gearbox sound

[God]

Quick question, when I let the trigger go mid-cycle of full auto, I believe I am hearing the gearbox unwind. Is this a bad thing?

[pappyjump]

I believe this is due to your anti reversal latch being broken or out of place. It happened to me once in my old Dboys SCAR

[Switchback]

Anti-Reversal Latch. You need to get it replaced or replace it yourself.

[God]

Okay, but is it that bad of a thing? I mean, it almost sounds like a good thing. So I know it isn't jamming up the gearbox. It only uncycles(no, that's not a real word) for a half a second. Long enough for it to push the piston back forward it sounds like.

[Minerva]

No its really not a good thing. If your gears are spinning backwards, thats going to cause a bunch of problems if its not promptly fixed.

[Blizzard]

No its really not a good thing. If your gears are spinning backwards, thats going to cause a bunch of problems if its not promptly fixed.

Really? Like what?

No, it does not hurt your gun. It's actually better if the gearbox is relaxed. It could cause double feeding since the air-nozzle will cycle twice if the gearbox unwinds, but other than that, it won't actually cause wear.

Just put a new one in and you'll be good to go.

[Minerva]

Having your gearbox cycle in reverse puts unnecessary wear on your piston teeth and tappet plate. Depending on how the anti reversal latch broke (at the gear teeth, fulcrum or spring) will be very dependent on how much damage it can cause. If it just wore down at the teeth or the spring stopped functioning there will be less damage and more of annoyance, but as said earlier, what is the point of using a broken part in your gearbox? Thus the suggestion to replace it promptly. If you were to pull the trigger while the gears were unwinding, you would rake the teeth on the piston and strip it

[Jester316]

I ran my Mp5 with out an anti-reversal latch for months with no ill effects. Would I replace it when I can? Yes. Is it a big deal if you don't have it? Not really.

[pappyjump]

Yeah dont be in a big hurry to fix it, its really not a big deal for a little while.

[Minerva]

As I said earlier, it's not necessarily vital to the function of a gun, however, it still puts unnecessary wear on parts if conditions are met. And at $10, why cause an annoyance and take that chance?

[Jester316]

How does it put stress on the gearbox? I'd argue that having the latch puts MORE stress on it.

With latch: If the GB half cycles, the piston stops in a mid stroke position, with pressure from the spring pushing it forward. That pressure is steady on the teeth of the piston and gears.

Without latch: If the GB half cycles, the piston returns to a forward position, keeping the spring uncompressed. This keeps pressure off the piston teeth and gears.


Obviously there is a reason why the part is included in a gearbox, however I've run a gun without it for many thousands of rounds without it. I sold it without it, and I'm not sure if he put one in. If you have the money fix it, if you don't it's not going to shoot your eye out.

[God]

I'm probably not going to replace it.. Reasons, I use semi primarily anyway, I kind of like to know my spring is not locked back, and finally, since my trigger pull is pretty crisp(there's a clear place where it clicks to fire), I doubt I will fire again in the half a second it is unwinding. So, thank you for your input. I am glad it is not vital, as I don't enjoy the idea of another gearbox foray.

[Nox]

If you were to pull the trigger while the gears were unwinding, you would rake the teeth on the piston and strip it

THIS.
If the piston and gearset is moving and you pull that trigger while all that pressure is moving forward, it could put ALOT of strain on the gears - and if they aren't steel then the torque or pressure could start snapping teeth.

[Switchback]

How does it put stress on the gearbox? I'd argue that having the latch puts MORE stress on it.

Question, Sir:

Are there not MOSFET chips that turn the motor exactly one cycle, thus eliminating the need for an anti-reversal latch?

(I would imagine using LMG's/MMG's without AR latches would be fine due to the whole laying down long bursts bit)

[Minerva]

How does it put stress on the gearbox? I'd argue that having the latch puts MORE stress on it.

He stated it broke INSIDE the gearbox. That could mean it snapped at the fulcrum and he has a loose ARL hanging in. Or the spring could have given way and its just wobbling around, in which case if it engages the gear, theirs going to be some catastrophic failure. I didn't mean for my post to be taken as it was bad if it wasn't present, but to have a broken piece inside the gearbox is bad.

Yes Switchback there are. They are called AB Mosfets and they brake the motor after a complete cycle.