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I reshimmed my kwa gearbox cuz it needed it, as do all gearboxes. but for some reason it is louder than normal, any reason why that may have happened??

loose, tight, or the hights dont match up.

JumpGunner wrote:loose, tight, or the hights dont match up.

aka, you didn't shim it well enough.

Did you test your shimming with the gearbox screwed together? KWAs are a little difficult to shim because of their tolerances, they don't always allow enough room to shim the gears very well. I've had a few where the gears were almost fused with the bearings, making it impossible to shim the gun.

ok, i got a new set of shims in so i will work on it this week. thanks.

make sure they include .01 shims. these are extremly valuable when you shim a tight gearbox.

.02, .03, and .05. i had put .01 in it when i reshimmed it

you do know you can put more than one shim in at a time right. I had a gearbox that needed .08 to work right. so 1 .05 and a .03. agm gear boxes are poop.

JumpGunner wrote:you do know you can put more than one shim in at a time right. I had a gearbox that needed .08 to work right. so 1 .05 and a .03. agm gear boxes are poop.

KWA gearboxes are designed with almost no room around the gears. Shimming usually only takes 1 or two shims because there's no room for extras. There's a reason why I don't like KWAs.

Star_folder wrote:

JumpGunner wrote:you do know you can put more than one shim in at a time right. I had a gearbox that needed .08 to work right. so 1 .05 and a .03. agm gear boxes are poop.

KWA gearboxes are designed with almost no room around the gears. Shimming usually only takes 1 or two shims because there's no room for extras. There's a reason why I don't like KWAs.

yea, i followed dom's video and do them one at a time and re tighten to check for any wiggle room, and then adjust if needed. so i am hoping the .02 and .01 are all i needed, to quiet the sound of the gears turning

Did you check the motor height, or how the motor meshes with the bevel gear?

^My bet is on motor height or the bevel gear being too low. When you had NOTHING in the GB except the shimmed gears and bearings, and torqued down all the screws, the gears spun easily, but without lateral wobble on the axles? If so, check to see that the bevel is not shimmed so low as to be causing excess friction against the pinion, and that the motor isn't simply mounted too high or low in the first place. Also, make sure you don't have any crap (dirt, filings) inside of the bearings themselves.