RC10 - A Stamp Rebuild - Chipped Idler Gear

[MarkyDents]

If your going for the stock look go with the white spur with the big ole’ teeth

[GreenBar0n]

I wouldn't put a 64 pitch gear on a 6 gear transmission. The spur wobble will likely trash it.

64 pitch gears are good for clean carpet / on road driving, but are less durable for any rough surface driving. Whichever spur you choose, put diff balls in it.

The white gear is stock, right? I had thought these were dirt geared for racing, out of the box. Surprised to hear the gears it came with aren't ideal, or even good for dirt.

If your going for the stock look go with the white spur with the big ole’ teeth

Tough choice, it did look good with the black gear, but wasn't sure if that was the better choice for grass and dirt. Black gear says 108 on it.

[Frankentruck]

The white 32 pitch gear is what it came with stock. The black 64 pitch gear and the foam tires are not original equipment from AE. An owner can customize/accessorize as desired for intended use, as was previously done with that buggy.

[XLR8]

I think 64dp gears are fine for relatively low power 1/12 pan car but I'd never run them in anything more powerful or heavy. Those tiny teeth don't offer a lot of shear strength.
To keep your RC10 original and reliable, you'll want to use the white 32dp spur gear.
For the differential to function, you'll need to pack the spur with balls and use the appropriate "diff grease". Using ordinary grease will cause the diff to slip.

[GreenBar0n]

I think 64dp gears are fine for relatively low power 1/12 pan car but I'd never run them in anything more powerful or heavy. Those tiny teeth don't offer a lot of sheer strength.
To keep your RC10 original and reliable, you'll want to use the white 32dp spur gear.
For the differential to function, you'll need to pack the spur with balls and use the appropriate "diff grease". Using ordinary grease will cause the diff to slip.

Now I've got it, on the white gear the number said 64, the black gear 108, I was not familiar with term or concept of diametral pitch, always had referred to them by tooth count in the past.

Thanks guys!

[XLR8]

... I was not familiar with term or concept of diametral pitch, always had referred to them by tooth count in the past.

I apologize for not making it clear in my earlier comment.

There's an inverse relationship between diametral pitch (dp) and the actual size of the tooth. Thus, 32dp is a large tooth and 64dp is small.

With early RC10's like yours, all gears (including internal gears) are 32dp. For the Stealth era cars, AE switched all gears to 48dp. These 48dp gears, as the number might suggest, have a tooth size mid-way between 32dp and 64dp. I reckon 48dp is a compromise between high efficiency (64dp) and high strength (32dp).

Anyway, with the modern re-released RC10's, AE switched the spur and pinion to 48dp but retained 32dp for internal gears in 6-gear trans. You will see this when your 40th car arrives.

[Dangeruss]

well put. Swapping six gear transmissions to 48 pitch pinion/spurs for off-road racing was also a thing back in the day.

Previous owner looked like he came from the on-road/carpet world... foam tires, 64 pitch gearing, locked diff, etc... maybe his local carpet track built some ramps to bring in more business.

For a Hasley build, definitely the 32 pitch pinion and white spur with a functioning diff. Breaking out a drill and going full Hasley is optional...

[XLR8]

well put. Swapping six gear transmissions to 48 pitch pinion/spurs for off-road racing was also a thing back in the day.

Previous owner looked like he came from the on-road/carpet world... foam tires, 64 pitch gearing, locked diff, etc... maybe his local carpet track built some ramps to bring in more business.

For a Hasley build, definitely the 32 pitch pinion and white spur with a functioning diff. Breaking out a drill and going full Hasley is optional...

Thanks!
I still have a small collection of Kimbrough and Robinson Racing 48dp spur gears from BITD. More Kimbrough than RR - Kimbrough's were cheaper.

[GreenBar0n]

... I was not familiar with term or concept of diametral pitch, always had referred to them by tooth count in the past.

I apologize for not making it clear in my earlier comment.

There's an inverse relationship between diametral pitch (dp) and the actual size of the tooth. Thus, 32dp is a large tooth and 64dp is small.

With early RC10's like yours, all gears (including internal gears) are 32dp. For the Stealth era cars, AE switched all gears to 48dp. These 48dp gears, as the number might suggest, have a tooth size mid-way between 32dp and 64dp. I reckon 48dp is a compromise between high efficiency (64dp) and high strength (32dp).

Anyway, with the modern re-released RC10's, AE switched the spur and pinion to 48dp but retained 32dp for internal gears in 6-gear trans. You will see this when your 40th car arrives.

Really appreciate the explanation, thanks! I've never changed the stock gearing in my limited RC past, and was more nitro than electric back then, we all left the stock gearing on those alone, and just adjusted the motor settings.

I'll get that 32dp on there when the asc6614 idler gears get here, and get everything back to stock.

Thanks again!

well put. Swapping six gear transmissions to 48 pitch pinion/spurs for off-road racing was also a thing back in the day.

Previous owner looked like he came from the on-road/carpet world... foam tires, 64 pitch gearing, locked diff, etc... maybe his local carpet track built some ramps to bring in more business.

For a Hasley build, definitely the 32 pitch pinion and white spur with a functioning diff. Breaking out a drill and going full Hasley is optional...

I'm looking forward to going very slowly and carefully around the yard when this one is finished .

[GreenBar0n]

Found someone 3D printing the asc6614 gears for $10, many people have bought them, and no complaints, quite the opposite it would seem.
https://www.ebay.com/itm/153727498232

[XLR8]

Found someone 3D printing the asc6614 gears for $10, many people have bought them, and no complaints, quite the opposite it would seem.
https://www.ebay.com/itm/153727498232

Hmmm, that's interesting and thank you for posting a link but I'd have to pass on them. There's a lot of gear reduction ahead of the idler gear so it is highly stressed and prone to failure even as a molded glass reinforced nylon part. I'm guessing your idler with a chipped tooth is stronger than any printed gear. If I got a set, they'd likely
be used only with a stock brushed motor, NiMH and for tooling around in the yard.

[GreenBar0n]

Found someone 3D printing the asc6614 gears for $10, many people have bought them, and no complaints, quite the opposite it would seem.
https://www.ebay.com/itm/153727498232

Hmmm, that's interesting and thank you for posting a link but I'd have to pass on them. There's a lot of gear reduction ahead of the idler gear so it is highly stressed and prone to failure even as a molded glass reinforced nylon part. I'm guessing your idler with a chipped tooth is stronger that any printed gear. If I got a set, they'd likely
be used only with a stock brushed motor, NiMH and for tooling around in the yard.

If you read or believe the comments on that seller, there was guy doing wheelies with brushless LiPo on those printed gears . Only NOS delrin idler gears for me though, but I was tempted to try them at half the price.

[XLR8]

Found someone 3D printing the asc6614 gears for $10, many people have bought them, and no complaints, quite the opposite it would seem.
https://www.ebay.com/itm/153727498232

Hmmm, that's interesting and thank you for posting a link but I'd have to pass on them. There's a lot of gear reduction ahead of the idler gear so it is highly stressed and prone to failure even as a molded glass reinforced nylon part. I'm guessing your idler with a chipped tooth is stronger that any printed gear. If I got a set, they'd likely
be used only with a stock brushed motor, NiMH and for tooling around in the yard.

If you read or believe the comments on that seller, there was guy doing wheelies with brushless LiPo on those printed gears . Only NOS delrin idler gears for me though, but I was tempted to try them at half the price.

I'm guessing that comment wasn't posted by Kevin Talbot.
Actually, doing wheelies really isn't harmful. It's the sudden shock to the drive train from the tires losing then suddenly gaining grip under throttle as the car lands from a jump or drives over rough terrain that really tests the integrity of gears. Remember, the 6-gear trans doesn't use a slipper clutch so the plastic idler gears become the sacrificial part in the drive train; the weak link in the chain.

[GreenBar0n]

I'm guessing that comment wasn't posted by Kevin Talbot.
Actually, doing wheelies really isn't harmful. It's the sudden shock to the drive train from the tires losing then suddenly gaining grip under throttle as the car lands from a jump or drives over rough terrain that really tests the integrity of gears. Remember, the 6-gear trans doesn't use a slipper clutch so the plastic idler gears become the sacrificial part in the drive train; the weak link in the chain.

That's why I think I have the chip on one idler gear. The guy who last ran this, put the softer silver springs on, and then put the collars near the bottom of the shocks, loading up the suspension so that it sits at the very top.


The angle was so steep that the axle stubs were biting the arms, look how bad one side got chomped.


Pretty sure that's the reason for the idler gear chip.

[XLR8]

I'm guessing that comment wasn't posted by Kevin Talbot.
Actually, doing wheelies really isn't harmful. It's the sudden shock to the drive train from the tires losing then suddenly gaining grip under throttle as the car lands from a jump or drives over rough terrain that really tests the integrity of gears. Remember, the 6-gear trans doesn't use a slipper clutch so the plastic idler gears become the sacrificial part in the drive train; the weak link in the chain.

That's why I think I have the chip on one idler gear. The guy who last ran this, put the softer silver springs on, and then put the collars near the bottom of the shocks, loading up the suspension so that it sits at the very top.


The angle was so steep that the axle stubs were biting the arms, look how bad one side got chomped.


Pretty sure that's the reason for the idler gear chip.

Ah, I've seen that before -- it eliminates all droop in the suspension which can be bad but probably not a big deal if the car ran on a dead flat surface. Over a rougher surface however, the tires would literally skip over the surface stressing the drive train and making the car really hard to drive. Droop is necessary to allow the tires to maintain contact with the surface.

It's also possible the tooth chipped because the nylon has become dry and brittle. Do you know about re-hydrating old nylon parts? Just clean them with warm water and dish soap to remove all traces of grease and oil, then rinse to remove the soap residue and drop the parts into a jar of water for a few days. This will allow the nylon to absorb water making the parts soft and pliable.