Anyone have experience with model rockets?

[92saturnsl2]

I bought an Estes model rocket for one of my sons that has tandem engines. I later read in the instructions that it requires a beefier launch controller (their upgraded one) that takes six 1.5V cells instead of 4. I have the original 4-cell launch controller for our smaller rockets. I'm not paying $40 for a larger launch controller for this one rocket when I'm fairly certain they're just creating a short circuit at the igniter(s). I assume they want six cells (9V) to ensure enough power for both igniters.

The product manual for the larger launch controller mentions you can also power it with 8-10 NiMh cells (9.6-12V) or 3 Li-Ion batteries (approx 11.1V).

Am I correct in assuming I just need to create a short circuit? Anything wrong with alligator clips (with enough length for safety of course) and a 12V lead acid battery? From what I can tell, the igniters just have a small filament that burns off when enough power is applied.

 

[vw7674]

True. They used to make use of 6V lantern batteries back in the day.... A 12V automotive battery should do it. Fine gauge Nichrome wire is the short/heat producer onto that droplet of black combustive stuff...... Happy Travels!

 

[kschachn]

I've flown model rockets for about 50 years, both casually and in competition. The thing you want with clusters is for the igniters to fire all at the same time. That's why you need a larger battery to make sure there isn't a delay in one or more of the engines igniting.

As you mention you can make your own controller if you're so inclined. They aren't all that complicated and you can use any battery you want for the power source. The reason for the incandescent lamp in the circuit is for a continuity check, the lamp is then short circuited and this ignites the engines.

 

[JimPghPA]

You need the higher Voltage with the ability to supply enough current so that you insure every igniter ignites fast. If you over-loaded a lower power ( original ) launce controller, then there is a good chance one engine would have its igniter fire before the others. If one fires ahead of the other(s) then it will launch the rocket and the other(s) will have their igniter fall out before they are lit.

A 12 Volt wet cell like a motorcycle or car battery will have plenty of enough power to ignite all the engines fast enough so they all work.

Thicker wires from the battery to the launch pad would also be a good idea.

BE SURE TO WIRE THE ADDITIONAL ALLIGATOR CLIPS IN PARALEL. THIS IS VERY IMPORTANT.

If you wire the additional alligator clips in series then when one ignitor burns open, it will interrupt power to others.

 

[kschachn]

This is ancient now (originally 1963) but back in the golden days of rocketry Estes Industries published a bunch of technical reports on various aspects of model rocketry. Check out the one on clustering techniques, most of what's in the publication is still applicable today.

https://estesrockets.com/wp-content/uploads/Educator/2845_Classic_Collection_TR-TN.pdf

 

[Passport1]

Yes, I used to build them when my kids were young. We'd go to the school fields on the weekends and shoot them off. Estes models, still have one around with the launcher. They would gain ~600-1200' altitude. Steamers recovery for most but a few more sophisticated had parachutes. One of my more adventurous friends built one with a payload compartment and put a mouse in it.

Didn't work out well for the rodent astronaut.

 

[wag123]

A 12v car/motorcycle battery works great. So does a 12v gel cell battery.

 

[aquariuscsm]

We used to play around with those in the 70s. I had no idea they were still around

 

[Wheel]

We always used the car battery. We'd made our own launch cables with alligator clips and a pushbutton tied into the car that brought us. Later we used 12volts from security light batteries and made a countdown box with led display and a 555 chip. We were all nerds

 

[wings&wheels]

Great memories of Dad and I with them. Enjoy!

 

[eljefino]

The battery from a cordless drill works great too.

 

[92saturnsl2]

This is ancient now (originally 1963) but back in the golden days of rocketry Estes Industries published a bunch of technical reports on various aspects of model rocketry. Check out the one on clustering techniques, most of what's in the publication is still applicable today.

https://estesrockets.com/wp-content/uploads/Educator/2845_Classic_Collection_TR-TN.pdf

Thanks for that! The document states each igniter should have about 5 amp. That seems high, but it will help me size the wire appropriately.

 

[Donald]

Thanks for that! The document states each igniter should have about 5 amp. That seems high, but it will help me size the wire appropriately.

With 00 gauge welding cable you will have no voltage drop and can easily handle 5 amps. Happy blast-off. Might be slightly overkill however.

 

[Kruse]

I realize that this was decades ago, but when I built and shot my Estes rockets, I just used large fireworks fuse to ignite them. I never did use a battery igniter. I guess I was too poor to use that high-tech gizmo.

 

[Gimpy1]

Growing up in DFW (Plano) as a latch key kid in the 80's and 90's, I had empty fields everywhere, which was perfect for model rockets. I started with Estes kits then started leaning more about rockets and started designing and building my own. Then I got into R/C stuff. It was a great time. Oh building your own launch box is very easy, I used a 12V sealed motorcycle battery and it had plenty of power to fire 4 engine clusters

 

[Astro14]

Built and launched so many when I was younger. Still have some of them as mementos, including the Black Brant III, which I built after seeing the Black Brant in a museum in Winnipeg.

Still have the launch "kit" that I built from a wooden box that had housed beginner woodworking tools. It was re-purposed. In that box is a older controller that used a 6 V lantern battery. It was enough to fire the 4 C6-3 engines on my Saturn 1B.

A 6 volt lantern battery should provide the current needed to fire both igniters on your rocket simultaneously. Igniters need to be powered in parallel. You can twist the igniter leads together to create that parallel circuit.