Has anyone had problems with Rockethead Rockets parachutes?

The Rocketry Forum

Help Support The Rocketry Forum:

rocket trike

Well-Known Member
Joined
Nov 5, 2002
Messages
776
Reaction score
0
We got a person who said that they had a problem with the swivels that we use on our Mylar parachutes. They said that the swivel bent and came unhooked for the rocket. they received 3 of our parachutes and said all 3 happen. If you have any of our parachutes can you please let us know of any problems that you have encountered with our parachutes. We are trying to put out the best quaility product we can for the lowest price.

Thank you
Tom
 

SecretSquirrel

Well-Known Member
Joined
Jan 18, 2009
Messages
2,126
Reaction score
11
Hmmmmm, problems with your chutes..... in my experiences ABSOLUTELY NONE. I have several and no problems at all.
 

Stymye

Well-Known Member
Joined
Jan 21, 2009
Messages
7,599
Reaction score
5
no problems so far
I know on some fishing swivels the center piece can slide back and forth ,I just check to make sure it's centered the first time I use it and they usually stay put.
 

slim_t

Well-Known Member
Joined
Aug 18, 2003
Messages
746
Reaction score
0
I've got 6 of your chutes. A couple haven't been used yet, but some have been used several times. No trouble at all.
I also have plenty more chutes that use the same type of swivel and have never had a failure like you described.
I guess there is the possibility that you got a bad batch of swivels.
It seems to me that other parts would fail before the swivel. Those things are pretty strong.

Tim
 

Juaru

Well-Known Member
Joined
Mar 1, 2004
Messages
778
Reaction score
0
I have a couple that I use and have not had a problem. Also, I've sold dozens of them and have not had any complaints directed to me.

John (not Jon) Arthur

www.JonRocket.com
 

DynaSoar

Well-Known Member
Joined
Mar 15, 2004
Messages
3,022
Reaction score
0
Originally posted by rocket trike
We got a person who said that they had a problem with the swivels that we use on our Mylar parachutes. They said that the swivel bent and came unhooked for the rocket. they received 3 of our parachutes and said all 3 happen. If you have any of our parachutes can you please let us know of any problems that you have encountered with our parachutes. We are trying to put out the best quaility product we can for the lowest price.

Thank you
Tom
I did say one of those was an early ejection and I'd take the blame for that one. I also said that despite this I was still impressed with their construction.

But of the three, the one I got back (not the high speed deployment) the wire was stretched out. If I'd have thought about it I'd have retrieved it from the FOD box and sent it.
 

rocket trike

Well-Known Member
Joined
Nov 5, 2002
Messages
776
Reaction score
0
I am not complaining or trying to say this did not not happen. I just want to know if there has been a problem with the swivels. Like I said I just want to make sure the customers are getting a high quaility product. I do under stand that There could have been some bad swivels. I am not pointing the finger at anyone or saying that my chutes did not have a problem I just wanted to find out for I could fix the problem if there is one.

tom
 

DynaSoar

Well-Known Member
Joined
Mar 15, 2004
Messages
3,022
Reaction score
0
Originally posted by rocket trike
I am not complaining or trying to say this did not not happen. I just want to know if there has been a problem with the swivels. Like I said I just want to make sure the customers are getting a high quaility product. I do under stand that There could have been some bad swivels. I am not pointing the finger at anyone or saying that my chutes did not have a problem I just wanted to find out for I could fix the problem if there is one.

tom
Sorry, I didn't mean to sound defensive or accusing. And of course you'd immediately offered to replace them, which I appreciate.

I'm glad to say that rather than replacing them, you've agreed to send me two identical chutes, one with the swivel attached and the other with it not attached, so I can do some testing and see if we can figure out what the problem is/was.

Of course, if it was just a few bad swivels, we may never be able to prove that, but at least we're on the path.
 

Stymye

Well-Known Member
Joined
Jan 21, 2009
Messages
7,599
Reaction score
5
can you post a pic of the swivel ?
 

DynaSoar

Well-Known Member
Joined
Mar 15, 2004
Messages
3,022
Reaction score
0
Originally posted by stymye
can you post a pic of the swivel ?
Me, no. I left it in the FOD box at METRA Saturday.
 

rebar_rocketry

Well-Known Member
Joined
Apr 4, 2004
Messages
395
Reaction score
0
Out of all that I've sold, I've never had a single complaint, either. Sometimes even the best products will have a dud once in a while. I'm not saying that's what happened here. It's just Murphy's law and the odds.
 

slim_t

Well-Known Member
Joined
Aug 18, 2003
Messages
746
Reaction score
0
Originally posted by DynaSoar
the one I got back (not the high speed deployment) the wire was stretched out.
Seems to me, this would have to be a weak swivel, or a really powerfull deployment. :confused:
Was it where the wire coils around itself that stretched out?
If so, then maybe RHR should use some larger swivels. I use larger ones with larger chutes, but I don't know what the strengths are, or what they should be. I mostly just use the larger ones because they are easier to attach to the larger shock cords, not really for strength. Sorry I couldn't be of more help.
I'll keep an eye on mine, and let you know if I see any problems.

Tim
 

DynaSoar

Well-Known Member
Joined
Mar 15, 2004
Messages
3,022
Reaction score
0
Originally posted by rocket trike
We got a person who said that they had a problem with the swivels that we use on our Mylar parachutes. They said that the swivel bent and came unhooked for the rocket. they received 3 of our parachutes and said all 3 happen. If you have any of our parachutes can you please let us know of any problems that you have encountered with our parachutes. We are trying to put out the best quaility product we can for the lowest price.

Thank you
Tom
My apologies to Tom for the delay.

I finally got around to testing the chutes he sent me.

I got two mylar chutes, one on the supplied snap swivel, one without. I put my own heavy duty swivel on that one.

I attached them to either end of a piece of dowel and tested them by folding them up, then driving at an even speed and holding them out the window to deploy. I started at 20 MPH and increased 5 MPH each test. One chute failed at 50 MPH (73 fps, if you want to compare that to your simulator results), the other at 60. Both times it was a shroud pulling loose. Neither snap swivel failed.

It might be that a very high speed deployment might yank the chute hard enough that the swivel would fail before the chute could or at the same time (and one of the failures that I had that started this did also have two pulled shrouds). Not worth risking a ticket to find out. Maybe if I go to another launch at the Hearne TX airport I can try it there.

Note that this was a demonstration, not an experiment. It's a single data point. It'd take many such for the speed at failure figure to actually mean something useful.
 

BobCox

Well-Known Member
Joined
Jan 21, 2009
Messages
1,811
Reaction score
0
Tom,


I have several Rockethead Mylar chutes and I am extremely pleased with their quality and convenience. I have not seen any better Mylar chutes regardless of price.

That said, I was a bit surprised that the snap swivels included with the chutes did not have a locking mechanism.

For comparison, the Hagen's catalog shows a variety of swivels. The Rockethead chutes come with Safety Snap Swivels, shown at the top of page 59. At the bottom of page 59 are Barrel Swivels with Interlock Snaps. For the same weight and comparable price, these are less likely to come unlocked. This style is also readily available at Walmart for less than $0.10 each.

The next step up is the Coastlock (page 57). They cost about 50% more but have about 2X the strength. Doc Damerau did some strength testing on coastlock-style swivels. https://www.rocketmaterials.com/data/hardware/ It is interesting to see the way they distort before they fail.

As you move up to stronger swivels, the price starts to go up pretty quickly. https://www.billfishtacklesupply.com/Swivels/swivels.htm
I think the chute will tear before you break one of these larger ones.

I would recommend switching to the Barrel Swivels with Interlock Snaps to get some extra strength with neglible additional weight or cost.
 

rocket trike

Well-Known Member
Joined
Nov 5, 2002
Messages
776
Reaction score
0
Hello Everyone

We are looking at into the swivels. The price of the swivels that has been looked at here is over twice the amount that I pay the ones that I get right now. I have been trying to keep these parachutes at a low cost even with the price of my Mylar going up. If was to change the swivel I would have to up the price of the parachutes. I guess my question if there is that much of a problem with the swivel to up the price of the parachutes or are these working fine and keep the price down.

Tom
 

rebar_rocketry

Well-Known Member
Joined
Apr 4, 2004
Messages
395
Reaction score
0
How about a standard and a heavy duty version? People could pick depending on their needs and wants. I like 'em just they way they are, but different people want different things.
 

DynaSoar

Well-Known Member
Joined
Mar 15, 2004
Messages
3,022
Reaction score
0
Originally posted by rocket trike
Hello Everyone

We are looking at into the swivels. The price of the swivels that has been looked at here is over twice the amount that I pay the ones that I get right now. I have been trying to keep these parachutes at a low cost even with the price of my Mylar going up. If was to change the swivel I would have to up the price of the parachutes. I guess my question if there is that much of a problem with the swivel to up the price of the parachutes or are these working fine and keep the price down.

Tom
I doubt it's "that much" of a problem. But if and when a problem does occur, it seems like more than not much.

I don't think you need stronger swivels, just hooked snap wires. They're harder to pull open. They often cost the same as non-hooked.

You might also consider not attaching them. Just put them and instruction on how to attach them into the package. That way if someone wants to put on their own heavy duty swivel, they can easily.
 
Top