Gears destroying my pistons in a few seconds, any ideas?

[LeoGaunt]

I put my gearbox together and fired a few shot before I then realised the piston wasn't engaging with the gears, took It apart to find the first tooth had been ripped off completely.

luckily I had a spare and assumed i was just unlucky, so I put it back together with a new piston, which after shooting for a few seconds again, got all the plastic teeth completely worn down with a huge groove until it was no longer engaging with the gears.

Also the air from the gun wasn't powerful at all. Anybody got an idea how this can be possible and why my gear is wearing down the piston so quickly, my gearbox desperately need shimming but I don't see how this problem has occurred, any help appreciated thanks!

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View attachment 13077

 

[Mack]

I'm no tech but that looks like a pre engagement problem, Re you running a high ROF setup?

 

[straffham]

when you re-assembled the gearbox did you check the piston movement ie using a thin screwdriver or similar inserted via the air nozzle? I've known the occasional piston be too tight in the gearbox, but it only shows once the gb is screwed shut hence why I always now check this as above.

What gun is it from and what else have you changed in the gearbox? As Mack says if you,ve upped the spring/torque/speed then this can happen if something isn't set up 100%, although it doesn't usually happen the first time you pull the trigger which is what makes me suspect the piston not moving correctly.

 

[Samurai]

Also, check the angle of engagement.

 

[LeoGaunt]

I put a g&p m120 high speed motor in, I didn't really check before putting it together, everything else was stock apart from the shim arrangement as they fell out everywhere and I didn't spend too much time putting them back in and lost half of them,

What do I need to do to adjust angle of engagement?

Thanks

 

[BrightCandle]

I put a g&p m120 high speed motor in, I didn't really check before putting it together, everything else was stock apart from the shim arrangement as they fell out everywhere and I didn't spend too much time putting them back in and lost half of them,

What do I need to do to adjust angle of engagement?

Thanks

So you have a load of gears that are wobbling about, vibrating on every shot back and forth, transferring all that wobble to the poor plastic piston and you are wondering why it is that the piston got stripped? Is this a joke of some kind I am missing?! Mechanically you are really mistreating those poor gearbox components its no wonder bits are failing. Its time you took this to a tech to get this sorted, I don't think you have the mindset for teching.

 

[LeoGaunt]

So you have a load of gears that are wobbling about, vibrating on every shot back and forth, transferring all that wobble to the poor plastic piston and you are wondering why it is that the piston got stripped? Is this a joke of some kind I am missing?! Mechanically you are really mistreating those poor gearbox components its no wonder bits are failing. Its time you took this to a tech to get this sorted, I don't think you have the mindset for teching.

yeah I understand this, but it was fine before, I had put it back together and was using it numerous times without the shims in properly and it wasn't having too much of a problem, I've been quickly taking it apart and putting it back together because I've been having problems with the semi auto on the two stage trigger not working well.

I'm not too bothered about the parts that broke since i brought an upgrade kit and some shims a few days ago so i'm going to take the time to set it up properly, I'm just wondering why its so worn down and what could be causing the rapid wear, so I don't make the same mistakes with the new parts. I don't see how a slight wobble will cause it to completely strip it in 20 shots, that's something much worse.

 

[n1ckh]

Like on any gear/cog setup, if its not meshed correctly then you will always strip gears

 

[LeoGaunt]

i'll take my time to set it up nicely when my parts come, youtube shimming tutorials and everything, thanks guys

 

[mr-bodycounter]

I don't know how terribly it was shimmed but that is almost as if you coated the gears in acid as well. You will probably have to buy a new piston now but buy a piston with some (preferably all) metal teeth, and LEARN TO SHIM WELL, there is thousands of good tutorials out there just watch them and when it comes to it, take your time, better to spend 6 hours shimming and have a gun that lasts for 6years than spend 5 seconds shimming and have to repair your gun every 20 shots. Also, look at AOE (there is a good video by ASTKilo23 out there which explains everything really well).

 

[loader]

Like on any gear/cog setup, if its not meshed correctly then you will always strip gears

What nick said sounds bang on. I have raced Rc cars for a few years and this is exactly what happens when the gears and pinions aren't meshed properly. It sounds like the gears and pinions aren't close enough in together.

 

[n1ckh]

I'm assuming that airsoft gearing are all standard 'tooth pitch' or are they like rc car makers where they have there own gears that won't work in other cars ??

I do the same as Loader but with rc boats aswell, I've stripped many gears in my cars due to incorrect gear mesh or tooth pitch on the gears not matching

 

[Cheeky vimto]

Also keep in mind if you get a full metal toothed piston and don't put it back together properly you will damage the gears aswell as the piston. This is the reason I stick with plastic, if it goes wrong it's usually a cheaper repair. All you really need is the first tooth in metal.

 

[jcheeseright]

yeah, piston for me is a mechanical fuse... the piston will strip long before I damage my expensive gears or motor.

 

[Airsoft-Ed]

Might sound obvious, but did you check the barrel for jams? The only time I've ever stripped pistons to the same extent as that, it turned out the barrel was jammed, so the air blockage just caused the piston to get stuck at the rear because the air couldn't escape fast enough, and then the gears just sawed it to shit.