Senton 3S BLX spur gear

[Solix]

Hey all and very happy to be here! So I have a Senton 3S BLX and a Big Rock. Love both of them! One day was bashing at the beach and it looks as if one of the bearings in the motor mount blew up, which caused the spur gear assembly to become misaligned. This destroyed my spur gear after a bash session. I'm just sharing this in case this has happened or hasn't yet happened to anyone else. I've been waiting a couple weeks for ARRMA to stock the replacement parts and theres no word when they will. Was wondering if this has happened to anyone else? Also if anyone had used any other compatible parts to replace a spur gear.

 

[Jerry-rigged]

Ouch. Where is the do not like button?

Check the ebay kit breakers, like JRC. Sometimes they have the whole slipper assembly for about $15. But they sell out quick.

 

[JvG]

You are the fifth one i have seen with this problem, including myself. There is something wrong with the gear mesh and way too much dirt getting in the gearbox. Arrma sent me a whole new truck for this issue:

https://www.arrmaforum.com/threads/senton-3s-blx-lost-3-motors.9236/

https://www.arrmaforum.com/threads/big-rock

 

[Bubblehead]

I watched on YouTube where someone recommended putting some Gorilla tape on the bottom of the power module to seal it.

 

[bicketybam]

Looks like the stock cheapo bearing went on the slipper hub and that's what caused the damage to the spur.

 

[Bubblehead]

His recommendation was to keep sand and dirt from getting in, I have ordered replacement bearings.

 

[Solix]

I watched on YouTube where someone recommended putting some Gorilla tape on the bottom of the power module to seal it.

I thing Rich Duperbash did that. ..

 

[Solix]

You are the fifth one i have seen with this problem, including myself. There is something wrong with the gear mesh and way too much dirt getting in the gearbox. Arrma sent me a whole new truck for this issue:

https://www.arrmaforum.com/threads/senton-3s-blx-lost-3-motors.9236/

https://www.arrmaforum.com/threads/big-rock

Who do you contact for that? I have the spur gear on back order but a whole new truck?!?!?!

 

[Jeremy in WI]

Or put a hole in the chassis under the pm to let the sand and dirt out. I've done this on my mega and blx and I haven't had a problem yet.

 

[Wraither92]

Same thing has happened to me 3 times now, I see hot racing makes a steel spur gear but I haven't tried it and am unsure if it actually works.
If anyone has tried said spur gear, can you let us know if it works or not?
In the meantime I have just put some electrical tape over the bottom "breather" hole and the mesh sounds way different than before.
Before with a new gear it would be quiet and after 10 mins of running it it would sound like rocks sloshing around in the power module.
Dirt gets in so fast and chews the spur and the bearings. Really bad design.
After taping it the gears are still quiet after taking it out bashing a bit.

 

[DoNoHarm]

Plastic spurs are always better. A mod1 plastic spur is impossible to strip unless a barrier gets between it and the pinion, which is why I run plastic spurs when possible, because if you use a steel one, it snaps the motor shaft, then you need a new motor. A plastic spur will also strip if the mesh gets messed up. If a steel spur gets out of mesh the pinion usually kills itself.

 

[Wraither92]

That's good logic, I suppose if theres no debris getting in with that monstrous dirt vacuum on the bottom covered than there shouldn't be reason to have a steel spur. Where can I find a mod1 spur for this?

 

[DoNoHarm]

That's good logic, I suppose if theres no debris getting in with that monstrous dirt vacuum on the bottom covered than there shouldn't be reason to have a steel spur. Where can I find a mod1 spur for this?

You can find one if you hunt around, but even with the 32p it won't strip until something goes wrong. If you have a steel 32p spur and something goes wrong, instead of stripping a $5 gear, your do collateral damage. Plastic spur gears never strip unless something is wrong, or the vehicle is being overpowered (ex. Having a 48p spur, putting it into a 3s vehicle, and tightening the slipper all the way down) honestly I see no reason why metal spurs even exist as an option for 10th and 8th scale vehicles because an appropriately pitched plastic gear will never have issues. In space limited environments like arrma's 6s line I can kinda see why, because they can use that super thin metal spur gear because they can't fit a plastic spur that's double the thickness.

 

[jondilly1974]

I just installed the HR metal spur and slipper pads in my Typhon 3S running 4S with 24T/BLX120/2400kv combo out of a 4S Kraton. My plastic spur was never an issue on the stock 15T/BLX100/3200kv setup. Once I upgraded to 24T/BLX120/2400kv and ran on 3S it started to get a little noisy. Put in a 4S pack and it lasted 5 mins.

I’ve also recently rebuilt my diffs because my plan was to run the HR axels, but they were too short for the Typhon front arms. Ended up rebuilding them twice ??‍

Haven’t had a spare moment to get out and run since the diff rebuild. Hoping to find time today, but the wifey usually has other plans in mind. My honey do list is always long.

 

[MacheteMable]

Same thing happened to me except the ball bearings got jammed into the spur and stripped 3 of the teeth. Gonna replace everything with sealed bearings soon, after I get a new axle.

 

[lilzeus]

I've ruined a spur/pinion combo from the dust/dirt in my area, which is VERY heavy. If you watch my vids you'll see what I mean, every landing is a puff of dust and dirt. I had literally just bought all new bearings from a local shop (Revelation Raceway in Montclaire, CA) and took it out to the track. Ran through my 2s battery and then ran the 3s for a few mins. After a chassis slapping landing she was grinding: the yoke melted due to the bearings. Sealed bearings are a must.
Steel vs composite spur: I'm on the fence. A composite spur is $6 shipped. I can go through 5 of those before I pay for 1 steel spur. Plus, the plastic spur is a fail point to save other parts down the line. If I go steel I pass the buck to the next part that will fail and cost to fix almost always goes up along with more issues.
So, with that in mind, its pretty essential to seal off that motor/spur area. I tried the tape. Didn't work and the piece got sucked up into the gears. But now I think I've got a great solution: plumber's putty. With a small sliver of plumber's putty you can seal off the front and back. No worries if any of it gets sucked into gears, its very soft and harmless. Plumber's putty doesn't dry, it stays soft.
You may also noticed I use anti-seize on the slots to make the drive housing easier to remove. She can be tough sometimes.
As you can see, that's also a sealed bearing but that's only sealed on one side. I have Fast Eddy bearings already in it since this photo was taken.
With all that in mind, I'm leaning slightly to sticking with the composite gear over steel.

PS: I've posted pics of the melted yoke here, too.

 

[bicketybam]

I'm on original spurs with my 3s trucks. The driveshafts are another story ?

 

[BeardLadin]

I've ruined a spur/pinion combo from the dust/dirt in my area, which is VERY heavy. If you watch my vids you'll see what I mean, every landing is a puff of dust and dirt. I had literally just bought all new bearings from a local shop (Revelation Raceway in Montclaire, CA) and took it out to the track. Ran through my 2s battery and then ran the 3s for a few mins. After a chassis slapping landing she was grinding: the yoke melted due to the bearings. Sealed bearings are a must.
Steel vs composite spur: I'm on the fence. A composite spur is $6 shipped. I can go through 5 of those before I pay for 1 steel spur. Plus, the plastic spur is a fail point to save other parts down the line. If I go steel I pass the buck to the next part that will fail and cost to fix almost always goes up along with more issues.
So, with that in mind, its pretty essential to seal off that motor/spur area. I tried the tape. Didn't work and the piece got sucked up into the gears. But now I think I've got a great solution: plumber's putty. With a small sliver of plumber's putty you can seal off the front and back. No worries if any of it gets sucked into gears, its very soft and harmless. Plumber's putty doesn't dry, it stays soft.
You may also noticed I use anti-seize on the slots to make the drive housing easier to remove. She can be tough sometimes.
As you can see, that's also a sealed bearing but that's only sealed on one side. I have Fast Eddy bearings already in it since this photo was taken.
With all that in mind, I'm leaning slightly to sticking with the composite gear over steel.
View attachment 41991

PS: I've posted pics of the melted yoke here, too.

So i guess its just a whatever works kinda fix. I was thinking about using RTV.
Would be a pain to remove next time the motor comes out but will it make time between removals longer?

I thought it was pretty silly to leave a gaping hole at the bottom of the gears.

 

[Kdwright85]

I've ruined a spur/pinion combo from the dust/dirt in my area, which is VERY heavy. If you watch my vids you'll see what I mean, every landing is a puff of dust and dirt. I had literally just bought all new bearings from a local shop (Revelation Raceway in Montclaire, CA) and took it out to the track. Ran through my 2s battery and then ran the 3s for a few mins. After a chassis slapping landing she was grinding: the yoke melted due to the bearings. Sealed bearings are a must.
Steel vs composite spur: I'm on the fence. A composite spur is $6 shipped. I can go through 5 of those before I pay for 1 steel spur. Plus, the plastic spur is a fail point to save other parts down the line. If I go steel I pass the buck to the next part that will fail and cost to fix almost always goes up along with more issues.
So, with that in mind, its pretty essential to seal off that motor/spur area. I tried the tape. Didn't work and the piece got sucked up into the gears. But now I think I've got a great solution: plumber's putty. With a small sliver of plumber's putty you can seal off the front and back. No worries if any of it gets sucked into gears, its very soft and harmless. Plumber's putty doesn't dry, it stays soft.
You may also noticed I use anti-seize on the slots to make the drive housing easier to remove. She can be tough sometimes.
As you can see, that's also a sealed bearing but that's only sealed on one side. I have Fast Eddy bearings already in it since this photo was taken.
With all that in mind, I'm leaning slightly to sticking with the composite gear over steel.
View attachment 41991

PS: I've posted pics of the melted yoke here, too.

Thanks for the info about the plumbers putty! Do you think that silicone or polly urethane caulk would work to?

 

[jondilly1974]

If you want something that is easy to clean off, makes an air tight seal, and is cheap, look for duct seal. It’s a durable grey putty that is a few bucks at any hardware store.