[Jnbrown3]

Hi there, does anyone know this transfer coupler hub? Love the design, concerned about the shear strength of those bolts transferring the energy to this little bolts in shear on the clutch piece. If this is as Good design I am super excited because the strap any clutch piece directly to it. Also, I suppose we weld as well. Any thought???

 

[kennybobby]

i would be concerned that the aluminum hub would pull out and fail before the steel bolt would shear. Not a good material in a drivetrain or gearbox.

 

[DaveEV]

Not familiar, but could see it possibly absorbing shock and misalignment. Can you unbolt and show us what is below what remains of the clutch?

 

[remy_martian]

You don't say what the bolt sizes and materials are or the radius of them from the hub center. No clue of what the hub looks like on the back side - keyed?

So, impossible to say other than an eyeball guess without at least that info.

It looks really nice, clearly done by a metal craftsman, but it has a lot of really dumb engineering choices in it from just looking at it. But, it may be fine if it's attached to a low torque/power motor.

Not enough info.

 

[Bratitude]

i have a write up on making a coupler, its for the leaf motor, but its a tried and true method.

https://bratindustries.net/how-to-mate-a-nissan-leaf-electric-motor-to-a-manual-transmission-the-motor-coupler/

 

[kstegath]

1. That's the center section of a clutch disc.
2. The transmission input shaft is not directly connected to the engine's flywheel or the clutch pressure plate.
3. The springs absorb engine pulses, and with an IC engine, it allows a smoother start.
4. When the drivetrain is "floating" (not accelerating or coasting), the minor vibrations are absorbed by the springs. Clutch disc parts

With quality bolts (grade 8), when the bolts are tight, it will take huge torque to shear those connections.

 

[remy_martian]

You were doing so well until that last paragraph.

The bolt circle here is a half to a third that of a pressure plate and the bolt count is about a third.

If you want to compare the torque handling of this as compared to its original friction disk and pressure plate...not even close.

 

[kstegath]

You were doing so well until that last paragraph.

The bolt circle here is a half to a third that of a pressure plate and the bolt count is about a third.

If you want to compare the torque handling of this as compared to its original friction disk and pressure plate...not even close.

Hi Remy,

I understand what you're saying and I'm still questioning my reasoning!

But when the clutch is depressed:​

1. The disc, hub, and transmission input shaft are floating
2. As the clutch is being released, the only rigid connection between the friction material and the hub/transmission input shaft are those bolts. 

• I've looked at racing clutches, multi-disc clutches, and wet motorcycle clutches.
• I'm still looking for a mistake in my reasoning.
• I agree that when the clutch is released the flywheel, pressure plate, and a non-spring friction disc act as a rigid unit. But even then, isn't the ultimate shear point those bolts/rivets?
  • Which is why I said it would take huge torque to shear those bolts.

Thoughts on this?

 

[remy_martian]

Valid point.

The bushings around the bolts also resist some of that shear load (would be different with loose bolts, in other words), but I now see your point and agree - if you substract the shear reduction contribution of those bolt bushings..

 

[Bratitude]

all i have to say on the matter is: do electric oem and race gearboxes use clutches, pressure plates, or dampening springs?

no

 

[remy_martian]

Some do...

But definitely not like this 😂