Trigger locking when firing.

[Dan Robinson]

Every so often - as in a couple of times on a game day - my gun's trigger seems to jam. 

 

It is quickly fixed by moving the selector switch from whatever firing mode it's in to the other, and back again. 

 

 

Is this something to worry about?  Or is it a "shit happens" kinda thing? 

 

Thanks in advance. 

Edited June 19, 2022 by Dan Robinson
Grammar

[EDcase]

That's a lockup which happens when the trigger is released too quickly for the gearbox to finish a cycle.   Switching to auto just finishes the cycle as it ignores the position of cutoff lever.

This is one of the benefits of using a more advanced MOSFET which can monitor the gears and automatically completes a cycle even if the trigger has been released.

 

Its not really bad for the gearbox but a battery with higher C rating will help as will learning to hold the trigger until a shot is complete.

 

 

Edited June 19, 2022 by EDcase

[Dan Robinson]

Cheers.  As per the other thread I'm browsing for a higher c battery now anyway.

 

I'll have a look at MOSFET changing threads as well while the F1 is on. See if it's as easy as it looks with my one hanging in the breeze. 

[Skara]

It's a "timing issue" that occurs when the cycle stops right to the point where the cutoff lever engages the trigger trolley too early and said trolley is lifted from the trigger before closing the circuit.

 

It's unavoidable and an inherent design flaw of AEGs.

 

To permanently eliminate the issue you need a mosfet with cycle detection (replaces the cut off lever) like a Gate Titan/Aster or Perun Optical/Hybrid.

[Dan Robinson]

Still need to research the cleverer MOSFETs.  I'm wondering how they know where the gearbox is in its cycle.

 

Glad it's not damaging the gun too much, and I suppose it adds a certain degree of real life fuckery when pew pewing.

[Skara]

44 minutes ago, Dan Robinson said:

I'm wondering how they know where the gearbox is in its cycle.

They have a sensor that reads the sector gear's teeth when they pass by and does some math to figure it out (Titan), or they have a sensor that reads the sector gear's cam (the one that engages the cutoff lever).

 

Other mosfets like the old BTC Spectre or the G&G ETU still rely on a mechanical cutoff but it activates a microswitch instead of being read by an optical sensor.

Edited June 20, 2022 by Skara

[Lozart]

30 minutes ago, Dan Robinson said:

Still need to research the cleverer MOSFETs.  I'm wondering how they know where the gearbox is in its cycle.

 

 

The Gate mosfets (Titan and Aster) use photocells to pick up the teeth on the gear (the Titan is a break beam, the Aster is retro reflective which is why it has stickers to put in the gearbox). The issue with optical sensors is that they can get dirty and stop working or you can sometimes get too much ambient light into the gearbox that interferes. With the Aster needing a white surface opposite the sensor, you can run into issues if the sticker isn't flat or doesn't adhere to the inside of the gearbox properly.

 

The Perun Hybrid uses a hall effect (magnetic) sensor to do the same thing. Arguably this is more reliable but both systems rely on correct spacing 

[Dan Robinson]

1 hour ago, Skara said:

They have a sensor that reads the sector gear's teeth when they pass by and does some math to figure it out (Titan), or they have a sensor that reads the sector gear's cam (the one that engages the cutoff lever).

 

Other mosfets like the old BTC Spectre or the G&G ETU still rely on a mechanical cutoff but it activates a microswitch instead of being read by an optical sensor.

 

1 hour ago, Lozart said:

 

The Gate mosfets (Titan and Aster) use photocells to pick up the teeth on the gear (the Titan is a break beam, the Aster is retro reflective which is why it has stickers to put in the gearbox). The issue with optical sensors is that they can get dirty and stop working or you can sometimes get too much ambient light into the gearbox that interferes. With the Aster needing a white surface opposite the sensor, you can run into issues if the sticker isn't flat or doesn't adhere to the inside of the gearbox properly.

 

The Perun Hybrid uses a hall effect (magnetic) sensor to do the same thing. Arguably this is more reliable but both systems rely on correct spacing 

 

 

That was what I was thinking - which means cracking open the gearbox.  Which I am far from comfortable doing at this stage of my limited experience.  If it was simply splicing some wires and soldering, then fine.  Especially as my gun has its MOSFET swinging in the breeze anyway.

 

But having spunked a lot more than I was planning on already with this sport, I think I can wait and chalk this one up to a little added realism.  I can save my pennies now for when I am in Japan and have access to a wider range of pew pews than I would here.  

[Speedbird_666]

I'm surprised no one has mentioned replacing the motor. 

 

I use SHS High Torque motors with 7.4v LiPos on all but one of my guns and I have never, ever had a lockup on any of them, even spamming the trigger in semi.

 

I do make sure that they are all reasonably well shimmed, but most of my guns are pretty much stock with the usual 18:1 standard gears with solid bushings and all teeth intact. 

 

You don't need an ETU to eliminate the problem.

[Skara]

7 minutes ago, Speedbird_666 said:

I'm surprised no one has mentioned replacing the motor. 

 

I use SHS High Torque motors with 7.4v LiPos on all but one of my guns and I have never, ever had a lockup on any of them, even spamming the trigger in semi.

 

I do make sure that they are all reasonably well shimmed, but most of my guns are pretty much stock with the usual 18:1 standard gears with solid bushings and all teeth intact. 

 

You don't need an ETU to eliminate the problem.

Nobody mentioned the motor because it's not the solution.

 

All you've done is introduce more overspin to lower the chances of the system stopping in the position I described above, but the issue (cutoff lever) is still there, and now you've introduced a new problem, which is the piston stopping in random places due to increased overspin, which leads to the spring being somewhat always compressed (but it's not consistent) which in turn increases stress on things like the piston, gears, bushings and such.

 

The only sensible way to permanently eliminate gearbox lockups (caused by the cycle itself) is to fuck off the cutoff lever and install an FCU with cycle detection.

[Rogerborg]

28 minutes ago, Skara said:

Nobody mentioned the motor because it's not the solution.

 

It helps though, and is a positive in itself.  I got a few lockups on my JG G36 with the stock meh motor and V3 2-piece trigger. Both the minor trigger-trolly issue, and also a proper fuse-popper when the spring ended up almost fully compressed and the stock motor stalled out and wouldn't pull it any further.

 

After switching to a Big Dragon M140, I never had another.

[Speedbird_666]

8 minutes ago, Skara said:

Nobody mentioned the motor because it's not the solution. [snip]

 

 

10+ years running a High-Torque/7.4v setup across most of my guns.  Never had any issues with 'additional stresses' or such like on my simple sub-350fps guns.

 

Never stripped a single gear, piston or damaged a bushing doing it. Never had any noteworthy FPS losses either.

 

So, for me, it is a solution. A simple one at that.  It's just that you don't like it. 

 

21 minutes ago, Skara said:

which leads to the spring being somewhat always compressed

 

Pedantry here: Main springs are always compressed in an AEG gearbox, even with the piston fully-forward. 😘

[Dan Robinson]

Well, now entirely sure the higher C rating has made a difference.... 

 

 

 

Granted these shots aren't under load, but see if you can guess which two bursts were the 2200mAh 40C, and which was the 2700mAh 10C.

 

 

 

 

Edited June 20, 2022 by Dan Robinson

[Shamal]

10 minutes ago, Dan Robinson said:

Well, now entirely sure the higher C rating has made a difference.... 

 

 

 

Granted these shots aren't under load, but see if you can guess which two bursts were the 2200mAh 40C, and which was the 2700mAh 10C.

 

 

 

 

Sound pretty much the same to me bud lol.

But I am deaf in one leg.🤣

 

[Skara]

2 hours ago, Speedbird_666 said:

So, for me, it is a solution. A simple one at that.  It's just that you don't like it. 

Not really, but you do you.

 

 

23 minutes ago, Dan Robinson said:

Well, now entirely sure the higher C rating has made a difference.... 

 

First and last bursts come from the 2400mAh 40c battery  It's not just the C rating, capacity (mAh) also plays a role.

2400 mAh battery dumps 88 amps (2400 x 40) while the 2700 mAh only dumps 27 (2700 x 10).

In your audio you can clearly hear how the 27 amps battery renders the gun sluggish while the 88 amps one gives the gun a much healthier sound.

[Adolf Hamster]

a faster motor (or more juice to the existing one) isn't a pure technical solution to the issue, but it can practically solve the problem by making a lockup scenario less likely, you can only pull and release a trigger so fast after all.

 

same applies to using mosfets like the ab++ or warfet, they don't remove the physical conditions for a lock to occurr but they can be setup to prevent the box ever stopping in the region where a lockup can occurr.

[Dan Robinson]

22 minutes ago, Skara said:

Not really, but you do you.

 

 

First and last bursts come from the 2400mAh 40c battery  It's not just the C rating, capacity (mAh) also plays a role.

2400 mAh battery dumps 88 amps (2400 x 40) while the 2700 mAh only dumps 27 (2700 x 10).

In your audio you can clearly hear how the 27 amps battery renders the gun sluggish while the 88 amps one gives the gun a much healthier sound.

 

Smarty pants 😜. 

 

I was of the thinking that under load, in full auto, there would be a more noticeable difference due to reduced voltage drop. 

[Skara]

There is, but yeah it's not overly exaggerated as one may think.

 

I still wouldn't use the 2700mAh battery though, if I'm not mistaken the motor you have (standard 14tpa ferrite) draws way more than 27 amps (talking 45 at least) and it will kill the battery quickly.

It's always better to have an oversized battery than the other way around.

[Adolf Hamster]

1 minute ago, Skara said:

It's always better to have an oversized battery than the other way around.

 

Qft, you want the motor to top out not the battery.