Loose Bushings

[Gilligan]

Hey guys,
I'm working on my V2 gearbox, and my metal bushings are super loose, they're popping out with barely a touch and its making shimming somewhat difficult, (like when I go to press on the gear axle to test play it moves both bushings and gear). Just wondering if this was a normal circumstance, if it doesn't really matter or if its something that needs to be fixed immediately. Also my gearbox has been locking up a lot recently, and I was wondering if that could be contributing (like too much play in the gears).


Thanks!

[Reeko]

locked up gearboxes are usually caused by:

-improper shimming
-worn down cut-off lever
-less than sufficient battery, or one that is almost dead.

cutoff lever comparison


(credit to Jawz from Airsoft Snohomish)

as for the bushings, if you purchased new bushings, its likely that they are the wrong size, there are 6mm, 7mm, and 8mm bushings. Make sure you have the correct size for the gear box. Thats about all i can help with as far as bushings go unfortunately.

[Gilligan]

I've measured the bushings and the holes, they both look the same (7mm). I've seen posts on other websites that say to superglue the bushings in, but I wasn't sure about that. Could a warped AR latch also cause lockups? The latch is a little tweaked but it still fits in the GB.

[spazzticsmurff]

gluing the bushings in is going to be what you want to do but you need to make sure that the bushings are seated correctly or you are going to cause more problems then you will fix by gluing them in.

[Spartanacus]

Overshim the gearbox when you glue in bushings, that is, add one more thick shim to each gear than what is ideal. Close the gearbox and tighten it down. This will force the bushings flat against the shell while it dries. Use epoxy for best results.

[Jewish Ninja]

Get a pair of calipers and measure the bushings and bushing holes to make sure they are the correct size (it sounds like you bought the wrong size). Gluing them in is a horrible idea which can lead to your GB going kaput quicker than normal.

[Payback]

Get a pair of calipers and measure the bushings and bushing holes to make sure they are the correct size (it sounds like you bought the wrong size). Gluing them in is a horrible idea which can lead to your GB going kaput quicker than normal.

+1

Depending on your gearbox, not all bushings/bearings are going to stick in tight. As long as when they are in the hole, it doesn't wobble around in it (giggity giggity). I have several GB's that are loose and some that need to be tapped in with a vinyl mallet to get them to seat.

If anything to help you shim them, i would put extra grease on them to get them sticky and stay put while you shim. If they wobble around, then your box is worn out and needs to be replaced, or try another set of bearings first. I highly doubt you have the wrong size, as it's really obvious when you put in a 7mm bushing into an 8mm hole, you would have to be blind to not know that is what the problem was.

Glue is a horrible idea, one, it's not meant to be there, two, once it's put together, it wont hold after the first cycle.

[Gilligan]

Thanks guys for all the input, I really appreciate it. I bought the gun a couple weeks ago off the classifies here, and I'm downgrading it to Indoor FPS. The main issue I'm seeing is that some of the bushings are spinning when I spin the gears, and also when trying to shim the bevel gear specifically, the bushings will move with the gear when I'm trying to test the play, so I end up moving both the bushings and the gear all at once. I'm just looking for a fix that wont end in another $65ish for a new GB shell.

[spazzticsmurff]

If anything to help you shim them, i would put extra grease on them to get them sticky and stay put while you shim.

wrong, when shimming your gb it should be void of grease. grease will give you false readings because it takes up space. if the grease you have put in between your bushings and gb to keep your bushings in place takes up .1mm of space or that you put between your shims to keep them in place, your shimming can end up off by more than you think it can. if you dont have anything between your bushings and shims and gears, then you actualy know what your tolarences are. grease, after a while can end up getting pushed out from between bushings and shims over time and if that happens then that cushion that was there because of the grease you left in place, is no longer there and you can cause gear train issues,(of course if the grease is gone your going to have problems anyways.

Get a pair of calipers and measure the bushings and bushing holes to make sure they are the correct size (it sounds like you bought the wrong size). Gluing them in is a horrible idea which can lead to your GB going kaput quicker than normal.

Glue is a horrible idea, one, it's not meant to be there, two, once it's put together, it wont hold after the first cycle.

while having a quality set of callipers is allways a good idea, it seems to be the only correct one in the prior quote.
gluing your bushings/bearings in properly will do nothing but help. when done properly it will help keep your drive train in alignment. loose bushings can and will rotate and even with grease will cause the holes to wallow out further which will cause you gear shaft center to center distances to be off and will shorten the lifespan of your gears.

if the adhesive you are using to glue down your gears doesnt hold after 1 cycle or even 1000 cycles then you are not doing something right. allways remember, grease will inhibit adhesion so clean your gb thoroughly. dawn, fast orange, or any other grease cutting soap fallowed by alcohol and posibly even a surface prep designed for the type of adhesive you are using will go along way to make sure the job is done right. useing a quality adhesive instead of cheap crap from the local dollar store will also help alot.
i recently had to remove sector gear bushing because of a sector gear that sheared the shaft and wallowed out the cheap modify bushings that i was stuck using. i had to use a brass bushing driver and supports under the gb to get the bushings loose. and that was after they had been in there for 4 very hard months and had about 30,000 cycles on through it.

[Payback]

Glue is stupid, your putting a bandaid solution on a bigger problem. You can pick apart my suggestions all you want, but the fact is I'm not offering options that aren't proven to work.

If your worried about .001 thickness of grease, show me a glue that is thinner, and if you shim your box that tight, just as in your argument, what happens when you add grease? You have over shimmed it till the grease moves.

[Gilligan]

Got my hands on some calipers, and the measurements seem to be on within .05 of a mm. My main issue is that A) My bushings are spinning freely in the GB, and B) When I put them in the GB shell and flip it over, they fall out easily. Also, my gearbox shell is completely clean, not an ounce of grease left on it.

Depending on your gearbox, not all bushings/bearings are going to stick in tight. As long as when they are in the hole, it doesn't wobble around in it (giggity giggity).

When you say wobble do you mean side to side in the shell, or in and out of the seating?

[spazzticsmurff]

Glue is stupid, your putting a bandaid solution on a bigger problem. You can pick apart my suggestions all you want, but the fact is I'm not offering options that aren't proven to work.

If your worried about .001 thickness of grease, show me a glue that is thinner, and if you shim your box that tight, just as in your argument, what happens when you add grease? You have over shimmed it till the grease moves.

you say glue is a bandaid solution. then wouldnt putting grease to hold the bushings in place be the same thing? that and replacing the gb are the only things you said to do. at least glueing the bushings down will hold the bushings in place and keep them from wallowing out the holes further, unlike using grease to hold the bushings in place.
thickness of the glue is of lil importance since it is done prior to shimming and will hold the bushings in place and not get pushed after a few cycles when the bushings start rotating in there sockets because you provided the lubrication for them to do so.
the glue i use is a very thin ca glue that wicks itself into the lil creaveses. it is very strong and is used to hold the bushings in place before i start shimming so that i get my shimming to the exact tolerences that i want them to be.
recomended end play from the gear master riotsc is .003-.004". i like to set mine at .003" i set mine using a dial indacator. when greased the gb has less than .001" of end play.

but since we are talking about other methods you can also ream the bushing holes to take a larger size bushing/bearing. you have to be very carefull with this method as it is very easy to get the hole off center or to large.

locked up gearboxes are usually caused by:

-improper shimming
-worn down cut-off lever
-less than sufficient battery, or one that is almost dead.

i have never seen a gb lockup because of a worn out cutoff lever the only thing the cut off lever does is control semi auto. it will ocassionaly lock up the trigger because of tolerance issues but a fip of the switch to full auto and the gun starts firing again.

thank you for your time.