cluster question? Clone Estes ranger

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shoprobav

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Hello all.
I am thinking of building a clone of the old estes ranger cluster rocket.
A screamin mimi rocket contains just about all the parts one would need for this rocket.
I need to know what is the proper way to light all 3 engines correctly.
I have done searches on this forum and they all get way to complex.
Can i just twist the igniters together in the right pattern?
What size battery should i use?
i plan on using 3 C6-7 engines. Do they all need to have the ejection charge or will 1 be enough?
Will 3 ejection charges be too much for the body tube?
how do i ensure they will all light at the same time?
I know it's alot of questions but any help would be graetly appreaciated.
 

sandman

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Hold the bus a second!!

A Screaming Mimi has all the parts needed to clone a Der Red Max!

A Big Bertha is what you want to clone an Astron Ranger.

You will need a "Clip Whip" to light a 3 engine cluster. It's three wires soldered together at one end and an aligator clip on each of the other ends.

You connect you launch control clip the the connection of all three wires on the clip and the othwer launcher lead to the set of igniter wires twisted together.

You will need at least 12v to fire all three motors at once.

sandman
 

Karl

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Quickmatch (fuse) allways works for me , dont know if it's legal over there though. 3 same legnths of it shoved inside all 3nozles , and the ends twisted together with a ignitor taped to the end.
-Karl
 

mikeyd

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Here is a link to a PDF of the Estes TR-6 report on clustering. This will explain what you need for this, particually on page 3 and 4, as pertains to the hook up to the igniters, and the needs of the launch system. I recommend reading it, then if you still have questions come back, and some one here can answer then for you.:)

https://www.dars.org/jimz/manuals/tr-6.pdf
This is on the JimZ site which is full of lots of stuff to drool over.:D
https://www.dars.org/jimz/rp00.htm
 

Micromeister

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Shoppro:
I've been clustering BP motors most of my MR life.
The short answer is sure you can just twist one lead from each igniter into 2 bundles hook up you micro clips and push the button. sometime it will work, some times it will not.

Year of experience has proven that a 12volt Hi Amp/hr battery used with a relay ignition system is not A way to successfully, consistantly launch clustered model rockets.. It is the ONLY consistantly successful way! Are there other ways...Sure but unless you want an occasional motor(s) failing to ignite don't use them..
For 3 & 4 motor clusters I'd recommend any good Gel-cell battery in the 7 to 27amp/hr range. Try to maintain 2 battery crank amps (amp/hr) for each motor in your cluster, so that 7 amp/hr battery is really only recommended for 2 and 3 motor clusters.
Buy or build an Igniter tester. This is VERY important!, just because you just removed an igniter from the package does not mean its good!
Igniter installation is also important, I highly recommend rechecking the ignitors for continutiy after installation in the motors. I can't tell you how many times i've broken an igniter during the installtion process and would not have known until after the flight.
Build your clip whips with at least 16gage copper wire limiting the length to 18" or less.
I'll attach the way I have been wiring successful clusters for many many years, there are other ways but I can't claim 98 or 99 percent ignition success rate on any other then the wiring shown, using the procedure I outlined breifly above and encourage you to read my Tech-Tip-006 "BP motor Clustering" in the library section of Narhams.org for further explanations and examples.
Clustering is a lot of fun and ever exciting when done correctly, it isn't fun to crash a new model or have one flopping around the field when done badly.
good luck, OBTW a big bertha model Is a Ranger waiting to be clustered;)
Hope this helps if you need more help, please feel free to ask.
 

Micromeister

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heres the wiring diagram for a pocket igniter tester.
 
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