Kraton New V4 Kraton Noob & Set Screw Issue

[enginerdkraton]

Hey all! Relatively new here. I recently upgraded from a brushless converted Senton Mega to a Kraton 6s. It’s safe to say they’re a bit different. However, I took the Kraton out for a very light bash (max 4 ft jump) and the pinion already came loose and the set screw was nearly crushed by the spur gear. Luckily I was able to get it out and get the pinion gear off. So I have 2 questions:

1. Is this a normal occurrence of the pinion gear not being tight enough? Or did I miss something and should have tightened it down when I first got it?

2. Are the set/grub screws something you can pick up at your local Lowe’s/Home Depot? Or are they RC car/Arrma specific?

keep in mind I’m extremely new to the hobby and ready to learn! Thanks in advance

 

[DoNoHarm]

Set screws are a very specific item... can’t find it at any modern hardware store. On top of that, many pinions have a different thread pitch so many grub screws don’t work on other pinions. I think the kraton 6s comes with an optional pinion and has a grub screw for it? You can just use that one.

That’s not a normal occurrence but when you buy an RTR, you should go over all the screws and make sure they’re tight before driving it. Make sure you use some blue loctite when installing the new pinion grub screw. Welcome to the club man. Love arrma vehicles... over this whole hobby’s existence they definitely can be considered one of the best brands ever, which is impressive because they’re so new.

 

[NewSensei]

Hey all! Relatively new here. I recently upgraded from a brushless converted Senton Mega to a Kraton 6s. It’s safe to say they’re a bit different. However, I took the Kraton out for a very light bash (max 4 ft jump) and the pinion already came loose and the set screw was nearly crushed by the spur gear. Luckily I was able to get it out and get the pinion gear off. So I have 2 questions:

1. Is this a normal occurrence of the pinion gear not being tight enough? Or did I miss something and should have tightened it down when I first got it?

2. Are the set/grub screws something you can pick up at your local Lowe’s/Home Depot? Or are they RC car/Arrma specific?

keep in mind I’m extremely new to the hobby and ready to learn! Thanks in advance

It is not uncommon sadly. I had this happen on my Senton mega before I went 3s with it. Since then this is what I do with all my pinion gears before the first drive:

All I can tell you is what I do with mine. Take the pinion off, put a small amount of blue locktite on the motor shaft (fine layer) then put the pinion on the shaft, apply locktite to the grub before inserting then make sure the gear is still in a good place and tighten the grub as hard as you can by hand. Do the same on the second grub if you have one

I get pinion gear sets that come with grub screws through Amazon

 

[nino]

Take the set screw off your speed pinion, blue loctite, tighten with a good hex driver, let sit overnight!

 

[DoNoHarm]

It is not uncommon sadly. I had this happen on my Senton mega before I went 3s with it. Since then this is what I do with all my pinion gears before the first drive:

All I can tell you is what I do with mine. Take the pinion off, put a small amount of blue locktite on the motor shaft (fine layer) then put the pinion on the shaft, apply locktite to the grub before inserting then make sure the gear is still in a good place and tighten the grub as hard as you can by hand. Do the same on the second grub if you have one

Hate to nit pick but... don’t tighten it as hard as you can by hand, you’ll strip it right out... just make it snug and turn it till it’s super snug after, basically right until you can feel the wrench yielding.

 

[L3phturn]

Set screws are a very specific item... can’t find it at any modern hardware store. On top of that, many pinions have a different thread pitch so many grub screws don’t work on other pinions. I think the kraton 6s comes with an optional pinion and has a grub screw for it? You can just use that one.

That’s not a normal occurrence but when you buy an RTR, you should go over all the screws and make sure they’re tight before driving it. Make sure you use some blue loctite when installing the new pinion grub screw. Welcome to the club man. Love arrma vehicles... over this whole hobby’s existence they definitely can be considered one of the best brands ever, which is impressive because they’re so new.

Very important that you use blue loctite on the grub screw threads AND let it cure long enough without moving it. Blue thread locker will set initially in about 10 minutes but it takes 24 hours to fully cure. For a moving part like the set screw on the motor shaft that will experience vibration and heat during use, you want to let it cure 24 hours before you run the truck or run the risk of it backing out.

 

[DoNoHarm]

Very important that you use blue loctite on the grub screw threads AND let it cure long enough without moving it. Blue thread locker will set initially in about 10 minutes but it takes 24 hours to fully cure. For a moving part like the set screw on the motor shaft that will experience vibration and heat during use, you want to let it cure 24 hours before you run the truck or run the risk of it backing out.

This. Always wait the 24 hours. So far every single time that I try and cut it close, it comes loose.

 

[NewSensei]

Hate to nit pick but... don’t tighten it as hard as you can by hand, you’ll strip it right out... just make it snug and turn it till it’s super snug after, basically right until you can feel the wrench yielding.

True, I forget to add the "you'll feel it when you shouldn't push further...it comes so naturally these days

 

[DoNoHarm]

True, I forget to add the "you'll feel it when you shouldn't push further...it comes so naturally these days

Yeah lol. I didn’t wanna pick apart ur post but he’s kinda new so u gotta remind these things

 

[NewSensei]

This. Always wait the 24 hours. So far every single time that I try and cut it close, it comes loose.

Yeah, agreed, the cure time is very important.

Yeah lol. I didn’t wanna pick apart ur post but he’s kinda new so u gotta remind these things

It's all good, normally add that and to wait a day before using...getting sloppy in my old age

 

[Rcproponent]

I thought the 24 hour thing was silly when I first started. Now I know. I got away with it a time or two... but not for any length of time lol. Got maybe a bash or not even out of it and ziiiiiiiiiing ... AHHH CRAP! The dreaded noise of no pinion engagement lol.

24 hours is key ??

 

[DoNoHarm]

I thought the 24 hour thing was silly when I first started. Now I know. I got away with it a time or two... but not for any length of time lol. Got maybe a bash or not even out of it and ziiiiiiiiiing ... AHHH CRAP! The dreaded noise of no pinion engagement lol.

24 hours is key ??

Lmao!! “Ziiing... ahhh, crap!” ?? that’s facts dude

 

[Notorious J]

Hey all! Relatively new here. I recently upgraded from a brushless converted Senton Mega to a Kraton 6s. It’s safe to say they’re a bit different. However, I took the Kraton out for a very light bash (max 4 ft jump) and the pinion already came loose and the set screw was nearly crushed by the spur gear. Luckily I was able to get it out and get the pinion gear off. So I have 2 questions:

1. Is this a normal occurrence of the pinion gear not being tight enough? Or did I miss something and should have tightened it down when I first got it?

2. Are the set/grub screws something you can pick up at your local Lowe’s/Home Depot? Or are they RC car/Arrma specific?

keep in mind I’m extremely new to the hobby and ready to learn! Thanks in advance

Everyone here says blue (medium) thread lock. I use a small drop of red (hard). Curing time is very important too. The reason I use red here, is the heat generated by the mesh of the pinion and spur could/has been enough to break down the medium thread lock. When the time comes that I need to change the pinion, I just use a mini torch to heat up the screw, and use my best driver in the tool box to break it free. Haven't toasted a grub screw in a long time using this method.

 

[NewSensei]

Everyone here says blue (medium) thread lock. I use a small drop of red (hard). Curing time is very important too. The reason I use red here, is the heat generated by the mesh of the pinion and spur could/has been enough to break down the medium thread lock. When the time comes that I need to change the pinion, I just use a mini torch to heat up the screw, and use my best driver in the tool box to break it free. Haven't toasted a grub screw in a long time using this method.

I tried the red, was a bit of a bear to get off on more than one occasion, especially when it was cold and had been on there a month or so, hard to get hot and keep it that way when it's 20°f outside . That's why I started putting some blue on the shaft directly, seems to do the trick. I haven't had one come off since that first factory pinion.

 

[Rcproponent]

Everyone here says blue (medium) thread lock. I use a small drop of red (hard). Curing time is very important too. The reason I use red here, is the heat generated by the mesh of the pinion and spur could/has been enough to break down the medium thread lock. When the time comes that I need to change the pinion, I just use a mini torch to heat up the screw, and use my best driver in the tool box to break it free. Haven't toasted a grub screw in a long time using this method.

I tried the red, was a bit of a bear to get off on more than one occasion, especially when it was cold and had been on there a month or so, hard to get hot and keep it that way when it's 20°f outside . That's why I started putting some blue on the shaft directly, seems to do the trick. I haven't had one come off since that first factory pinion.

Try some permetex orange thread locker. Holds like red, but when you goto take it off, it cracks open like blue. ??

 

[enginerdkraton]

Thank you guys! Overwhelming responses overnight, love it! Just ordered a pinion and set screw from Arrma along with some Locktite. I’m looking forward to getting more into the hobby!!!

 

[arrmadillo]

Like said above, these new rigs should be checked for all fasteners tight before you run. Pinion mesh is one of the 1st things I check for, reset and loctite.