Cluster question - Sunward cables

[paul.nortness]

Hey all,

I am getting parts together for a BT80 upscale of the SCRAM from the Estes Mini Tri Pack. This rocket will be powered be a dual D12 cluster....this will be my first attempt at clusters. I recently found Sunward Rockets makes cluster cables.

Has anyone used these cables? Any feedback on them? I assume that these would require the power of a 12volt launch controller?

Any assistance/advice you could provide on these cables would be much appreciated!

 

[fyrwrxz]

nah- just twist your ignitor leads together (creates two leads) and hook up your regular controller. Should work fine on D's. Use fresh batteries.

 

[jflis]

I would agree that twisting the leads together would be the most reliable solution. Here is a copy of our Hints-n-Tips sheet on clustering. Hope it helps

jim

View attachment hnt-sl3cl.pdf

 

[hcmbanjo]

A few weeks back I flew my first three engine cluster.
I thought I'd need a clip whip for the three B6-6 engines.

If you use the standard Quest Q2G2 igniters, the igniter leads are plenty long to be twisted together without needing a clip whip.
Just be sure the wrong wires don't make contact with each other!
The Estes igniter leads are much shorter than the Quest Q2G2 leads.

 

[bjphoenix]

I built an Astron Ranger over 40 years ago. I used normal 18ga "lamp cord" type wire for wiring my igniters. I would twist 3 leads together in the middle of the cluster, then make a loop with the lamp cord around the outside and twist the other 3 igniter leads around this wire. Connect one of the launch leads to this wire and the other lead to the 3 leads twisted together in the middle. We used 12V car batteries to launch these and never had a failure.

 

[Fe Dude]

I have an estes Super Alpha that I modified to take 3 13mm boosters as well as the standard 18mm motor, I used the estes igniters with a clip-whip once. I found it to be too much of a PITA to try and keep the clips separate from each other. Now I buy the quest Q2G2 igniters for all of my clustering needs. The long leads make it much easier to wire them all together, and as a bonus they need less juice than the estes ones, so you don't need to plug into the main power grid to launch. (Although I did make a homebrew 12V launch controller that I can hook up to a moped battery, or even my car)

 

[stealth6]

I hear all the concerns with using clip-whips, and I see the points being made.

That said, I use a clip whip myself fairly often and I like it. Mine is home made, but it seems to be pretty similiar to what Sunward offers. My main reason for using it is that my rocket motor clusters are made in such a way that twisting the actual ignitors together wouldn't work well; they are too far apart and/or the boattail and fins would get in the way. So a clip whip it is, and so far it's worked out well.

I did have a problem one time though:
I don't believe that the whip had anything to do with it, but still. Basically I had a three motor cluster that had one motor fail to ignite. It apparantly dragged the whip up into the sky with the rocket, and the whip was lost. I searched all over, and even found the unlit motor (which had somehow ejected) but the whip was gone.

So I made another one. And I've used it a lot with no problems.

If you CAN easily twist the actual igniters together, this would probably be a better way to go, but clip whips can and do work well too. YMMV.

s6

 

[UMRS]

A few weeks back I flew my first three engine cluster.
I thought I'd need a clip whip for the three B6-6 engines.

If you use the standard Quest Q2G2 igniters, the igniter leads are plenty long to be twisted together without needing a clip whip.
Just be sure the wrong wires don't make contact with each other!
The Estes igniter leads are much shorter than the Quest Q2G2 leads.

Good point no need to waste money on a clip whip. Save it for more motors

 

[gdjsky01]

Hey all,

I am getting parts together for a BT80 upscale of the SCRAM from the Estes Mini Tri Pack. This rocket will be powered be a dual D12 cluster....this will be my first attempt at clusters. I recently found Sunward Rockets makes cluster cables.

Has anyone used these cables? Any feedback on them? I assume that these would require the power of a 12volt launch controller?

Any assistance/advice you could provide on these cables would be much appreciated!

I'll hop on the bandwagon. Dual D12's should work just by twisting one set together and then the other. I did a dual 18mm last weekend and just twisted them together. I've done 3x18mm's as well and 3x29mm. All of them I just tied the leads together and used a standard two clip setup. I did place extra zip cord on the 29mm cluster to ride up the rail in case of a late ignition, but that won't be needed in your case.

 

[Zeus-cat]

I agree that there is no need for a clip whip for two Estes motors. I always twist the leads together and it works great.

 

[BobH48]

I never use clip whips. I just add extentions to Estes igniters. I use 2 colors to make it easier keep the correct leads twisted together.

Quest G2Q2 igniters would work also but since they have the same color leads on both sides, you need to be a little more careful hooking them up.

 

[Tronman]

I like the Sunward clip whips. They're well made and reliable, as well as convenient. Haven't had a failure, although I add insurance by using the Quest Q2G2 igniters.

 

[RocketManDan]

nah- just twist your ignitor leads together (creates two leads) and hook up your regular controller. Should work fine on D's. Use fresh batteries.

I agree...you will need a 12-volt when firing off maybe 3 plus motors. An "E" launch controller should provide the juice. Not sure about the smaller one? Never used it before?

 

[RocketManDan]

If you were to cluster lets say 2-4 engine clusters using composite motors from 18-29mm could the Quest Q2G2 igniters work in that application??

 

[cavecentral]

I do 4 D12 clusters in my viper IV all the time. Just twisting the wires together.

Put the ignitor in, use the plug to secure it. Gently remove the paper strip. Wire the 8 leads into 4 pairs. Bring 2 pairs together across the middle. Twist and repeat for the other pairs. One strip of masking tale is useful to make sure leads do not touch.

 

[stealth6]

Again, I'll say that I understand the concerns with using a whip - what I don't understand is folks taking that a little too far and thinking along the lines of "I never use them". I get that a whip is "one more thing" in the chain, and therefore one more thing to fail, but it's not all that difficult to ensure a good connection. I also get that in situations like say having two BP motors right next to each, it's easier/cheaper/more reliable to just twist the igniters together.

But there ARE situations where a whip is better. And there really isn't all that much to go wrong with them - ensuring full continuity is no big deal.

Take this example (and refer to the pic in this post):
(and Bob, I don't intend to pick on you, but it illustrates a point)

I never use clip whips. I just add extentions to Estes igniters. I use 2 colors to make it easier keep the correct leads twisted together.

Quest G2Q2 igniters would work also but since they have the same color leads on both sides, you need to be a little more careful hooking them up.

- If Bob is trying to save money, then his solution works great. It makes perfect sense. Why buy a whip if you can simply do this?
- But if he is trying to avoid the potential failure of a whip, then this arrangement makes no sense at all. A clip whip would be far more likely to provide full continuity than this. If this was a 3 or 4 motor cluster, the chances of one of those little twists being faulty is MUCH higher than the solid, soldered connections of a well made whip.
- And if he is trying to make it easier, the whip would still win out. Again, in a 3-4 motor cluster, twisting extensions onto 6 or 8 igniter ends, and then twisting all those together (while "being careful" as he points out) is kind of a pain. Or you could just use those clips to hook it up in seconds.

2 or maybe 3 BP motors right next to each other? - forget the whip and simply twist the igniters together.

3 or 4 canted motors with a boat tail in the way? - I'd use my whip every time.

Every situation is different, and there is no one way that is best.

s6

 

[cavecentral]

Every situation is different, and there is no one way that is best.

Agreed. Every situation and every person is different. I've made clip whips before too. Just try a few things until you find something you are comfortable with.

 

[paul.nortness]

Thanks for the feedback guys. I appreciate all the info!

 

[BobH48]

Bob, I don't intend to pick on you, but it illustrates a point

No problem, it isn't any different than my club members picking on me.

If Bob is trying to save money, then his solution works great. It makes perfect sense. Why buy a whip if you can simply do this?

Money has nothing to do with it. I have several sets of clip whips which I don't use ANY MORE.

But if he is trying to avoid the potential failure of a whip, then this arrangement makes no sense at all. A clip whip would be far more likely to provide full continuity than this.

This is where we will have to agree to disagree. I have much greater reliablity since going to extentions than I ever had with clip whips.

If this was a 3 or 4 motor cluster, the chances of one of those little twists being faulty is MUCH higher than the solid, soldered connections of a well made whip.

Again I disagee. I make these up in advance. I use a wire wrap tool to add the extentions and the igniter wire is bent back over and crimped to the wrap. Each igniter is checked for continuity after being installed in the motor before the ends are twisted together. There is no way to insure that each clip in a clip whip has a solid connection.

And if he is trying to make it easier, the whip would still win out.

There is no contest, all the extentions are pre-made and the ends take second to twist together since the ends are already color coded. You have to be more careful hooking up the clip whip to make sure you get a positive and negative on every igniter.

Every situation is different, and there is no one way that is best.

Ok, I can go along with this. This is one of those things where you are not going to get everyone to agree on which way is best. I personally believe that the extentions are more reliable and easier to use than a clip whip and I'm 100% sure that there are people out there that believe just the opposite.

I will say that I had more failures when I was using clip whips that I have had since switching to extentions. EDIT: And I don't have to worry about forgetting the clip whips at the pad.

I have had one failure recently that I can recall after switching away from whips and I can attribute that to a very weak battery.

 

[stealth6]

Bob, everything in your above post sounds good to me. This is very much a "to each his own" thing - and we are just talking about launching rockets after all. I'm sure we'd have fun launching together (even if we did pick on each other).

The only tiny "correction" I'd say concerns this:

snip... You have to be more careful hooking up the clip whip to make sure you get a positive and negative on every igniter.
.....snip.

I find this is MUCH simpler, easier, and more foolproof when using a whip. If the whip is built right - with each tail having one pos. and one neg. clip - all you have to do is hook one up to each side of the igniters. Doesn't matter at all which one is pos. and which is neg. - as long as current goes through (in whatever direction).

I suppose it goes back to the individual rocket/setup. If we are talking about a tight cluster of motors with all the igniter leads closely packed together, than yeah I see your point. But I would likely choose to not use the whip in that case anyway. But if we are talking about motors that are much more seperated (like with canted motors and a longish boat tail), well then the whip makes things a lot easier (to me anyway), and the whole pos./neg. thing doesn't even come into play.

Again though, to each his own. It's all good.

s6

 

[plano-doug]

And there really isn't all that much to go wrong with them - ensuring full continuity is no big deal. (snip)

If this was a 3 or 4 motor cluster, the chances of one of those little twists being faulty is MUCH higher than the solid, soldered connections of a well made whip.

- And if he is trying to make it easier, the whip would still win out. Again, in a 3-4 motor cluster, twisting extensions onto 6 or 8 igniter ends, and then twisting all those together (while "being careful" as he points out) is kind of a pain. Or you could just use those clips to hook it up in seconds.

Hi, S6,

The two biggest problems with a clip whip are clips shorting and clips coming off. I've seen too many cases where the clips, in a moderate cluster, are difficult to keep from touching each other - a little breeze can wreak havoc. Or, that same breeze can be a factor in one of the clips coming loose.

Using lead extensions, as Bob suggests, requires more effort pre-launch to build up the extensions, or requires purchasing ignitors with longer leads (ala Q2G2's). But either way, once those ignitors are all installed and the leads are twisted into two sets, pos and neg, then I either have full continuity or no continuity, but there is no in-between.

If a clip is clamped on one of the twists, those wires are all in good contact with each other - they all get the same voltage.

Conversely, thru 4 different alligator clips, I might see four different resistances and hence four different current flows.

A twist-up of four (or 7 or 10) freshly stripped wires will be much more reliable than four (or 7 or 10) clips which have been oxidizing in the bottom of your range box for the past 6 months.

Re: solder: The problem with the twists versus the clips isn't in the clips' solder connections; it's in the clip's conductivity to the wire it's clamped to. The connections of all those clips to all those wires is much less reliable than having two clips, pos and neg, attached to two twists of wires.

Re: pain: The pain involved in setting up such a cluster connection is still way less than the pain of crashing your rocket when 3 out of 6 don't light and it does a gravity turn power prang on the range in front of 100 other fliers

Doug

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