Kraton How to remove pinion set screw?

[RickTheSlick]

Hello everyone,

I am very new in the RC world. And had make some mistakes while maintenance of the car...

Now, when I would remove 12T pinion, I did fail and did broke the lock screw... any tips how I can remove this one?

//Rickard

 

[unclebrudy]

I carefully drilled mine out, extremely slowly so as not to mar the shaft. You can also Dremel a slot and then use a flathead, but you may ruin the pinion. Depending on how stripped it is, you may be able to jam a thick rubber band in there and try to grip it with your driver. I’ve also read some people superglue a spare driver in there and then try to extract. In all cases you should use a butane torch or soldering iron to heat up the grub screw decently hot.

Fortunately pinions are very affordable so if you’re set on swapping pinions those are a few ways you can try.

 

[SrC]

Should have heated the Pinion up, before using a quality hex driver. You can drill it out. Pinion will be bricked. Try not to over drill and ruin the motors armature shaft. Replace with new pinion. Threadlock the new set screw. Wait 24 hours for the TL to set before you run it again. I would recommend Tekno Mod 1 pinions as replacements if you don't already have spare pinions.

 

[jondilly1974]

Your only hope now is to carefully drill that baby out a little at a time. Start with a small bit and step up until you can pull the pinion off. The heat from drilling should loosen any thread lock holding it on, but if not, use a hot soldering iron to heat it for a few mins and then yank.

 

[SrC]

I never had luck with saving the pinion by drilling the one time this happened to me. I even heated it up prior. But the Arrma Gorrilla Snot for TL that they used caught me blindsided. Pinions are cheap enough though. Its worth trying to save it if in decent shape.
I feel that sometimes you have to heat up the set screw so hot that the metal softens to the point that the hex strips easier.
I use MIP drivers.

 

[RickTheSlick]

I do not care about the pinion. I just don't want to ruin the start... If I would do that, is it possible to repair the motor?

 

[jondilly1974]

I do not care about the pinion. I just don't want to ruin the start... If I would do that, is it possible to repair the motor?

These motors are too cheap to repair. A new one is like $60 from JRC

 

[bicketybam]

I do not care about the pinion. I just don't want to ruin the start... If I would do that, is it possible to repair the motor?

I've drilled out plenty and never have ruined the motor. You'll be fine ?

 

[RickTheSlick]

These motors are too cheap to repair. A new one is like $60 from JRC

I do live in Sweden, and we have to pay around 140 dollars. Its like 20% of the car...

 

[DoNoHarm]

Sadly you can’t repair these motors. Rebuild kits haven’t been a thing since the early 2010’s.

 

[RickTheSlick]

Sadly you can’t repair these motors. Rebuild kits haven’t been a thing since the early 2010’s.

What kind of failure is possible? To destroy the shaft or what? As I said before, the pinion I do not care about.

 

[DoNoHarm]

What kind of failure is possible? To destroy the shaft or what? As I said before, the pinion I do not care about.

Yes. If you destroy the shaft, gotta get a new motor. Rotors/ shafts haven’t been available for years because it was so cheap for people to repair motors that the companies weren’t making much money. Just drill carefully and make sure you stop drilling once you’re completely through the set screw.

 

[SrC]

yeah, just drill it out. Don't go deep. slow steady pressure till the drill bit hits the armature's "flat". I doubt you will ruin the arm that way. It is much harder steel than the pinion and set screw. You don't have a choice. You must drill it out. Everyone does this. It may be easier to mount the motor in a jig or soft vice for drilling. I can do it in my hand. It will drill out very fast .IMO. So, slow steady pressure. Your drilling depth is only about 4 mm. Its not hard. Don't be surprised if the pinion doesn't slide right off the Armature immediately afterwards. It needs to be yanked or pulled off. The pinion is snug on the shaft and the old Arrma threadlocker also keeps it stuck onto the armature. Arrma uses a lot of the Red TL there. Reinstall set screw and new pinion using Blue TL.

 

[LibertyMKiii]

MIP hex tools

 

[RickTheSlick]

yeah, just drill it out. Don't go deep. slow steady pressure till the drill bit hits the armature's "flat". I doubt you will ruin the arm that way. It is much harder steel than the pinion and set screw. You don't have a choice. You must drill it out. Everyone does this. It may be easier to mount the motor in a jig or soft vice for drilling. I can do it in my hand. It will drill out very fast .IMO. So, slow steady pressure. Your drilling depth is only about 4 mm. Its not hard. Don't be surprised if the pinion doesn't slide right off the Armature immediately afterwards. It needs to be yanked or pulled off. The pinion is snug on the shaft and the old Arrma threadlocker also keeps it stuck onto the armature. Arrma uses a lot of the Red TL there. Reinstall set screw and new pinion using Blue TL.

Which drill works best? Its 4mm screw right? 3 mm drill? 2 mm drill?

 

[SrC]

I believe the setscrew is 4mm by 4mm. Start smaller and work your way larger. Like stated above by @jondilly1974 .

 

[jkflow]

Apply heat first, soldering iron or torch to break the thread locker seal. Then drill baby drill

 

[Ohiodrz400sm]

yeah, just drill it out. Don't go deep. slow steady pressure till the drill bit hits the armature's "flat". I doubt you will ruin the arm that way. It is much harder steel than the pinion and set screw. You don't have a choice. You must drill it out. Everyone does this. It may be easier to mount the motor in a jig or soft vice for drilling. I can do it in my hand. It will drill out very fast .IMO. So, slow steady pressure. Your drilling depth is only about 4 mm. Its not hard. Don't be surprised if the pinion doesn't slide right off the Armature immediately afterwards. It needs to be yanked or pulled off. The pinion is snug on the shaft and the old Arrma threadlocker also keeps it stuck onto the armature. Arrma uses a lot of the Red TL there. Reinstall set screw and new pinion using Blue TL.

Plus 1.

My pinion had red loctite on the shaft as well .

 

[SrC]

The heat generated by the drill bit should suffice. I would not expect to salvage the pinion. Op's looks worn out in the picture.

 

[RickTheSlick]

Maybe hard to see, but am I through yet?