Kraton Difference between Castle Torque and Punch Control Settings?

[nyev]

Based on prior threads, my understanding is that with Castle ESC's, Torque Control limits the actual torque a motor is able to deliver. With torque being defined as, the amount of rotational force the motor can deliver. From what I understand, Punch Control imposes a limitation on how fast the motor actually responds to an increase in the input throttle signal from the receiver.

First, is what I said above correct? And if so, my real question is, under what scenarios would one choose to limit torque versus limiting punch?

The main reason I am interested in toying with these is that on my Kraton EXB, after 10 packs or all three of my diff output drive cups "behind" the center diff, including the center diff output cup that faces rear plus the two out-drive cups on the rear diff, started to get chewed up by the dogbones.

I was running 500k center diff fluid which probably has something to do with it. With thicker fluid more engine force gets applied to the wheels that get traction under acceleration, which are the rear wheels. I was also using the 25% punch control setting and no torque control.

Since then I've replaced the 500k center diff fluid with 200k fluid, replaced the EXB output drive cups with M2C output drive cups (which really look exactly the same in terms of dimensions and thickness of the material), and bumped up punch control to 30%. I'm now wondering if I should introduce a bit of torque control as well....

 

[Nautilus802]

I would probably look into dropping to 4s or 5s, or using a bigger pinion to limit the effect of the torque, or both, before I intentionally gimped the motor’s output.

(ok after thinking about this a little more, dropping to 4s or 5s may be a suboptimal solution, especially if torque control allows you to eventually reach the same top speed at a given voltage, at the cost of acceleration. A bigger pinion would give you higher top speed, but if you have no interest in that, using torque control might indeed be the best way to go assuming reducing the torque output didn’t raise motor temps.)

 

[Twitchfast]

Based on prior threads, my understanding is that with Castle ESC's, Torque Control limits the actual torque a motor is able to deliver. With torque being defined as, the amount of rotational force the motor can deliver. From what I understand, Punch Control imposes a limitation on how fast the motor actually responds to an increase in the input throttle signal from the receiver.

First, is what I said above correct? And if so, my real question is, under what scenarios would one choose to limit torque versus limiting punch?

The main reason I am interested in toying with these is that on my Kraton EXB, after 10 packs or all three of my diff output drive cups "behind" the center diff, including the center diff output cup that faces rear plus the two out-drive cups on the rear diff, started to get chewed up by the dogbones.

I was running 500k center diff fluid which probably has something to do with it. With thicker fluid more engine force gets applied to the wheels that get traction under acceleration, which are the rear wheels. I was also using the 25% punch control setting and no torque control.

Since then I've replaced the 500k center diff fluid with 200k fluid, replaced the EXB output drive cups with M2C output drive cups (which really look exactly the same in terms of dimensions and thickness of the material), and bumped up punch control to 30%. I'm now wondering if I should introduce a bit of torque control as well....

Punch control merely limits the amount of "punch" the system is allowed to output from a dead stop/near dead stop iirc.
Castle's Torque limiter is a variable reduction in torque, I use it on my Futaba T4PM because it has a dial I can use to adjust my torque on the fly.

So realistically you should only lower punch if you feel it's too violent at start-up, and torque limit if you're hitting issues while driving around.
I added the torque limiter because I'm running relatively big electronics in a stretched Typhon and it consistently breaks free from the ground due to the torque.

 

[nyev]

I would probably look into dropping to 4s or 5s, or using a bigger pinion to limit torque, or both, before I intentionally gimped the motor’s output.

Yes, I was debating whether or not to touch torque at all. I might see how things go with the other measures I've put in place (increasing punch control to 30% from 25%, changing center diff fluid from 500k to 200k, and swapping out the EXB out-drive cups for M2C cups).

Punch control merely limits the amount of "punch" the system is allowed to output from a dead stop/near dead stop iirc.
Castle's Torque limiter is a variable reduction in torque, I use it on my Futaba T4PM because it has a dial I can use to adjust my torque on the fly.

So realistically you should only lower punch if you feel it's too violent at start-up, and torque limit if you're hitting issues while driving around.
I added the torque limiter because I'm running relatively big electronics in a stretched Typhon and it consistently breaks free from the ground due to the torque.

I'm running a 7PXR and could also dial the torque setting dynamically if I wanted to. But I don't think I am running into any issues after I'm already running. I do have a fairly heavy rig, upgraded with M2C chassis, shock towers, etc.

From your explanation it sounds like I need to look at limiting punch control from a dead stop, as presumably the sudden force at startup is where the out-drive cups take the most abuse.

 

[Nautilus802]

Yes, I was debating whether or not to touch torque at all. I might see how things go with the other measures I've put in place (increasing punch control to 30% from 25%, changing center diff fluid from 500k to 200k, and swapping out the EXB out-drive cups for M2C cups).




I'm running a 7PXR and could also dial the torque setting dynamically if I wanted to. But I don't think I am running into any issues after I'm already running. I do have a fairly heavy rig, upgraded with M2C chassis, shock towers, etc.

From your explanation it sounds like I need to look at limiting punch control from a dead stop, as presumably the sudden force at startup is where the out-drive cups take the most abus

Punch control merely limits the amount of "punch" the system is allowed to output from a dead stop/near dead stop iirc.
Castle's Torque limiter is a variable reduction in torque, I use it on my Futaba T4PM because it has a dial I can use to adjust my torque on the fly.

So realistically you should only lower punch if you feel it's too violent at start-up, and torque limit if you're hitting issues while driving around.
I added the torque limiter because I'm running relatively big electronics in a stretched Typhon and it consistently breaks free from the ground due to the torque.

See m

Yes, I was debating whether or not to touch torque at all. I might see how things go with the other measures I've put in place (increasing punch control to 30% from 25%, changing center diff fluid from 500k to 200k, and swapping out the EXB out-drive cups for M2C cups).




I'm running a 7PXR and could also dial the torque setting dynamically if I wanted to. But I don't think I am running into any issues after I'm already running. I do have a fairly heavy rig, upgraded with M2C chassis, shock towers, etc.

From your explanation it sounds like I need to look at limiting punch control from a dead stop, as presumably the sudden force at startup is where the out-drive cups take the most abuse.

see my revised answer above. It could be that torque control could be your best option assuming you still have the same top speed at a given voltage and it doesn’t raise motor temps.

 

[nyev]

See m

see my revised answer above. It could be that torque control could be your best option assuming you still have the same top speed at a given voltage and it doesn’t raise motor temps.

Thanks. Maybe I'll simply add a touch of torque control, in conjunction with the added punch control. That way, there will be less sudden abuse on my diff output cups at startup from a dead stop, and also, less abuse from sudden increases in throttle while already running...

 

[Twitchfast]

Yes, I was debating whether or not to touch torque at all. I might see how things go with the other measures I've put in place (increasing punch control to 30% from 25%, changing center diff fluid from 500k to 200k, and swapping out the EXB out-drive cups for M2C cups).




I'm running a 7PXR and could also dial the torque setting dynamically if I wanted to. But I don't think I am running into any issues after I'm already running. I do have a fairly heavy rig, upgraded with M2C chassis, shock towers, etc.

From your explanation it sounds like I need to look at limiting punch control from a dead stop, as presumably the sudden force at startup is where the out-drive cups take the most abuse.

I would assume that the sudden force at startup would be the main cause of cup damage, Castle's torque limiter is quite funky but helpful for me at very least.
I also believe the torque limiter affects top speed, simply because you've lost the torque required to overcome air resistance etc.

 

[nyev]

I guess another option is to disable punch control AND torque control in the Castle ESC, and instead introduce a brief delay to the transmitter trigger setpoints on my Futaba 7PXR, which this transmitter allows. I actually use this for when my son is running my truck (I also limit the max throttle for him too, which he doesn't like....).

Would introducing the throttle ramp up delay on the transmitter be better, worse, or the same as setting punch control on the ESC? One advantage I can think of is that ALL sudden changes in throttle would have this slight ramp-up delay, and not just when starting from a dead stop.

 

[Twitchfast]

I guess another option is to disable punch control AND torque control in the Castle ESC, and instead introduce a brief delay to the transmitter trigger setpoints on my Futaba 7PXR, which this transmitter allows. I actually use this for when my son is running my truck (I also limit the max throttle for him too, which he doesn't like....).

Would introducing the throttle ramp up delay on the transmitter be better, worse, or the same as setting punch control on the ESC? One advantage I can think of is that ALL sudden changes in throttle would have this slight ramp-up delay, and not just when starting from a dead stop.

I would assume that's a good thing? In hindsight I'd imagine the torque limiter was implemented to stop people burning out motors, since brushless motor controllers just force a ton of current till either the rotor moves or the windings burn.
Going explicitly by the name, I would assume the throttle ramp up delay would function as punch control across the entire throttle curve, so that could only be a good thing if you're trying to avoid drive train abuse.
To answer your question, I would expect that to be better than punch/torque limiting, though naturally each feature has their own pros/cons.

 

[@9G]

I've got a 7PXR too and was having an issue with keeping the car on the ground from startup especially if I hit the throttle hard. Went to Throttle Curve and changed to EXP and set up a curve in throttle that starts at around 25 to 30. Then I set the Punch Control on the ESC (MMX8S) to about the same percent (25 to 35). Also did the motor test so I could use the Torque Limiter and set that to 6 (the LOWER the number the more torque limiting you get). Then car (Talion) took off lovely after that. When I hit the throttle hard from a dead stop it would take off but the power wouldn't kick all the way in immediately like before which was causing me to flip, wheelie or spin out. Once I pressed down past that 25 to 30 percent then I'd get a another jolt of power which was good cause I was already moving from hitting hard at the dead stop...almost like a slight turbo kicking in.

 

[nyev]

I've got a 7PXR too and was having an issue with keeping the car on the ground from startup especially if I hit the throttle hard. Went to Throttle Curve and changed to EXP and set up a curve in throttle that starts at around 25 to 30. Then I set the Punch Control on the ESC (MMX8S) to about the same percent (25 to 35). Also did the motor test so I could use the Torque Limiter and set that to 6 (the LOWER the number the more torque limiting you get). Then car (Talion) took off lovely after that. When I hit the throttle hard from a dead stop it would take off but the power wouldn't kick all the way in immediately like before which was causing me to flip, wheelie or spin out. Once I pressed down past that 25 to 30 percent then I'd get a another jolt of power which was good cause I was already moving from hitting hard at the dead stop...almost like a slight turbo kicking in.

Ramp-up Delay Time is really my descriptive name for what the Futaba setting I'm referring to does. Typical of Futaba, the settings are not intuitively named. The setting in question is "Speed", and you can select "Throttle" or "Steering", which so far seems intuitive. Once you select "Throttle", you can reduce the "Turn" setting which defaults to 100, which effectively introduces ramp-up delay. You can also adjust the "Return" setting which impacts the ramp-down time, but I don't need to adjust this. If you change this setting, whenever you change the throttle input, you can see the TX throttle signal take a bit of time to "catch up" to your throttle setpoint, if you set the "Turn" setting down low enough to actually notice the delay... Which seems to me the same thing punch control on my MMX8s ESC does, but applied anywhere across the throttle band instead of only from a dead stop.

I think I'll try setting punch control to 30%, AND introduce a very slight ramp-up delay from my transmitter - maybe just tuning down to 90 instead of 100. And leave the torque control disabled.

UPDATE: I just realized the "Ramp-Up" setting on my transmitter allows you to designate two different points in the throttle curve with two different settings of ramp up delay. For example I could set a bigger delay in the first 30% of the throttle curve, and a smaller delay in the remaining throttle curve. This might be advantageous to getting enough wheelspin for jumping/flipping, while still protecting my drivetrain a bit.