Senton Pinion screw stripped

[1999fd]

Even with thread locker the pinion screw got eaten up why? What should I do?

 

[Moonstonemike]

Even with thread locker the pinion screw got eaten up why? What should I do?
View attachment 224244

Are you using stock spur gear or a metal one?

 

[1999fd]

Are you using stock spur gear or a metal one?

Stock one

 

[Velodromed]

Even with thread locker the pinion screw got eaten up why? What should I do?
View attachment 224244

Not quite sure what you mean. The grub screw fell out and got caught between the Spurs and pinion? Or something else?

If you’re having issues with the grub screw staying tight you need to thoroughly clean the grub screw with alcohol or brake cleaner as well as the grub screw hole in the pinion. Most screws are covered with an oily substance from manufacturing. You’ve got to get that off or the Loctite simply won’t stick.

I also use longer grub screws. I use 5mm 12.9 tool steel ‘flat tip’ grub screws. The longer grub gives more for the hex to grab onto and the flat tip has more contact with the motor shaft than the typical cup tip that most grub screws have.

 

[1999fd]

Not quite sure what you mean. The grub screw fell out and got caught between the Spurs and pinion? Or something else?

If you’re having issues with the grub screw staying tight you need to thoroughly clean the grub screw with alcohol or brake cleaner as well as the grub screw hole in the pinion. Most screws are covered with an oily substance from manufacturing. You’ve got to get that off or the Loctite simply won’t stick.

I also use longer grub screws. I use 5mm 12.9 tool steel ‘flat tip’ grub screws. The longer grub gives more for the hex to grab onto and the flat tip has more contact with the motor shaft than the typical cup tip that most grub screws have.

View attachment 224252

It didn't fall out it got eaten up while on the pinion. Do I just add locktite to the pinion without the screw? It worked for me once

 

[Velodromed]

It didn't fall out it got eaten up while on the pinion. Do I just add locktite to the pinion without the screw? It worked for me once

I don’t get how that happened, the stock grub screw is mostly buried in the pinion. Did it come loose allowing the pinion to shift? But even if it did the spur wouldn’t reach it…unless the motor shifted in the mount pushing them closer. Even then it would more likely chew the plastic spur up before hurting the metal grub. I don’t think I’m understanding what happened lol.

Yes, a little extra locktite on the motor shaft could help the pinion purchase but shouldn’t be the main connection. That’s the grub screws job.

 

[SrC]

Locktite is NOT a Glue If that is what you mean and used as a substitute for a setcrew/Grub Screw. NEED the setscrew there!!
Maybe I misunderstood you???? If the Set screw backed out and got chewed up, it was probably user error.
Sets crews are consumable parts and you should have spares around. Cheap enough. Just part of RC.
Set screws need to be cleaned well in a solvent like @Velodromed stated. Clean the Pinion also. Only use a quality Hex driver.
And not "L" wrenches. No reason to use Loctite on the Motor's shaft at all, if done correctly. You might have a very hard time removing the Pinion next time. Loctite is for Metal Screw Threads. Use Heat before attempting to wrench any metal on metal screws that have Thread locker on it. Most do from the factory Assy.

I use Loctite 243 Blue. It is oil friendly. But still always clean the screws.

 

[Moonstonemike]

I think there may be confusion because of the wording. To clarify the pinion is the gear in the picture. The grub screw is the screw that holds the pinion on motor shaft.

So is it the pinion or grub screw that is getting chewed up?

Also Make sure the pinion and spur gear are the same pitch or it will not mesh properly.

 

[Velodromed]

I think there may be confusion because of the wording. To clarify the pinion is the gear in the picture. The grub screw is the screw that holds the pinion on motor shaft.

So is it the pinion or grub screw that is getting chewed up?

He’s calling it the ‘pinion screw’ so pretty sure he’s referring to the grub…but yeah, that’s a good point to clarify.

 

[Moonstonemike]

It looks like your pinion gear is worn but also looks like it may be pulled off the shaft. It's hard to tell from picture but it looks like it's the D shaped hole. So even if grub screw came off it should still run but would probably slide in towards the motor. There should also be a clip on the end of the shaft to keep the pinion from coming off. If your pinion is wearing out as fast as your spur you either have it meshed to tightly or motor mount could also be bent.