Making prop for movie and not sure what i need

Discussion in 'General Electronics Chat' started by Fallout Studios, Nov 5, 2011.

  1. Fallout Studios

    Thread Starter New Member

    Nov 5, 2011
    3
    0
    Hi All, New to the board, and new to electronics. I have done the basic make an LED light on a bread board, no real hardship there but here's what i'm after:

    I have a prop gun (a 9mm 45. pistol) Its an airsoft pistol i've modded to look real.

    Long and short i would like to have an LED inside the gun just underneath the chamber. Now i would like to use 10mm High Bright LED. I have it working off of 4 AAA batteries. I plan to use the original Battery plug in the gun as the power source hence the 4 AAA instead of a 9 volt.

    I am using an 150 OHM resistor in sequence with the LED and it works perfectly.

    The problem i'm running into is i need it to "Ease on" when a small button is pressed. now the button cannot be held either it needs to be pushed and ease on it self and stay on untl the button is pushed again.

    It also needs to fit in the gun so the smaller the better.

    I am a newbie so good break downs would be helpful.

    Thank you in advance.


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    Last edited by a moderator: Nov 5, 2011
  2. Wendy

    Moderator

    Mar 24, 2008
    20,766
    2,536
    Here is a simple 555 circuit that will work. Push once for one, push once for off...

    555 Bistable Multivibrator

    A good button is called a tactile switch, it is small and cheap, and has a nice "click" when it makes contact.

    http://www.bgmicro.com/search.aspx?find=tact+switch

    http://www.bgmicro.com/search.aspx?find=tactile+switch

    It is possible to make this extra small by using what is known as surface mount, or SMT. If you go this route you will need to make a home brew PCB, but you could easily get it under 1" X 1".

    I also have a blog article showing a lot of special effects with LEDs, more of a tutorial really...

    LEDs, 555s, Flashers, and Light Chasers

    There is another gadget that can also do special effects with an LED. It is called a microcontroller (or µC), which includes popular makes such as PIC, Arduino, Axe, ...

    Basically these chips can literally be programmed, which eliminates a lot of extra circuitry and makes for small packages.
     
  3. SgtWookie

    Expert

    Jul 17, 2007
    22,182
    1,728
    Now you have me curious - what model number did you purchase?
    Airsoft toys fire 6mm plastic balls.
    9mm Luger/NATO and .45 ACP are both rounds for semiautomatic pistols and rifles.
    The current USA service pistol is the Beretta M9; the civilian equivalent is the 92FS, both chambered in 9mm NATO.
    The previous USA service pistol was the Colt M1911A1 chambered in .45 ACP.

    There are lasers available for the M1911 and derivatives that replace the recoil spring plug, the round crosshatched item just below the muzzle.

    I can only surmise that you're trying to mimic the appearance of an incandescent light. Is that the case?

    This doesn't quite make sense; as it would have to be in the magazine area. Unless that's what you mean?

    If they fit in the magazine area, you're golden.

    That's "in series". Just FYI. ;)

    By "ease on", I assume you mean that you want it to gradually increase in intensity. How long should it take to go from dark to fully on?

    Circuits can be made fairly compact.

    Some clarifications so that we know what we're dealing with would be helpful.
     
  4. Wendy

    Moderator

    Mar 24, 2008
    20,766
    2,536
    You will probably need to find a local tech expert from what I'm hearing. What is your location?

    You will notice most of the old hands here have their City/State in their profile. It is for parts houses and situations like this.
     
  5. Fallout Studios

    Thread Starter New Member

    Nov 5, 2011
    3
    0
    Hey Guys thanks for responding:

    I say 9mm .45 because that's the gun its replicating in its "look". I've never even loaded plastic balls into any of the airsoft guns i bought, usually have to age them and make them look worn for "effect" on screen.

    As far as the LED being underneath the chamber that's exactly what i mean. for the project i'm working on, the desired look is a modern day pistol with a futuristic feel to it. The guts of the gun have been removed since i do not need the gun to operate and the chamber has been hollowed out to accommodate an acrylic tube that has been slide into the barrel. Inside the silver tube is a metallic liquid looking like mercury. I would like the LED to sit underneath that acrylic tube (which is visable from the chamber) so that when they pull the slide back they can push a tiny button and the LED will heat up likethe gun is some sort of bio-mechanical weapon. I know it sounds crazy but the project has a bit of SCI to it. I can add pictures if it would help.

    The battery pack that came with the gun is located in the magazine area so i felt it would be easiest if i used that as my power source. As stated above i removed all other guts of the gun to accomodate the 10mm LED just underneath where i want it sit.

    "In Series" haha yes in sequence is my editor speak. thank you!!

    yes by "ease on" i want it to go from off gradually probably over 3-4 seconds i'm not exactly sure yet. would this be referred to as oscillating?

    Thanks bill, i updated my profile a little while ago to have this information available.

    Thanks guys. I'm interesting in so info like its referred to as "in series" is helpful.
     
  6. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
    6,357
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    Photo of what you have so far, and a photoshop or two of what the concept finished product should appear like would help. You could use the area behind the chamber, where the hammer/firing pin reside on a standard handgun to place the electronics and LED, so the transparent/translucent cylinder would be lit up unobstructed. Maybe use the safety for the on switch.

    Please do not use the trigger for an on switch. People learn stupid stuff from movies, like walking around with their finger on the trigger. Finger off the trigger until sights are on a target you intend to destroy, and treat every gun (toy or not) as if it were real and loaded, unless excessively proven otherwise.
     
  7. Fallout Studios

    Thread Starter New Member

    Nov 5, 2011
    3
    0
    Hi guys took some photos i hope they help,

    the first photo is the gun (with some minor pieces still removed: trigger, grip)

    second photo highlights to areas:

    1. is the chamber where the clear tube will be visible and the LED would be underneath this (you'll see later on).

    2. is where i would like to place the switch to turn it on and off. i would like most of the switch to be inside the gun and just the switch sticking out. I think its called a tactile switch.

    Third photo is just a closer look at what in the chamber and what will be seen.

    fourth photo is just the inside of one side of the gun. you can see i removed most of the guts to make room for parts i would need to put in here.

    fifth photo highlights where the LED sits and the battery pack.

    last photo is the inside of the other side of the gun just so you can see the tube. I' sure it goes without saying that that the sticker on tube will be removed.

    Once again i hope this helps. thanks again guys.
     
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