Cheap RC car stripped gears
12-07-2020, 04:33 AM
#1
Cheap RC car stripped gears
G'day everyone.
Just recently purchased a HPI Maverick Phantom XT (out of box specs below) and both the kids and I have enjoyed our first "proper" RC car but the last session resulted in lots of grinding noises and not much in the way or forward movement. Upon returning home and opening up the car I found a stripped motor gear and spur gear on the centre shaft. While I suspect the damage may have come from sand ingress I am not experienced enough to be sure and was also a bit confused by the grease in the front and rear diffs but not between these two gears. I would be very grateful for some insight from a more experienced RC hobbyist than me. My thinking is that I first wanted to make sure this isn't a manufacturing problem before making the repairs especially since I am upgrading the battery and charger too. Also while the parts are cheap it will cost me some time to replace the bigger centre shaft gear. Finally, if it is likely caused by sand getting in and not lack of lubrication or poor assembly tolerances then any suggestions on how to prevent this in future would be fab.
MM-550 brushed motor
MRX-244 receiver
MS-06WR steering servo
MSC-30BR-WP controller
1800mAh Ni-MH battery
500mA 4W usb charger
Sorry, can't post photos yet (need 10 posts apparently).
Just recently purchased a HPI Maverick Phantom XT (out of box specs below) and both the kids and I have enjoyed our first "proper" RC car but the last session resulted in lots of grinding noises and not much in the way or forward movement. Upon returning home and opening up the car I found a stripped motor gear and spur gear on the centre shaft. While I suspect the damage may have come from sand ingress I am not experienced enough to be sure and was also a bit confused by the grease in the front and rear diffs but not between these two gears. I would be very grateful for some insight from a more experienced RC hobbyist than me. My thinking is that I first wanted to make sure this isn't a manufacturing problem before making the repairs especially since I am upgrading the battery and charger too. Also while the parts are cheap it will cost me some time to replace the bigger centre shaft gear. Finally, if it is likely caused by sand getting in and not lack of lubrication or poor assembly tolerances then any suggestions on how to prevent this in future would be fab.
MM-550 brushed motor
MRX-244 receiver
MS-06WR steering servo
MSC-30BR-WP controller
1800mAh Ni-MH battery
500mA 4W usb charger
Sorry, can't post photos yet (need 10 posts apparently).
12-07-2020, 01:51 PM
#2
I suppose I should also add that the car has had some altercations with solid objects as you might expect for novice drivers. Thinking about it overnight I wondered if that kind of shock load on the drivetrain is perhaps the more obvious answer for the stripped gears?
The only other bit of information that I thought is relevant is that while there was sand around the motor area there was none that I could see inside the case containing the two gears, just the debris from the munched gears which in my mind at least makes the above explanation more and more obvious...
The only other bit of information that I thought is relevant is that while there was sand around the motor area there was none that I could see inside the case containing the two gears, just the debris from the munched gears which in my mind at least makes the above explanation more and more obvious...
12-07-2020, 08:33 PM
#3
Im guessing its a plastic spur thats gone . No need to lube , it just promotes gunk sticking to your gears .
Bad Gear Mesh will damage gears .
As well as small objects getting in the gears .A loose motor or motor mount , or even a bent drive shaft ( from impacts ) can ruin your mesh .
Sometimes they just go from repeated shock . Fast launches and grippy tires .
The spur can sort of be sacrificial sometimes .
Usually easy to change , and saves you diving deeper into the cars diffs .
Buy 2 .
Bad Gear Mesh will damage gears .
As well as small objects getting in the gears .A loose motor or motor mount , or even a bent drive shaft ( from impacts ) can ruin your mesh .
Sometimes they just go from repeated shock . Fast launches and grippy tires .
The spur can sort of be sacrificial sometimes .
Usually easy to change , and saves you diving deeper into the cars diffs .
Buy 2 .
12-08-2020, 06:14 PM
#4
Thanks for the reply, really appreciated.
I will have to check the mesh once the replacement parts arrive and I have fitted them. In talking with a local RC guy he suggested that we should also lay off the trigger when jumping the car so the drivetrain doesn't spin up to a million and then suddenly come to a dead stop upon landing so with that bit of advise and staying away from trees I at least have some faith that the new gears will last a little longer! I couldn't get more than one of each gear as they were low on stock but will definitely be ordering a couple of spares as soon as they are available again. I am also really looking forward to having the new Lipo battery so we can run the car for more than 10 minutes!
I will have to check the mesh once the replacement parts arrive and I have fitted them. In talking with a local RC guy he suggested that we should also lay off the trigger when jumping the car so the drivetrain doesn't spin up to a million and then suddenly come to a dead stop upon landing so with that bit of advise and staying away from trees I at least have some faith that the new gears will last a little longer! I couldn't get more than one of each gear as they were low on stock but will definitely be ordering a couple of spares as soon as they are available again. I am also really looking forward to having the new Lipo battery so we can run the car for more than 10 minutes!
