G36 v3 gearbox over-spinning

[Dire_Wolf]

Ok, here's an interesting issue...

I have a TM g36c, gearbox has a couple minor upgrades, like a poly piston, bearing spring guide, supposedly an upgraded spring (i have my doubts), and a new nozzle....

now, in semi-auto, one full trigger pull will turn the sector gear one full rotation, and then it will continue (on inertia, I assume), pick up the piston again, and stop with the piston slightly pulled. The next time I pull the trigger, the same thing happens, but there is slightly less inertia, and the piston doesn't get pulled back quite as far on the second rotation. the end result is that the tappet plate and nozzle don't end up in the same place every time I pull the trigger, and the piston never rests at full discharge. yes, i've seen the "trigger glitch" posts and no, I don't quick tap the trigger... this is from too much trigger, i'm thinking... not too little.

Now, I'm pretty sure the issue is with the cutoff lever not acting early enough, but I'm not sure what to do about it. is there a certain way the springs in the trigger assembly have to be installed for the lever and such to work properly?

Wolf

[Styrak]

Is it an old gun? The cutoff lever might be worn down.

[The Saint]

What battery are you using?

[Dire_Wolf]

huzzah! replies! um...not terribly sure how old it is... i've ordered a new v3 cutoff from airsoftparts.ca that should be here within the week, we'll see if that helps... and i'm using an 8.4v mini 1500 and 1600 mah.... also have a 9.6v 1400 that is a very very tight squeeze in the stock handguard... does it on all three batteries, and I'm mostly testing outside of the shell, bypassing the fuse wires and hopup entirely. I put the magwell on the gearbox with the keyed pin to judge where the nozzle is ending up, but the gearbox is essentially on its own...

[The Saint]

If you can find nothing wrong with the parts, you can stop this over spin by using a slightly stronger spring.

[Spa]

Semi auto- takes more battery juice because of the fact that the spring is already pre-compressed therefore requireming more force to compress the spring all the way back like you mentioned. From what you are saying, seems normal for semi auto. It is normal because in semi it does not fire the piston and leave it right back at the cylinder head, it actually sets up the piton pre-compressed. Full auto is what puts the piston back at the cylinder head. It just a couple pulls to put it there

It seems normal for what your AEG is doing.

[Dire_Wolf]

if it was normal, wouldn't the tappet end up in the same place every time? it's causing bb feeding issues... i also have a pom sector clip on the way...

[The Saint]

Slightly excessively cycling is normal. AEGs don't cycle exactly the same shot to shot. It's nothing to worry about.

[SHÖCK]

On mine, the cutoff lever was completely worn smooth after a year while using heavy helical gears. I replaced it and that old gear set.

[screwdriver]

all my aegs apart from my marui m4 do this, to alleviate the problem i just lightly tap the trigger in semi to pull the piston back in stages and then the final tap releases the piston ready for storage.
this is why ive never understood why all aegs dont have the spring release lever like the ics m4 and g&g sa80 has.
though as mentioned before some guns ive upgraded for others were prone to doing this but stopped after the springs were greatly upgraded.
an extra note is that if your semi cut off lever wears greatly youll loose semi completely and have full auto only, the torque in the gear set with a lower power spring will continue rotation even after the cut off lever cuts power to the motor

[Dire_Wolf]

ok, sounds good... i have a stronger spring coming as well, i figured might as well... my biggest issue with the whole affair is the bb feeding problem, since it won't always feed right because of the nozzle difference... I'll have to see if the pom sector clip helps that...

[milehigh]

Originally Posted by Spa

Semi auto- takes more battery juice because of the fact that the spring is already pre-compressed therefore requireming more force to compress the spring all the way back like you mentioned. From what you are saying, seems normal for semi auto. It is normal because in semi it does not fire the piston and leave it right back at the cylinder head, it actually sets up the piton pre-compressed. Full auto is what puts the piston back at the cylinder head. It just a couple pulls to put it there

It seems normal for what your AEG is doing.

Wrong. Full auto leaves the spring compressed.

Your problem is most likely your bevel gear. I had this same problem on my G36. The stock bevel gear only had 2 anti-reversal latch notches. This can cause a double-feed in your hop-up chamber. When the gun fires in semi, the gears pick up a bit of momentum and slightly start another mechbox cycle (pulling the nozzle back). The spring will want to return forward after the shot, letting the nozzle close (loading a BB). When you go to fire again, you start with a new gearbox cycle and load a second BB.

If you have more notches on your bevel gear, the gearbox wont be able to "reverse" after starts a cycle.

[Dire_Wolf]

except that the bevel gear carries the most rotations of any of the gears. the sector gear turns once per shot, the spur gear turns maybe 4 or 5 times(estimating, not certain), and the bevel gear will turn 4 or 5 times per spin of the spur gear.... and each rotation of the bevel gear will have two points to catch on the anti-reversal latch.... so basically, wherever the inertia stops moving the gears, the spring won't be able to move the gearset back very far because there will be a reversal lobe in close proximity. nowhere near enough movement of the nozzle forwards to load a bb. i could see perhaps knocking the bb out of the straight line, causing the bb under it to get some spherical leverage and push it out of the way into the hop up... but i can't see another two lobes changing the loading that much...

[SHÖCK]

I don't see a sector clip doing anything to solve this.

I hate them personally, but the only real way to get normal AEGs to go through perfect cycles each and every time is to get a mosfet. Otherwise, this is going to happen from time to time because of momentum and different ways you hit the trigger causing the motor to spin.

[milehigh]

Originally Posted by Dire_Wolf

except that the bevel gear carries the most rotations of any of the gears. the sector gear turns once per shot, the spur gear turns maybe 4 or 5 times(estimating, not certain), and the bevel gear will turn 4 or 5 times per spin of the spur gear.... and each rotation of the bevel gear will have two points to catch on the anti-reversal latch.... so basically, wherever the inertia stops moving the gears, the spring won't be able to move the gearset back very far because there will be a reversal lobe in close proximity. nowhere near enough movement of the nozzle forwards to load a bb. i could see perhaps knocking the bb out of the straight line, causing the bb under it to get some spherical leverage and push it out of the way into the hop up... but i can't see another two lobes changing the loading that much...

It solved my problem with double feeds.