Kraton What made this happen to the pinion?

[Calabash]

I've never seen a pinion ground down like this. Does anyone know what happened?

 

[Garcbomber]

Those are cheap soft , bought a set of 3 or 5 incremental teeth sizes for an infraction when I first started running hobby grade 6S rigs last year. First one looked like that after the initial bash with a weak RTR on-road infraction. Never again, arrma D-safe are worth their tag but still have limitations with high RPM/torque motors.

What does the spur look like, probably rounded enough of a radii on the tooth peaks rendering it useless as well.

 

[Diem Turner]

Either material failure, some fierce binding either at the center diff or somewhere behind it, or some combination of the two. Since your pinion is toast, now's a good time to give the rest of your drivetrain a good once over to ensure that everything is running smoothly, without binding anywhere. If everything else turns easily, replace the pinion with something of higher quality and carry on. If something's binding, get that taken care of.

Here's a good selection of Powerhobby, IslandHobbyNut and SAGA gears for 5mm shafts.
https://www.islandhobbynut.com/shop?page=2

 

[Fishtank]

that’s crazy picture of the spur?

 

[Calabash]

Thank you both!

that’s crazy picture of the spur?

Have not taken it out yet.

 

[ChemEng]

Thank you both!

Have not taken it out yet.

View attachment 293638

Check the spur/driveline before making an order…

Wound suck to pay for shipping more than once!

 

[Garcbomber]

Had the same softness issue with their 40T spur initially.

Sent me a replacement, that one failed even worse. Thin

 

[ArrmaFreek2022]

I've never seen a pinion ground down like this. Does anyone know what happened?View attachment 293606View attachment 293607View attachment 293608

It is the extreme power of the Kraton combined with a bad mesh? Wow I never seen anythingn like that either, is that aluminum?

 

[Calabash]

It is the extreme power of the Kraton combined with a bad mesh? Wow I never seen anythingn like that either, is that aluminum?

It was advertised as "steel" It ran well for awhile there then this, might have been bad mesh...

Check the spur/driveline before making an order…

Wound suck to pay for shipping more than once!

Thanks, I have a back up already.

 

[Hector_Fisher]

Last time that happened to me, the pinion grub screw had come out and got wedged between the pinion and the spur. I think one gear "grabbed" the grub screw and the other kept spinning. The rest is history. As was my wallet.

 

[SrC]

Those are cheap soft , bought a set of 3 or 5 incremental teeth sizes for an infraction when I first started running hobby grade 6S rigs last year. First one looked like that after the initial bash with a weak RTR on-road infraction. Never again, arrma D-safe are worth their tag but still have limitations with high RPM/torque motors.

What does the spur look like, probably rounded enough of a radii on the tooth peaks rendering it useless as well.

+1
I find the Safe-D pinuions to be absolute crap. You can buy some from JennysRC for like $3.00 a pair. They are not even worth the $3.00. Don't do it. Spend the coin on Tekno's. Don't cheap out on pinions. It's a critical part of the hobby if you are serious about your rigs. FWIW, I noticed the spur gear on mine was in perfect shape. That tells me the Stocker pinions are soft cheap RTR JUNK!!!! And toss the crush sleeve and clip while you are at it. Useless liability if anything.
I said it before. Trust me on this.

 

[Garcbomber]

+1
I find the Safe-D pinuions to be absolute crap. You can buy some from JennysRC for like $3.00 a pair. They are not even worth the $3.00. Don't do it. Spend the coin on Tekno's. Don't cheap out on pinions. It's a critical part of the hobby if you are serious about your rigs. FWIW, I noticed the spur gear on mine was in perfect shape. That tells me the Stocker pinions are soft cheap RTR JUNK!!!! And toss the crush sleeve and clip while you are at it. Useless liability if anything.
I said it before. Trust me on this.

Safe-D pinion went 4.22 0-60mph on grass, it’s fine for 99.9 percent of these guys

 

[SrC]

^^^ Yeah and for how long will they last?
One video and one pass? A supposed record?
I think you missed my point altogether?
Or maybe I missed your point?

 

[Garcbomber]

I can’t give you a mileage, but my dedicated 6000 mah G+ CNHL is cycled through and now high ohm. Robinson racing pinions/spur didn’t last a pack…

As a material process engineer, I know hardness and treat can have tolerances along with anything. Arrma isn’t some mom and pop shop doing zero research and development unlike Traxxas and their “alloy”

 

[SrC]

Arrma has much RTR garbage parts out the box. The little things are cheap to keep the price point low for sales and their bottom line up. Including their Safe-D pinions as of late. Outsourced China stuff. Arrma does not make pinions. QC is non existent in China. And HH can't effectively control that. Is what it is. Arrma is still a great product Overall. The little things need to be upgraded for very obvious reasons. That's all.

 

[ChemEng]

are there any "good" D-pinions? I really like the concept as i have terrible luck with grub screws on normal pinions (even with locktite. The safe-d pinions work great, but they are a bit soft.