Packing a chute?

[tommy]

Do you put the shock cord in the body tube before the chute, or the chute before the cord when packing for a launch?
Prolly a dumb question, but I just want to be sure before I crash my new rockets.
Thanks

 

[JPVegh]

According to Estes: Wrap shoud lines loosely around chute, insert chute then shock cord...

 

[cjl]

I wouldn't wrap the lines around the chute. In general, I would also put the shock cord in first, with the chute on top.

 

[tommy]

You see then this is my predicament, the estes and quest directions say lines around chute, chute in first cord on top, but it seems to me that it would work better with the cord in first, chute on top. In fact, if I pack it that way and blow from the engine end everything comes out fine, I just don't want to fry my shock cord elastic if I go that route. It's been so long since I launched a rocket that I can't remember how I used to do it.

 

[KennB]

I like to pack things in the reverse order they will come out of the tube at ejection so there is less chance of things getting tangled. I use a Kevlar leader attached to the motor mount, if I can, and some elastic shock cord to come out of the tube. This is tied to a small metal ring.

I hook the parachute up to the ring using a snap swivel and tie another length of elastic shock cord to the ring and the nose cone. (I use snap swivels on my parachutes so I can easily change them for the conditions.)

One-and-a-half to two diameters of wadding or dog barf go in, then the Kevlar and elastic, a folded and rolled parachute or streamer with the shroud lines rolled around it, then the rest of the elastic and the nose cone.

I picked all this up from the "old hands" at my club's launches and it seems to work well for them and me.

 

[Commonwealth.Net]

Do you put the shock cord in the body tube before the chute, or the chute before the cord when packing for a launch?
Prolly a dumb question, but I just want to be sure before I crash my new rockets.
Thanks

A lot depends on the size of your rocket!
In general the chute needs to be as close to the nose cone as possible.
Wrap shroud line around the chute to help reduce its size, this also makes it
come out of the body tube easier!

The shock cord would go in first.

Now if you are worried about elastic shock cord you should be !
Today with CHEAP replacement KEVALR cord NO rocket should be built stock.

See my web site for Kevlar cord. Usually a hobby size rocket can be modified
for only $1.00 using our 200lb test cord. This also provides protection for your chute (on smaller diameter kits).

Packing the chute on mid and high power kits in more important so that your rocket will net get a dreaded "zipper".

 

[tommy]

I did buy some kevlar, how long a peice would you use for say a 2 foot rocket?

 

[Gillard]

I did buy some kevlar, how long a peice would you use for say a 2 foot rocket?

i like to go for twice the length of the rocket as a rule of thumb.
personally i use a steel fishing leader as the shock cord mount, attached to a length of Kevlar shock cord, with elastic cord on top of that. I always add in a nomex blanket between the leader and the kevlar. and loose wrap the chute with a sheet or two of estes wadding - just in case.
i add the elastic in to absorb some of the shock in case or early or late deployment.

everyone has their own way of doing things.

 

[jflis]

For what it's worth I wrap the shroud lines loosely around the chute as this helps to keep them from getting tangled. Next, I pack the chute first with the shock cord on top of the chute. The reason for this is, if I have an aggressive ejection charge or failed to put in enough wadding, I would rather the whole rocket come down on a melted parachute than to see the nose cone drift away under full chute as the body augers into the ground due to a burnt shock cord...

 

[gdjsky01]

For me: Shock cord 1st. Then chute. Basically if the nose cone comes off I want the chute next in line. Seen too many rockets tumble recovery with the chute half way out the tube or not at all. Most separations (IMO but have no hard evidence) are from bad mounting, being too old, or being too short. Not from melting. YMMV :wink:

For MR and LMR I loosely wrap lines around chute. For HPR I lay them back and forth in the chute before the final folds.

 

[tommy]

Thanks for all the replies everyone!!

 

[FastCargo]

Quick related question:

What do you experienced guys use for recovery wadding?

Before you go 'Huh? Duh!', when I was in this hobby 15+ years ago, I didn't use recovery wadding because it was hard to get where I lived compared to rocket engines. Instead I used cotton balls (real...artificial ones didn't work well) because they were a lot easier to get, and for some reason, even with the recovery wadding I that I was able to use, I was getting bad results (scorching), compared with cotton balls which, when a few were pulled apart, formed a nice seal.

Fast forward to today, and my second BAR launch day, I decided to try recovery wadding and cotton...same type rockets, same engines, one using the recommended amount of wadding following the instructions, the other with a few cotton balls pulled apart.

The results were I got a slightly scorched streamer with the wadding, but the cotton was fine. Obviously, this isn't conclusive (2 samples does not a statistic make), but it makes me wonder...is there another alternative you folks use? I'd be happy to stick with cotton but it's not fire resistant. Now, I have never had 'flaming balls', but more than a few have come out smokin'.

Any other ideas? Or maybe a different technique with the wadding?

FC

 

[rockets4kids]

I followed the recommended Estes technique when I was a kid and I cannot recall ever having any problems.

However, as a BAR, I have used the following technique exclusively:

https://publicmissiles.com/images/pmlchutepacking.pdf

I am also a big fan of pistons. The only rocket I built at a BAR that required wadding was to test the use of lettuce (I actually used some wild weed with broad leaves) as wading. It worked great!

 

[adrian]

For HPR I lay them back and forth in the chute before the final folds.

So do I, only it's for LPR and MPR. Then I fold the chute in zig-zags, rather than rolling it. Usually I wrap one or two turns of shock cord round the whole lot to make a neat bundle which blows out easily. The rest of the shock cord goes in before the chute. (On a couple of short rockets with hollow plastic nose cones, the chute goes into the body and most of the shock cord goes into the nose because that's the only way it all fits in.)

Streamers are packed the same way - folded in zig-zags, one or two wraps of shock cord round the bundle, the rest of the shock cord into the body followed by the streamer.

Wadding: I normally use cheap toilet paper. However this is first sprayed with some stuff I got from a fabric shop which is intended to make chairs, curtains etc. fireproof. It works well on toilet paper too, meaning I don't drop flaming debris all over the field.

 

[dlazarus6660]

Chute, who needs a stinking chute!:kill:
Just let it fall! Than build another one!
Just kidding!
Toilet paper? I gotta check this out! Flame retardent you say!
Dog Barf is cheap!

 

[skyspike1]

Cheap,safe wadding: Flame-resistant "blown-in" type house insulation, from any lumberyard. The "Green" kind is enviromentaly friendly. For residential/comm. building codes..its flame resistant...and CHEAP. (but dont use fiberglass..bad for enviroment..and not bio degrade...no littering please)