electronics HELP! for mass effect M8 assault rifle prop

[joshslayton]

Im making a replica M8 avenger assault rifle from mass effect and i wanted to make it like up. Basically i wanted to have leds in the barrel and in the side of the gun and i wanted to be able to turn off and on with a switch and also wanted to add a push button to put behind the trigger when pushed to add the muzzle flash in the barrel

Now i thought i had an idea on how to make it but i cam up with a problem. I made 2 sets one set to light up the side and to light up the barrel and add the effect with the muzzle flash

this light up the side

this lights up the barrel

Set number has a 9v battery clip soldered to a on/off switch and then soldered to some leds
But the problem i cam with is when the switch is off the 9v battery tends to heat up to a point were i cant touch it. I thought added another battery clip would fix it but they still heat up

Now for set number 2 has the same problem an is the same as set number 1 but has a push button soldered to it

So i have no idea how to fix the problem so id like to get some opinions and some help with this

Thanks.

 

[TotalForge]

First electronics project? The battery could be heating up due to a short circuit - if something is not connected right, current could flow back into the battery. the simplest example of a short is a wire going from the positive to the negative battery terminal - it's a bad thing, don't do that! If you have a multi-meter or continuity tester you can test each connection for a short, and fix it. Next, many LED's require a very tiny current - a full 9 volts into them can destroy them immediately. This is usually handled by putting a resistor on the positive lead, and if my fuzzy memory is right, one LED lead is longer than the other, and that's the one that gets the resistor - and the power. I could be wrong on that one, do a little Googling, visit the site of the vendor that made or sold you the LED's, and find out. You might ask in another electronics thread here, and do some internet searching on what value resistors to use, and preparing LED circuits in general.

 

[joshslayton]

First electronics project? The battery could be heating up due to a short circuit - if something is not connected right, current could flow back into the battery. the simplest example of a short is a wire going from the positive to the negative battery terminal - it's a bad thing, don't do that! If you have a multi-meter or continuity tester you can test each connection for a short, and fix it. Next, many LED's require a very tiny current - a full 9 volts into them can destroy them immediately. This is usually handled by putting a resistor on the positive lead, and if my fuzzy memory is right, one LED lead is longer than the other, and that's the one that gets the resistor - and the power. I could be wrong on that one, do a little Googling, visit the site of the vendor that made or sold you the LED's, and find out. You might ask in another electronics thread here, and do some internet searching on what value resistors to use, and preparing LED circuits in general.

Im deffinalty a beginner. The leds are pre wired leds i got from ebay i got them a while back so i cant remeber what kind of resistors are connected. And could you explain more on the wire being connect to the wrong terminal?

 

[sycor]

It looks like you soldered the red and black wires to the on/off switch. If I'm not mistaken you should just have either the red or the black going through the switch. I did something like this a few years ago and I'm pretty sure that corrected the battery warming up.

 

[vixr]

It looks like you soldered the red and black wires to the on/off switch. If I'm not mistaken you should just have either the red or the black going through the switch. I did something like this a few years ago and I'm pretty sure that corrected the battery warming up.

^^^this... I could draw you a simple diagram if you need it...

 

[joshslayton]

^^^this... I could draw you a simple diagram if you need it...

Can you do that? That would be cery helpful

 

[vixr]

joshslayton,
as you can see, the black wires from the battery connect directly to the LED ground wires...the red (switched) wires from the battery go to to their respective switches, and out from the switches to the LEDs. If the Rocker switch has more than two solder lugs, you only need to use two... see the switch in your diagram oriented longways up. Add as many LEDs at the point indicated in the diagram as you need. If the LEDs are not as bright as you would like for the muzzle flash we can tweak the configuration a bit if you dont mind changing the resistors... If you dont want to light the gun LEDS (stealth mode) but have the muzzle flash, wire it the way I drew the left diagram...If you want the rocker to control the micro switch too, just move the micro switch feed wire from the center of the rocker to the upper solder lug, use the diagram on the right, then the muzzle wont light unless the rocker is in the ON position. BTW, I found a greeting card sound module on ebay that allows you to record a bit of audio that may be useful if you wanted to add audio...

 

[vidman]

josh,

I noticed you stated that your leds are prewired with a resistor, if they are for automotive use then the resistor is to high for your use it is a 470 ohm(12volt) and you only need a 270 ohm for 9 volts

here are a couple of sites that can help you with your resistor problems and can help you design your circuits;

LED series parallel array wizard

LED Series Resistor Calculator

good luck

 

[joshslayton]

joshslayton,
as you can see, the black wires from the battery connect directly to the LED ground wires...the red (switched) wires from the battery go to to their respective switches, and out from the switches to the LEDs. If the Rocker switch has more than two solder lugs, you only need to use two... see the switch in your diagram oriented longways up. Add as many LEDs at the point indicated in the diagram as you need. If the LEDs are not as bright as you would like for the muzzle flash we can tweak the configuration a bit if you dont mind changing the resistors... If you dont want to light the gun LEDS (stealth mode) but have the muzzle flash, wire it the way I drew the left diagram...If you want the rocker to control the micro switch too, just move the micro switch feed wire from the center of the rocker to the upper solder lug, use the diagram on the right, then the muzzle wont light unless the rocker is in the ON position. BTW, I found a greeting card sound module on ebay that allows you to record a bit of audio that may be useful if you wanted to add audio...

View attachment 241675 View attachment 241683

Thanks man that help me alot and about the sound module would it be able to solder a push button so that when the trigger is pushed it make the muzzle sound from the game

 

[vixr]

Thanks man that help me alot and about the sound module would it be able to solder a push button so that when the trigger is pushed it make the muzzle sound from the game

Josh, That ebay store had some push button types too...