybe the fins a bit bigger so the weight in the nose can be significantly reduced.

A little engineering, a little thought, a little common sense and we can keep everyone safe (and not punch any holes in automobiles) along the way.:D
 
Top