Granite Normal Slipper Play in Motor Mount?

[RCBro80]

Good morning,

I've just received some of the parts to upgrade my son's Granite Mega to brushless, and I have an easy question for the experts here. Is this play between the slipper and the motor mount normal? I studied the exploded view and I don't see anything missing, so I'm assuming the driveshaft will hold this in place when fully assembled. Is that right?

 

[vader]

I believe that’s fine, I have done the same upgrade, the sprung centre drive shaft will keep it more in place once installed. I’m still quite new to the hobby though

 

[Yas]

It's normal, but you might want to use 15mm OD shims to negate that play. I used HPI 101291 shims

The spur usually grinds on the plastic motor housing and creates a black powdery dust that will eventually destroy the bearings, including the motor bearings

Great catch by the way I feel this is a must do for all of the Arrma 4x4 cars

 

[Exc3l]

It's normal, but you might want to use 15mm OD shims to negate that play. I used HPI 101291 shims

The spur usually grinds on the plastic motor housing and creates a black powdery dust that will eventually destroy the bearings, including the motor bearings

Great catch by the way I feel this is a must do for all of the Arrma 4x4 cars

I should look into this since I run 6s in these 4x4 cars...

 

[RCBro80]

It's normal, but you might want to use 15mm OD shims to negate that play. I used HPI 101291 shims

The spur usually grinds on the plastic motor housing and creates a black powdery dust that will eventually destroy the bearings, including the motor bearings

Great catch by the way I feel this is a must do for all of the Arrma 4x4 cars

Thanks! I've heard (or seen pictures) of rubbing, but I wondered if they had installed the slipper backwards.

I'm trying to rationalize the mechanism that would cause the slipper to move forward under spring tension from the driveshaft... either way, that sounds like a simple fix.

 

[Yas]

Thanks! I've heard (or seen pictures) of rubbing, but I wondered if they had installed the slipper backwards.

I'm trying to rationalize the mechanism that would cause the slipper to move forward under spring tension from the driveshaft... either way, that sounds like a simple fix.

Yeah the spring tension from the driveshaft is what pushes it backwards. I found it rubbed most against the rear side housing because of this. Once it's shimmed you might have less rolling resistance too

 

[jondilly1974]

Good morning,

I've just received some of the parts to upgrade my son's Granite Mega to brushless, and I have an easy question for the experts here. Is this play between the slipper and the motor mount normal? I studied the exploded view and I don't see anything missing, so I'm assuming the driveshaft will hold this in place when fully assembled. Is that right?

It is normal to see it, but not really optimal IMO. You can shim the bearings to remove the slop.

 

[RCBro80]

Ohhhh, I was going to ask, but I thought the potential rubbing was on the front side (due to the play).

Interesting... no matter how hard I push the slipper backwards, I can't make it rub. Maybe Arrma has been adjusting the tolerance of the step on the slipper hub to prevent this?

Now that I think about it, the user who posted images of the destroyed spur and housing had forgotten the front bearing, which allows the slipper to rock and rub quite badly.

It is normal to see it, but not really optimal IMO. You can shim the bearings to remove the slop.

Have you done this? Are you suggesting the shims go in the pocket(s) of the housing before installing the bearings? Do you recommend doing this for both bearings equally (of course, without creating binding)?

 

[stiles]

I had the same problem and put 2 shims in and it helped. Still a little play which I think it must need but far less than it had. Mine was actually rubbing against the housing and wearing it down. I contacted horizon and they sent a new spur gear and housing. Customer service is really good. Maybe hit them up and see if they will send the shims

 

[RCBro80]

I had the same problem and put 2 shims in and it helped. Still a little play which I think it must need but far less than it had. Mine was actually rubbing against the housing and wearing it down. I contacted horizon and they sent a new spur gear and housing. Customer service is really good. Maybe hit them up and see if they will send the shims

Not sure if they'll have shims since they're not included in the kits.. and I am upgrading a Mega so all of the BLX parts are from Jenny's.

Definitely not a huge deal.. shims are cheap and easy to get (one day I'm going to try making my own... we have sheet metal punch equipment at work... but I have a feeling it won't be pretty).

 

[Camaroboy383]

The rubbing is usually from foreign debris entering the module.. not the slipper itself... the tolerance is close, add sand/ dirt and viola rub fest...

They can be shimmed if you want to, definitely no harm in that... (I've personally never shimmed one on any of my rigs) The more important part imo is sealing the module to prevent debris egress, which will typically prevent the rubbing..

 

[RCBro80]

The rubbing is usually from foreign debris entering the module.. not the slipper itself... the tolerance is close, add sand/ dirt and viola rub fest...

They can be shimmed if you want to, definitely no harm in that... (I've personally never shimmed one on any of my rigs) The more important part imo is sealing the module to prevent debris egress, which will typically prevent the rubbing..

Makes sense. Any recommendations on sealing the module? Does the dirt tend to come in via the motor mounting slots, the bearings, or the housing joint itself?

 

[Camaroboy383]

The main section to be sealed is the bottom opening of the module around the spur.. I use 3m double sided tape and cut strips to fit nicely around the spur opening.. I leave the protective film on the tape on the bottom side so it will slide on the chassis while installing the module.. I'll see if I can find that thread for you..
https://www.arrmaforum.com/threads/help-me-upgrade-my-senton-3s-for-sand.20322/

 

[RCBro80]

The main section to be sealed is the bottom opening of the module around the spur.. I use 3m double sided tape and cut strips to fit nicely around the spur opening.. I leave the protective film on the tape on the bottom side so it will slide on the chassis while installing the module.. I'll see if I can find that thread for you..
https://www.arrmaforum.com/threads/help-me-upgrade-my-senton-3s-for-sand.20322/

Awesome, thanks! I'll try that for sure