Need a little help with wiring..

Discussion in 'Gun Building, Modifications & Repairs' started by Splode, Feb 5, 2018.

  1. Splode

    Splode Well-Known Member

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    Does anyone have experience with Aug platforms? I am am attempting to install a mosfet, but apparently AUGs aren't as straightforward as most guns due to the dual stage trigger. I wired everything like it is supposed to on a normal V3 gearbox and the trigger switch makes it fire full auto until the trigger is pressed far enough back to the trigger contacts. Then it stops.
    I'm assuming I have the trigger contacts wired wrong.
    Any help would be GREATLY appreciated.
    If requested, I can post a pic later of the way I have things wired now.
    Thanks
     
  2. Splode

    Splode Well-Known Member

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    It might.. It's hard to tell what's going on there. In using a microfet which is only wired on the positive wire.
     

  3. Lefse

    Lefse Well-Known Member Supporting Member

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    Mosfets are usually wired on the negative wire.
     
  4. Splode

    Splode Well-Known Member

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    Sorry. Meant negative. In any event, I think I have it wired properly as far as v3 gearboxes go because it shoots full auto faster than before and no sparks on the contacts. It's only when the trigger is back all the way to the contacts that the cut off gets tripped for some reason and it stops firing.
     
  5. Lefse

    Lefse Well-Known Member Supporting Member

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    Here's how I've wired my AUG:
    [​IMG]
    [​IMG]
    Disregard the lacking cut-off lever, this is a full-auto only DSG build, but the wiring will give semi-auto in the first trigger position with a cut-off lever.
     
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  6. Splode

    Splode Well-Known Member

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    Awesome. That should help a lot. A bit hard to see that black wire under where you wrote "battery+". What is that?

    On a side note. If I'm going to rewire this, then I need some softer wires. Got any links to some good wire?
     
  7. Lefse

    Lefse Well-Known Member Supporting Member

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    That's the wire that supplies power to the semi auto switch.

    Any rc store will have silicone wire in various gauges.
     
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  8. Splode

    Splode Well-Known Member

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    I'll have to swing by the hobby shop and grab some wire.
    What is that little black wire soldered to in the first pic? Is it soldered under that red wire on the right? and is the other end of it going to the front tab or the back tab of the trigger switch?
     
  9. Lefse

    Lefse Well-Known Member Supporting Member

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    It's connected to the positive battery wire and goes to one of the tabs on the semi auto switch.
     
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  10. Splode

    Splode Well-Known Member

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    Either/or? I mean, it doesnt matter which tab? I'd assume it doesnt huh cause the switch is just passing current from tab to tab.
    Here's the setup I followed off the microfet website. I wired the trigger contacts somewhere in between the motor and the trigger switch. Might explain why I blew a fuse at one point. Lucky I left that.

    Capture.PNG
     
    Last edited: Feb 5, 2018
  11. Lefse

    Lefse Well-Known Member Supporting Member

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    It doesn't matter on the semi auto switch but it does matter on the full auto switch.
     
  12. Splode

    Splode Well-Known Member

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    So stupid question. which Is the full auto switch? Cause mine currently is the one in the blue trigger mechanism. Not the one halfway up the grip.
     
  13. Lefse

    Lefse Well-Known Member Supporting Member

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    The switch inside the gearbox is for semi auto since it gets disengaged by the cut-off lever after one cycle. The switch on the trigger is the full auto switch since it only disengages when you let go of the trigger.

    For AUG's you need two pairs of trigger wires since it has two switches, while most AEG's have only one switch. The wire that goes to the positive terminal on the motor in the old wiring is basically the wire that goes to "gate" on the mosfet in the new wiring.
     
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  14. Splode

    Splode Well-Known Member

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    OK wow. Then I think I have something wired backwards. Because I can slowly pull the trigger until it shoots full auto. It works when the semi auto trigger switch is engaged. The full auto contacts do nothing. If I pull the trigger even slightly past that initial point, it allows the cut off to engage and it will stop firing or fire a single shot if done all at once.
    Here is how I wired things up. Kinda ignored the full auto switch. Does that explain why things are working the way they are?
    [​IMG][​IMG]
     
  15. Splode

    Splode Well-Known Member

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    Studied that pic of your gearbox and this is what I'm getting from it. Is this correct?[​IMG]
     
  16. Lefse

    Lefse Well-Known Member Supporting Member

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    Yeah, that looks right actually, this way one tab on each switch is connected directly to battery + and the electricity is switched back to gate on the mosfet.

    I can see what the problem is with your wiring, the blue gate wire should be connected to one of the tabs on the full auto trigger, in parallel with a wire from one of the tabs on the semi auto trigger. The way you wired it the electricity passes through the lower tab on the semi auto switch and "skips" the full auto trigger contacts.
     
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  17. Splode

    Splode Well-Known Member

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    Awesome. Thanks man. You're a great help. Not many people understand augs. I guess I'm lucky it worked the way it did and didn't fry something.
    Cheers! I'll let you know if it works.
     
  18. Protege240

    Protege240 New Member

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    I hate to ask this on an unrelated post but I can't for the life of me figure out how to make a new post! I am a new member, if that makes a difference. I am also EXTREMELY new to air soft and have a few questions I would like to ask in a thread of my own.
     
  19. Splode

    Splode Well-Known Member

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    Just choose the correct category for your question and look for the button that says post new thread. [​IMG]
     
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  20. Splode

    Splode Well-Known Member

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    So I can use thinner gauge wire like shown in blue in my highly artistic drawing?:D
     
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