Drive gear shaft has play in it

[robertjpjr]

I'll try and describe this as best as I can.
The drive gear within the transmission has a slot that fits around the shaft that the spur assembly attaches to.
My problem is that the shaft slides in and out at the drive gear. This causes the spur gear to shift one way or the other horizontally perpendicular to the motor.
I fixed this by spacing the gap between the transmission case the the back of the spur assembly. Took the play out, but not sure of the actual reason for the play in the first place.
Anybody had this happen???

[TacoCrawler]

mine had similar play at the gear shaft that the spur gear mounts to.
I put a coupla' thin washers behind the shaft's cross pin.
seems to have done the trick, haven't dealt with it since.

Mine was a sealed new RTR...
so it came that way from the mfg'r !?

the washer fix seems to work acceptably.

...I also wondered if this was a common thing ?

[jeepnvinny]

Mine does it too. I'm thinking that it is common. BTW, I'll have to try the washer approach as it sounds like a good idea:-)

[Reaxion911]

Yup two or three axle shaft shimms take that slop out. They sll do that from factory. I would put the shims in as the slop is between the cross pin and the top gear in the trans and is allowing the pin to almost come out of the top gear.

[TacoCrawler]

The slipper plate's inner shank's seat (surface)
actually seats past the pin slightly when pressed on.

If the washers (shims) are too thick...
They will not allow the slipper plate to seat fully
on that pin.

I used thin Traxxas washers as shims.
I needed two of those to make the correction.

I found that adding a third washer was too much...
and that extra thickness would push the slipper plate
outward and off that pin.
As well as causing some friction or bind.

Properly shimmed...
the slipper plate seat should not be sandwiched
tightly against the shims (which rest against the bearing)

If there is no play between the shim
and the inner surface of the slipper plate...
It could cause issue down the road.

^ possibly causing premature wear issues for the mechanical hardware
and over-heating with electronic components.

Once shimmed... hand spin the spur gear/slipper plate
and be sure there is no friction or bind there.
It should turn smoothly and without resistance.

[Reaxion911]

Right o a couple thou. of play is good. I used some tra xxas washers too. One of my rigs took two the other three. As with anything check for binding after any mods.

[Meatwad]

Pretty much any ax/scx tranny I've been in contact with has had this slop. A couple shims work

[TacoCrawler]

Originally Posted by Meatwad

Pretty much any ax/scx tranny I've been in contact with has had this slop. A couple shims work

yeah... but the question that should really be asked... is

why hasn't Axial made correction ?

[raceeng18]

Originally Posted by tacocrawler

yeah... But the question that should really be asked... Is

why hasn't axial made correction ?

money

[Meatwad]

Originally Posted by TacoCrawler

yeah... but the question that should really be asked... is

why hasn't Axial made correction ?

It doesn't seem to make a difference imo, I shimmed it to sleep better at night.

Originally Posted by raceeng18

money

This. A tight tolerance rc would eventually have diminishing returns for the cost.