Author Topic: I have wired the circuit properly, it just won't ignite on the other end!! (Read 3729 times)

cuesoccer24 · « **on:** March 24, 2020, 06:07:51 pm »

Hello to all,
I am trying to build a model rocket launch controller using the shell of an old N64 controller. One guy did it on youtube and I am trying to replicate exactly what he did. I wanted a DIY project since we are staying home from work with the virus out there. I am a beginner with electronics and I just need help wiring this together. I thought I completed the circuit yesterday and when I went to connect the two 9V batteries, nothing happened. There was no connection to the mini push button switch or from the bigger red push button to send power to the mini LED. Not sure where I went wrong, but if someone can help me figure this out/help me wire things together I would be greatly appreciative. The two pictures I have attached are what I am working with. One picture is of the shell of the N64 controller with the parts inside and where they all go. The other is the diagram/schematic of the wiring that I need to complete, I just can't figure out how. Thanks for any info or diagram help.

bob91343 · « **Reply #1 on:** March 24, 2020, 07:31:30 pm »

It's not clear what you want to do. Please explain what function you want and which button is supposed to do what.

You have connected the batteries in parallel so you still have 9 Volts. It goes through the first button to supply 9V to the second button. When you press the first button, the LED will light unless you install it backwards. While holding the first button, you press the second and the full 9V goes to the igniter. So you need two hands to press both at once, the way you have drawn it.

cuesoccer24 · « **Reply #2 on:** March 24, 2020, 08:01:53 pm »

First of all, thank you for replying to my thread, I really do appreciate your time. Sorry if I wasn't really clear with my post. I wasn't sure of how to really word it since I am a beginner with this stuff.

There are 2 functions I would like to have happen.

When I would press the big red button on the top of the controller first, this would send the signal to the LED to light up to show I have contact and ready the system. The second button (bottom...gray Z button-mini push button installed inside the controller) would then be triggered to send the signal out to the igniter to light the rocket engine.

The big red button opens the circuit and the bottom Z button would close the circuit and send the signal to the igniter?

I hope that clears anything up. Explaining it is hard but I tried my best. I included two more pictures.

senso · « **Reply #3 on:** March 24, 2020, 08:56:25 pm »

In your original image where it says to igniter, you add the second button, interrupting the signal that already comes from the first button.

cuesoccer24 · « **Reply #4 on:** March 24, 2020, 09:52:33 pm »

Senso...could you explain further? maybe help me with a drawing of the diagram if mine sucks?

krappleby · « **Reply #5 on:** March 24, 2020, 10:10:26 pm »

HI,

from the 9v source to your first switch, Connect this to your resistor and led, Run a wire from here to your - on the battery, (when you press first switch the light will come on but no signal to ignitor)
then connect another wire from the resistor (- end) to your second switch, run that directly to your igniter. (when pressed (only if first switch is active and led on, will signal be sent to the ignitor)

hope that explains it a little better..

Cheers

cuesoccer24 · « **Reply #6 on:** March 24, 2020, 11:08:37 pm »

I appreciate the feedback, I will try that shortly.

cuesoccer24 · « **Reply #7 on:** March 25, 2020, 03:55:40 am »

I figured it out, thanks everyone for your contribution!!

bunnyThief · « **Reply #8 on:** March 25, 2020, 04:07:39 am »

Did you mix up the terminals on the batteries?

cuesoccer24 · « **Reply #9 on:** March 25, 2020, 04:15:17 pm »

nope, didn't mix them up, just wasn't running the correct wires to certain parts. I was able to connect everything including both switches. I can now open and close the circuit. It is an accomplishment for being a noob with electronics!!

cuesoccer24 · « **Reply #10 on:** March 28, 2020, 01:54:06 am »

So everything is connected and wired properly. I just have one question...why won't everything produce enough electricity to heat the igniter? My batteries are good. I am stumped.

bunnyThief · « **Reply #11 on:** March 28, 2020, 02:13:52 am »

Quote from: cuesoccer24 on March 25, 2020, 04:15:17 pm

I was able to connect everything including both switches. I can now open and close the circuit.

How are you checking that the circuit is closing?

bob91343 · « **Reply #12 on:** March 28, 2020, 02:30:37 am »

What are the igniter specifications? Two puny 9V batteries might not be able to supply the required current.

Nerull · « **Reply #13 on:** March 28, 2020, 02:33:08 am »

Estes-style igniters are notoriously high current - I've seen all-fire figures of around 2A, it often takes several seconds for them to ignite with disposable battery powered launch systems, and typical club systems use car batteries. Thin gauge wires can also be a problem.

Connect the clips to a light bulb and make sure its working at all.

Pretty much every other manufacturer uses e-matches that fire at much lower currents, there have been issues with the continuity check function of launch systems built for estes igniters accidentally setting e-matches off.

Stray Electron · « **Reply #14 on:** March 28, 2020, 02:49:35 am »

Quote from: bob91343 on March 28, 2020, 02:30:37 am

What are the igniter specifications? Two puny 9V batteries might not be able to supply the required current.

Absolutely this. I used to use a 12v car battery and even that wouldn't have enough power to ignite them if I used a long run of wire. I would use something like three 18650 Lithium batteries in series. They can put out a tremendous amount of current for a short time. Also I found that if I dropped two or three grains (pieces not weight) of 2F or 3F Black powder into the nozzle before installing the igniter that that gave me much better ignition. I used a small tuft of cotton loosely pressed into the nozzle to hold the powder and igniter in place.

PS also you need to make sure that you're using GOOD switches. The junk sold by Radio Shack and the cheapo switches that just push a copper plate against a wire aren't good enough. Go get a couple of real military surplus switches or some good industrial switches.

MarkF · « **Reply #15 on:** March 28, 2020, 02:50:35 am »

Wire gauge and wire length...
You may have too much voltage drop in the wire.

Consider dividing it into two pieces:

cuesoccer24 · « **Reply #16 on:** March 28, 2020, 04:13:34 am »

Hello to all,

First of all, thank you for your advice and replying to my thread.

I'll try to answer as much as I can.

bunnyThief: I am not sure how to check for a closed circuit. All I know is that when I push the big red button, this allows me to push the 2nd button (trigger button on bottom of controller) and this lights up the LED. If I were to press the big red button again and then push the trigger button on the bottom, the LED will not light up. Is that what it means when the circuit is opened and closed?

Quote from: bob91343 on March 28, 2020, 02:30:37 am

What are the igniter specifications? Two puny 9V batteries might not be able to supply the required current.

The igniters are estes model rocket igniters. not the most quality built things in the world but its what I had. I am trying to use two 9v but I guess that isn't cutting it.

Quote from: Nerull on March 28, 2020, 02:33:08 am

Estes-style igniters are notoriously high current - I've seen all-fire figures of around 2A, it often takes several seconds for them to ignite with disposable battery powered launch systems, and typical club systems use car batteries. Thin gauge wires can also be a problem.

Connect the clips to a light bulb and make sure its working at all.

Pretty much every other manufacturer uses e-matches that fire at much lower currents, there have been issues with the continuity check function of launch systems built for estes igniters accidentally setting e-matches off.

How do I connect to a light bulb? Just touch the wires on the base? sorry if that's a dumb question.

Quote from: Stray Electron on March 28, 2020, 02:49:35 am

Quote from: bob91343 on March 28, 2020, 02:30:37 am
What are the igniter specifications? Two puny 9V batteries might not be able to supply the required current.

Absolutely this. I used to use a 12v car battery and even that wouldn't have enough power to ignite them if I used a long run of wire. I would use something like three 18650 Lithium batteries in series. They can put out a tremendous amount of current for a short time. Also I found that if I dropped two or three grains (pieces not weight) of 2F or 3F Black powder into the nozzle before installing the igniter that that gave me much better ignition. I used a small tuft of cotton loosely pressed into the nozzle to hold the powder and igniter in place.

PS also you need to make sure that you're using GOOD switches. The junk sold by Radio Shack and the cheapo switches that just push a copper plate against a wire aren't good enough. Go get a couple of real military surplus switches or some good industrial switches.

Are those lithium batteries readily available and not too expensive? Thanks for the info. I am using good switches...they seem to work and my LED light turns on.

MarkF: Thanks for the diagram...to be honest I am not totally sure how to read it but I will try to figure it out. I am a newbie with electronics.

Alex Eisenhut · « **Reply #17 on:** March 28, 2020, 05:35:08 am »

Brings back memories. Too much current can make the wire explode apart never igniting the little black blob.
Basically the system works in two levels, there's a continuity check which lights up a LED/bulb in series with the igniter. If that doesn't light up, there's a problem.
Typically after a few launches the clips to the igniter get dirty.
AFAIK the igniters are rated for 6V and they rely on the resistance of the long wire to the controller to limit the current.
I didn't know model rocketry was still a "thing". When I was doing it people thought nothing of two weird kids with rockets and batteries taking public transit.

What kind of rockets are you building? Do they still have the Estes designer's kit?

cuesoccer24 · « **Reply #18 on:** March 28, 2020, 05:55:44 am »

Just regular model rockets from estes...just a build I wanted to do since I am not working right now. These are just simple put them together kits. I haven't had any wires "explode". At this point I kind of wish they would explode to ignite the rocket engines!!

krayvonk · « **Reply #19 on:** March 28, 2020, 07:12:55 am »

I bet that circuit is right, its just i dont understand why that resistor and led is there, i know its got 500 ohms resistance, but wouldnt that sorta ignite it as well, especially if you put too many batteries in I mean.

MarkF · « **Reply #20 on:** March 28, 2020, 09:26:20 am »

In your first photo, it looks like you are using thin speaker wire.

I did a quick look around the web on model rocket igniters and they need a lot of current for a short period of time.
At the very MINIMUM, I would use 16AWG/2 Lamp Cord.

An alternative battery option might be a small 12V motorcycle lead acid battery.

Note. I modified my previous circuit with detailed part names (plus a few mods)...

Quote from: krayvonk on March 28, 2020, 07:12:55 am

I bet that circuit is right, its just i dont understand why that resistor and led is there, i know its got 500 ohms resistance, but wouldnt that sorta ignite it as well, especially if you put too many batteries in I mean.

The resistor/LED are there to indicate continuity from the battery through the igniter when the system is armed.
From what little I have read, you should be able to safely have less then 100mA current through the igniter without it going off. A typical LED is less than 20mA.

MarkF · « **Reply #21 on:** March 28, 2020, 09:58:38 am »

Single battery (with higher capacity) option:

Lots of ways to skin a cat here. Biggest concern is the safety interlocks!

cuesoccer24 · « **Reply #22 on:** March 28, 2020, 03:03:32 pm »

I think I am starting to understand this diagram a little better Mark, thank you for labeling everything.

I am using speaker wire and I think it is 10 AWG...would that possibly be the problem with not getting enough current to the igniters?

cuesoccer24 · « **Reply #23 on:** March 28, 2020, 03:06:32 pm »

Hopefully this clarifies anything...I am going to open up the controller in a little bit to show the inside wiring diagram and see what everyone thinks.

cuesoccer24 · « **Reply #24 on:** March 28, 2020, 04:42:17 pm »

Does my wiring make sense?


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Author Topic: I have wired the circuit properly, it just won't ignite on the other end!! (Read 3729 times)

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