Constant pinion gear stripping

[Baz]

Okay I'm on my third pinion gear in 3 outings with my M4 and it's pretty worn now. I'm using a guarder high speed motor with standard JG gearbox.
I've re-shimmed it regreased it and put new bearings in and it's still wearing fast.
Would a hardened pinion gear stop this or would a high speed gear set have any effect?
Or is this just a side effect of the high speed motor? Should I put a standard one in?

[richardy]

Re: Constant pinion gear stripping

guarder do a hardened one switch to that.. if you still curn through pinions after then somethings wrong, motor height, gearbox shimming being to tight or a part mismatch..

my old systema one went through loads till i switched to a guarder hardened one on the systema, stopped the problem in its tracks simply by replacing a part.. go to hardened.

[North West Outpost]

Re: Constant pinion gear stripping

If it is stripping on the teeth then motor height is not right. They will wear I have run those motors one was fine and one wore slightly.

If it is breaking teeth off then I would say something it very tight inside the gear box, when you have shimmed the gears and put the box back together. Without the motor on you should be able to easily move the gears from underneath with a small screwdriver. There should be a tiny bit of movement on each gear too, they shouldn't be forced inside the casing.

I wouldn't switch to the hardened one untill you have eliminated every thing else first.

[danhc]

Re: Constant pinion gear stripping

which teeth is it that are wearing? is it the ones that connect to the motor pinion gear or the spur one?

[ThatblokewiththeScar.]

Re: Constant pinion gear stripping

If you are on your third identical part then the parts are not the problem. The M120 motor is a pretty tuff bit of kit although I have stripped one myself.

As mentioned above the most likely culprit is motor height. If it's to low the pinion gear skims the bevel gear instead of engaging the gear this wears it quickly and causes heat to build up and Bang that's your lot. If it is set to high it puts undue strain on the gear and it's the same story.

Be careful when you replace the next one as repeatedly changing this part on the motor can make the pinion gear loose and this is also bad.

Do you have another motor you can use in the gun? If you pop in another motor and the same thing happens then you know it's not a problem with the M120 itself and is almost certainly the motor height. And if it runs fine and does not blow it's self into next week then perhaps your M120 motor has a bent axle.

[richardy]

Re: Constant pinion gear stripping

If it is stripping on the teeth then motor height is not right. They will wear I have run those motors one was fine and one wore slightly.

If it is breaking teeth off then I would say something it very tight inside the gear box, when you have shimmed the gears and put the box back together. Without the motor on you should be able to easily move the gears from underneath with a small screwdriver. There should be a tiny bit of movement on each gear too, they shouldn't be forced inside the casing.

I wouldn't switch to the hardened one untill you have eliminated every thing else first.

hes already said he reshimmed. sounds like hes thought about it yet still come a cropper.

hes gone through 3 ordinary ones, surely at this point you think "if only there was a harder stronger pinion gear out there i could fit to prevent the pinion gear grinding into a tiny nub on the end of my motor"

First he rules out the swiss cheese pinion gear which everyone strips... then if you break the pinion gear that no one strips you then start messing about with the mech box trying to figure it out.

hardened first then run it for 100 - 300 rounds, then examine it for wear. if you want to do it at short intervals more often thats fine.

Just dont run it untill it breaks this time catch it in the act.

Sometimes, hard gears vs soft metal pinion theres nothing you can do, upgrade since you have the option.

and theres no point chucking it in for another motor since they all probably come from the same factory anyway!

[North West Outpost]

Re: Constant pinion gear stripping

hes already said he reshimmed. sounds like hes thought about it yet still come a cropper.

hes gone through 3 ordinary ones, surely at this point you think "if only there was a harder stronger pinion gear out there i could fit to prevent the pinion gear grinding into a tiny nub on the end of my motor"

First he rules out the swiss cheese pinion gear which everyone strips... then if you break the pinion gear that no one strips you then start messing about with the mech box trying to figure it out.

hardened first then run it for 100 - 300 rounds, then examine it for wear. if you want to do it at short intervals more often thats fine.

Just dont run it untill it breaks this time catch it in the act.

Sometimes, hard gears vs soft metal pinion theres nothing you can do, upgrade since you have the option.

and theres no point chucking it in for another motor since they all probably come from the same factory anyway!

Glad you know so much about these things. Next time I get a problem I'll give you a shout....

[Baz]

Re: Constant pinion gear stripping

Thanks for the advice guys! I swapped the motor height washer for a better plate just before the last gear went so it could have been some existing damage caused by inadequate height that led it to go. It seemed to be running a lot better with the spacer so I'll see how it goes.

I've ordered 2 guarder hardened pinion gears to replace the busted one and I've got a standard TM motor to pop in for testing. I'll let you know how it turns out.

[richardy]

Re: Constant pinion gear stripping

tm motor pinions prity tough should last well espicially now youve got the spacer in and the correct height.

Youll have to knock the hardend pinion on to the shaft when it arrives.. i applyed a little glue and then used a hammer..

There is a special tool available under airsoft tool sections though

[Baz]

Re: Constant pinion gear stripping

Well I just swapped the pinion gear and I'm having the same problem. A slight movement and then nothing. I'm so sick of this gearbox and all it's problems I might as well just chuck it and buy a new one. It'll probably be a lot cheaper than getting this one repaired.

[richardy]

Re: Constant pinion gear stripping

hi,

what do you mean by slight movement then stop ? i thought the problem was striping pinion gears ?

[Baz]

Re: Constant pinion gear stripping

The motor only moves till tension is put on the gearing then it's like it just doesent have the power to pull. I reackon all the gear stripping stress has done a number on the motor and busted it as it's a high speed not high torque.
I've ordered a trouble free gearbox that I'm going to keep stock and unmodified to guarantee a working aeg and this one is going to get the full upgrade.

[Baz]

Re: Constant pinion gear stripping

Ok I had a quick test of the motor out of the grip and I can stop it with one finger. Definateley busted.

[richardy]

Re: Constant pinion gear stripping

Theres not much to a motor, as long as the current in is sufficent it should work, make sure the contacts are tight...

also try two wires direct from a charged battery to the motor and see if it increases its power at all..