Gear Box WTF

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Ground Robin
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Gear Box WTF

Post by Ground Robin » Mon Jul 14, 2014 3:35 pm

Hey guys! Been a long time, I know.
I'm kinda stuck on this gear box of mine.
It's a V.2 (it's for my g3) and it keeps locking up when the piston gets almost all the way back. I've tried different gears, different motors, different batteries, different springs, different pistons, yadda yadda pretty much different everything except gear box shell. I have it shimmed great. Without the spring in and testing the gears, they spin flawlessly and without resistance, but as soon as it engages the piston and starts to compress the spring, it is met suddenly with quite a bit of resistance. Enough to stop a M120 motor dead in it's tracks at the last few teeth of the gear. I have a spare gear box shell and I'm tempted to just throw stuff into that one to see if it's the wires or something else but I just can't figure it out. Any suggestions?
Currently, the only thing that isn't original JG parts are the m120 motor and 13:1 gear set.
And just for any more information, this gun used to shoot amazing.
I need it for Ripley!!! Help!!!
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Re: Gear Box WTF

Post by Tank » Tue Jul 15, 2014 11:29 am

Do you have both a spring guide with bearing and a piston head with bearing?
If so, with some springs it will cause exactly what you're describing. The spring will fully compress before the sector gear can release the piston, thus completely locking the gearbox.
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Re: Gear Box WTF

Post by neoM4tech » Mon Jul 28, 2014 12:54 am

If removing one bearing doesn't allow enough space (assuming you have one on the spring guide and one on the piston head) the next step is to short stroke the gears/piston by one tooth. This will drop the fps potential a little, but lower fps is better than a gun that isn't firing at all. IF you decide to ss remember to take the first tooth off the sector and the last tooth off the piston. preferably still leaving a metal release tooth on said piston. This is a last resort ONLY if nothing else works as it cannot be undone without replacing a gear and a piston.

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Guges Mk3
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Re: Gear Box WTF

Post by Guges Mk3 » Mon Jul 28, 2014 2:06 pm

Have you tried a different motor first before short stroking the mechbox?

Also...with a full length G3...I do not recommend short stroking it.
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Re: Gear Box WTF

Post by Archer » Mon Jul 28, 2014 5:13 pm

If I remember right, I think he said on FB that he got the problem solved.
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