How to properly ignite a 3 motor cluster

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Donaldsrockets

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Since I plan to fly my Richter Recker in the near future, I need to know how to properly wire up three igniters together to insure reliable motor ignition. I've suceessfully launched two motor birds including a Deuce's Wild but this is my first three motor bird.

Motors used will be either 3X D12-5 or 3X E9-6

I would appreciate any help you can provide as I would really like this to go off without a hitch.
 
I use a clip whip from Thrustline Aerospace. Haven't had a problem yet.

bmhiii
 
Don, I'm surprised that some information about launching clusters did not come with kit. When I ordered my Deuce, I got the information. Contact Fliskits.
 
Didn't your RR come with clustering techniques? I know Jim was sending that out with a lot of his multi-engine rocket kits...

WW
 
Thanks for the responses guys. I did get the clustering techniques sheet and I did read it but I was still a little unclear. I'm highly thinking about getting a clip whip because our clubs leads only have two clips each.

bmhiii, how much did that clip whip cost?
 
Donald,

If you don't have time to get one through the mail, you can make one with parts from Radio Shack. Took me about an hour to make a 5-head whip... It didn't look purty, but it's worked well! Fired off a deuce and a tres simultaneously, too!

WW
 
Originally posted by Donaldsrockets
Thanks for the responses guys. I did get the clustering techniques sheet and I did read it but I was still a little unclear. I'm highly thinking about getting a clip whip because our clubs leads only have two clips each.

bmhiii, how much did that clip whip cost?

Clipwhips will certainly make hookup easier. The main points you want to consider when doing clusters (of any reasonable size) are:

0) (#0 cuz i forgot this one and didn't want to renumber...) put a small chunk of wadding in the TOP (ejection end) end of each motor and tape in place. This will prevent reverse ignition of the motor should it fail to ignite at launch.

1) Use matched ignitors (look through your stash of ignitors and select 3 that match in physical size (same amount of pyro on them))

2) Grasp each ignitor by the tip and *gently* spread the leads a little bit. This is a common place for shorts.

3) Be extra careful when installing them to be sure that the tip of the ignitor is touching the propellent

4) Use the provided ignitor cap or a small ball of recovery wadding to secure the ignitor in place (do NOT simply tape it down - i've seen this done countless times and it almost always causes a failure)

5) With the Richter Recker you can twist the leads if you are careful not to short them out. A clip whip makes things much easier

6) Make sure you have a suitable power source (car battery recommended)

7) clean yer micro clips befor attaching!

hope this helps! good luck!
jim
 
Donald,

Hospital_Rockets gave you the Thrustline link, that's where I got mine and I think the prices are still the same. I've got both the 2 and 3 end clip whip. They are well made using solder to make better connections and heat shrink tubing to hold it all together. I would think they are easy to make and if you already have the solder set-up, they would be quite inexpensive. However, if you're a litttle on the lazy side like me, Thrustline is an excellent choice.

Jim had all the right suggestions also. High on the list is a launch controller with enough juice to light a cluster.

One last comment. Clustering is highly addictive!!!:D

Have a blast!!!!

bmhiii
 
Yeah, no kidding. I've already got an OOP Estes Pro Impulse that I've launched successfully twice and I also have a Deuce's Wild, that rocket in particular is addictive, I think we know who to thank for that:D and I plan to get a Tres in the very near future and I hope to one day bash an Estes Big Daddy into a quad 18mm.
 
Originally posted by jflis
5) With the Richter Recker you can twist the leads if you are careful not to short them out. A clip whip makes things much easier
[/B]

For more reliability you could solder the leads together (before installing them into the motor!) instead of twisting them, then you don't need a clip whip.

Bruce S. Levison, NAR #69055
 
I wouldn't think so. I have however decided that I am going to order a clip whip from Thrustline this week. Since my next club launch isn't until May 15, I think I have enough time to order it and get it here before then.

Thanks again for all the great tips guys.
 
PM John Rowan-Stern (Flying-Siilverad). He owns Thrustline and has the unsavory tradition of taking care of TRD-ers.
 
Donald,
You have received some good tips so far. I built a Boostered FAT BOY with 3 - 24 mm mmts in each stage. Staging part was easy but the booster ignition was a fun experiment since it was my first.

Clip whip... you can make one from radio shack parts and a chunk of extention cord or suitable speaker wire. The main lead that connects to the pad power splits in a Parallel circuit to the motors. You can have as many motor whips as you want to add. Just make sure that you have a positive connection at each clip to insure ignition.

I use the Estes ignitors that come with the motors and they work great. Just check them and make sure that they have all the pyrogen still. Older ones... sometimes the stuff cracks off with rough handling.
Normal club pad power is 12 volts and that has always worked for me.

Next thought... you could use a strong case of safety,caution,pay attention: I take a drill bit just smaller than the nozzle size. With leather gloves on I work the drill (plastic or brass--I used a steel bit very carefully) bit around for a little while to create a fresh surface in the propellant. There will be some powder generated by this. Leave it there. I insert the Estes ignitor and push wadding (a goodly amount)down into the nozzle around the ignitor with a tooth pick or other similar small thing to keep the ignitor where I put it next to the propellant. Then carefully bend over the ignitor to the outside of the airframe. Attach the clip whip and watch it go.

Sometimes when they drill out the nozzle at the factory some of the clay dust gets down into the hole and it sort of glazes over on top of the propellant. Using the drill bit to gently scratch that glazing way surely helps with the clip whip and the fact that you spend some diligence to make sure the ignitor stays next to the propellant where it will do the most good.

You can see the FAT BOY on my web site. Well a picture of it anyway. If you want more info on it then just send a private note to me and I can go into it further with you. Also, I can send you some pictures. I had them on the website but my club is working on a mega cluster of Estes motors and cleared the project page for that. Still under construction but it is coming along.


Bill
"Stop Looking for a Mentor, and BE ONE."
 
The Estes ignitor leads are long enough so you don't really need a heat sink on them when you solder them together; provided you work quickly. However, the pyrogen can melt and eventually ignite if it gets to hot. I typically use a heat sink on the leads. I grip the leads with a needle nose pliers behind the pyrogen while I solder them together.

Bruce S. Levison, NAR #69055
 
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