Drive Gear Questions for Novice

[slothRC]

Hello all. I am new to the forum as of today, and I am happy to have access to the incredible wealth of knowledge and experience here.

I purchased a Team Associated CR12, which was delivered last Saturday, and pretty quickly started hearing grinding noises coming from the truck while the drive motor was activated. I finally took it all apart today and found that the 12t gear on what Associated Electrics calls the "step gear" is stripped.

I run this thing in creeks a lot, which I believe has something to do with the damage, so I would like to replace all drive gears with metal drive gears if possible and not terribly expensive, but I am not sure exactly how to determine compatibility. I'll post pics of the truck (for fun), the stripped part, and the AE replacement parts that I would like to find metal versions of. Specs (as determined by me, a guy who doesn't know what he's doing): 56t "main drive gear"; 12t to 33t "step gear".

I would be very happy to receive recommendations on metal replacement parts. Please forgive my lack of specific knowledge on these things; when replying, please try to give as much detail as possible so that I can learn. I'm mechanically minded (former 10+ year bicycle mechanic), but have had zero experience with RC before I bought this CR12.

"Step Gear", AE part # 41041:
https://www.associatedelectrics.com/...r12_step_gear/
"Main Drive Gear", part # 41035:
https://www.associatedelectrics.com/...in_drive_gear/
Stripped "Step Gear":

CR12 Toyota FJ45:

[JatoTheRipper]

Welcome to the site!

The photos are too large for this site as the maximum allowable size is 1200x1200.

Besides that, do you know the pitch of these gears? I'm not familiar with the CR-12. Knowing the pitch would go a long way in possibly finding other gears.

[slothRC]

Originally Posted by JatoTheRipper

Welcome to the site!

The photos are too large for this site as the maximum allowable size is 1200x1200.

Besides that, do you know the pitch of these gears? I'm not familiar with the CR-12. Knowing the pitch would go a long way in possibly finding other gears.

Thanks for the welcome and the tip about image size! I edited it to links. I'll get out my calipers and do some measuring and get back about the pitch.

[JatoTheRipper]

Originally Posted by slothRC

Thanks for the welcome and the tip about image size! I edited it to links. I'll get out my calipers and do some measuring and get back about the pitch.

Sadly, your photos aren't showing for me now. Google Photos is a highly unreliable photo host for some reason. I recommend Imgur for a completely free option.

[k7zpj]

Please continue to work on being able to post pictures. With a CR12 you will need that skill set.

The metal transmission gears for the Thunder Tiger Kaiser will work as a replacement for the CR12. Unfortunately they are really hard to find right now.

https://www.gpmparts.com/thunder-tig...-90079983.html


I would contact Team Associated and ask for replacement gears so you can get your rig running again. This is a pretty common problem with the CR12.

Here is the video I used when I rebuilt a CR12 belonging to a friend of mine:

[slothRC]

Originally Posted by k7zpj

Please continue to work on being able to post pictures. With a CR12 you will need that skill set.

The metal transmission gears for the Thunder Tiger Kaiser will work as a replacement for the CR12. Unfortunately they are really hard to find right now.

https://www.gpmparts.com/thunder-tig...-90079983.html


I would contact Team Associated and ask for replacement gears so you can get your rig running again. This is a pretty common problem with the CR12.

Here is the video I used when I rebuilt a CR12 belonging to a friend of mine:

I fixed the pictures! They should be displaying now.

I found that video as well and found it very helpful, so thanks for posting that. I also just received an email from AE about the parts. They directed me to their RMA area to get my replacement parts from them, and they also recommended the GPM metal parts as a more durable replacement. Seeing as how the GPM replacements are out of stock everywhere, I am wondering if there are alternative options. I'm also a little nervous because the AE website shows even the stock replacement parts are out of stock.

Originally Posted by JatoTheRipper

Sadly, your photos aren't showing for me now. Google Photos is a highly unreliable photo host for some reason. I recommend Imgur for a completely free option.

I took your tip on Imgur and it looks like the photos are showing up now, thanks!

This is a bit rough because I'm not sure how much material was removed from the gears due to damage before measuring, but here's what I got for gear pitches (FYI, the "step gear" consists of the 12t and 33t):
12t: 37 or 38 pitch
33t: 40 pitch
56t: 41 pitch

FYI, wrong area I know, but just in case anyone is interested, here's a video I shot of the CR12 before it was out of commission. You can actually hear the pre-failure grinding noise in one of the shots (1:31):
https://youtu.be/MKXaACDmjk0

[Mattmann23]

I 3D scanned and reverse engineered this gear and have 3D printed it and it does work..

The small gear pitch is what i an trying to confirm

https://www.dropbox.com/sh/oi51cyl89...pkyiMcv1a?dl=0

STL file is here as well.

All gears need the same diametrical pitch...

[Voodoobrew]

Note to self: When looking for a new vehicle and replacement parts are listed as "hot item" > autocorrect to "fails often".