6s Diff differences...??

[BashingBrian]

Can anyone explain to me the difference between the Typhon and Kraton diffs, I know one is straight cut and one is spiral but what does this actually mean..??

Why do some cars come with the spiral and others straight and what are the pro's and con's of each one..???

 

[bicketybam]

Can anyone explain to me the difference between the Typhon and Kraton diffs, I know one is straight cut and one is spiral but what does this actually mean..??

Why do some cars come with the spiral and others straight and what are the pro's and con's of each one..???

The diff pinion tooth count is different between that two to compensate for the much smaller tires on the Typhon (13t for Typhon, 10t for the Kraton). They basically "geared up the diffs" a bit more on the Typhon. As to why one is straight cut and one is spiral, I couldn't tell you. But it prevents you from throwing the Typhon diff pinion in your Kraton to gear it up.

 

[slick2500]

Spiral cut gears are "stronger" than straight cut because you get more gear contact than you do with straight cut gears.

 

[bicketybam]

Spiral cut gears are "stronger" than straight cut because you get more gear contact than you do with straight cut gears.

Huh. There's a guy on this forum with decades of experience who thinks the spiral cut gears on the Kraton 8S might be an issue ?

 

[joostin420]

 

[crimsonfancy]

Solid info and could even be considered entertaining (be ready for almost 2 min of jaw flappin before the real info comes.) Makes sense and easy to understand. Inspired me to browse the rest of the channel.

 

[Ari33]

Helical gears obviously have a larger gear tooth contact patch and so the teeth are a bit stronger in themselves.. also a lot quieter too. They do produce axial (sideways) loads though which generates more friction and heat. Heavier Strengthed gearbox cases usually have to designed to cater for the axial loads.

Straight cut gears are widely used in motorsport where gear whine is a non issue. Far simpler and easier to work with. They are typically considered to be a bit more efficient allowing more torque to be transferred directly to the other cog rather than it being divided by the created axial (sideways) force. The gearbox case can also typically be built lighter due to not having axial loads to contend with.


Edit- Beaten to it by the above video... which earned my sub for being well produced with good content.

 

[slick2500]

Huh. There's a guy on this forum with decades of experience who thinks the spiral cut gears on the Kraton 8S might be an issue ?

Huh?

 

[SrC]

Bevel is better for heavy loading. The 8S has an extreme angle true bevel unlike the Kraton 6S which for some is even hard to see visually that it's slightly beveled. Bevel gears can handle a tighter mesh with less wear versus straight cut gears. Beveled has more contact area depending on how much gear angle is designed into it. Beveled gearing is much more costly to machine. Beveled gearing is a GOOD thing.
The Typhon's front and rear diff ring/pin. ratios (43/13) are taller because the tires are a smaller buggy size diameter. They tried to maintain the roll out and Final drive ratio to match the larger wheeled 6S BLX ESC and motor .

 

[MrTitanium]

Straight cute gears are stronger, yet noisier, than spiral cut units. Shimming spiral cut gears are more difficult to shim due to their helical design.

 

[SrC]

Shimming Helical/spiral/bevel cut gears is no more harder to shim than Straight cut. IMO Correct Backlash is your friend. Patience is a virtue.
Straight cut gears are not necessarily stronger. The type and grade of metals used determines that. Also, a cast versus a Billet cnc'ed machining plays into that. Casted gears will shatter much more easily. Spiral (bevel) gears work best with a tighter mesh. Straight cut are more efficient meshed looser. And generally noisier(gear chatter) due to less surface area contact than a Spiral G.mesh. Spiral gears don't like to be run in a fast and reversed rotation under load. That will contribute to failure with chipped teeth resulting. I refer to my Axial Crawler F/R diffs. as one example.
All the above assumes that both types of gears are shimmed with the proper amount of backlash.

 

[BashingBrian]

Spiral gears don't like to be run in a fast and reversed rotation under load. That will contribute to failure with chipped teeth

That's interesting to know..???

 

[Jimbobjr]

If straight cut gears were stronger all gears would be straight. Helical gearing is far and away harder to machine and requires more engineering. Making a gear tooth curved on a helix angle gives you more tooth without making the gear any wider. These angles do produce more stress on a gear box housing though so where there is room for wider gears or stronger materials can be used straight gears are the best way to go. In tight quarters like an rc bulk head a helical gear will be stronger every time provided the bulkhead does not flex and change the center distances under load.

 

[slick2500]

If straight cut gears were stronger all gears would be straight. Helical gearing is far and away harder to machine and requires more engineering. Making a gear tooth curved on a helix angle gives you more tooth without making the gear any wider. These angles do produce more stress on a gear box housing though so where there is room for wider gears or stronger materials can be used straight gears are the best way to go. In tight quarters like an rc bulk head a helical gear will be stronger every time provided the bulkhead does not flex and change the center distances under load.

And this right here is what I believe is one of the causes of guys constantly losing diffs in their rigs. The bulkheads in these are plastic and they flex a lot, and that flex is what causes the ring and pinion to chip teeth.

 

[Jimbobjr]

And this right here is what I believe is one of the causes of guys constantly losing diffs in their rigs. The bulkheads in these are plastic and they flex a lot, and that flex is what causes the ring and pinion to chip teeth.

Once I learned to drive my diff issues went away with these rigs.

 

[bicketybam]

Once I learned to drive my diff issues went away with these rigs.

Thank you for saying that. Same for me.

 

[slick2500]

Once I learned to drive my diff issues went away with these rigs.

Like I said 1 of the causes. I was more talking about guys like @Notorious J and @olds97_lss. Under stress the bulkhead halves can actually separate, I've seen guys who had the screws holding the halves together back out.

All of my "issues" came from something else failing.
1st set the bearings let go on the pinion.
2nd set the motor locked up mid backflip.
1 front diff because the diff cup slid back on the pinion shaft

 

[Jerry-rigged]

Once I learned to drive my diff issues went away with these rigs.

Exactly. 3 years with my pair of V1's, and very little diff issues. The biggest issue I have is with the case-side bearing failing, seizing, and breaking the case - which leads to chipped teeth. But still, that has only been twice.

 

[jym73]

Straight cute gears are stronger, yet noisier, than spiral cut units.

That's why helical gears are used for more heavy load than straight gears

 

[MrTitanium]

I stand corrected: straight cut gears are not stronger than helical gears.

There’s no need to roll your eyes jym73, as I’m sure you’ve made mistakes.