[MOD] PF Conversions for C+ sets - Directory

[2GodBDGlory]

1 hour ago, Void_S said:

I think it may requre a steeper with a ratched assembly, a-la Big Porche shift padders, so the gearbox shifts when the servo rotate at 90 degrees and does nothing when the servo auto-returns. So each servo activation will mean the chage to a higer or lower gear. 

That would work very well, and would allow all three speeds and the bed to be operated, but I was assuming that that wouldn't fit (and would definitely be a major modification) so I was just suggesting to hook it directly up to the wave selector, and then using its three different 90 degree positions to control the bed and two of the speeds (with the third one being ignored)

[Ngoc Nguyen]

Got my paws on the the 42129 the other day and quickly incorporated the PF mod (Servo steer) into it. I'm very happy with how the set performs and the decision to go for the PF mod instead. It doesn't perform any worse than the standard design, and whenever I want to play with it I can just turn on the switch, pick up the IR controller, and start driving. No need to wait for all the hassles of app config, calibration, update, errors and whatnot.

[gyenesvi]

1 hour ago, Ngoc Nguyen said:

It doesn't perform any worse than the standard design

I wonder what environment you used for your comparison (though it's hard to do a really tough test with the Zetros on rough terrain). While I agree that in many cases the PF version could work just as well as the PU version, and even simpler to use with the physical remote, I'd say in case of a trial truck PU does have advantages; namely the position encoders allow for things that are not possible with PF:

- for steering, the PF servo cannot turn small angles with high torque (the torque decreases as the angle decreases as it is modulated by the voltage), but the PU L motor can turn low angles with high power. In fact, PF RC rock crawlers often don't use a servo because it's not strong enough for that application on real terrain, while in my experience the PU L motor is pretty good for steering even on rough terrain.

- for drive, the PF L motor cannot move slowly with high torque (similar reason, slow speed is achieved with low voltage), but the PU motors can move very slowly with full torque, and that's immensely useful for precision crawling, for example when climbing on a slippery slope, full throttle could make the wheels slip easier.

I wonder what other people's experience is about this topic, as I feel that these details are often overlooked about PU motors.

 

[Ngoc Nguyen]

1 hour ago, gyenesvi said:

I wonder what environment you used for your comparison

I'm just a casual fan who likes to take things out and make them go for a few rides and put them back on shelves. I'm not really into all the off-road or extreme trials. So even though PU system has its advantages as you said, they don't increase the values of this particular set to 42129 me and don't outweigh the hassles that running the C+ app involves.

 

Edited October 22, 2021 by Ngoc Nguyen

[2GodBDGlory]

Those are some interesting points about the torque difference at part power. In my experience the PF motors seem to perform better though, at least for fast cars. I think that PF has better response times and that the electronic protection is less restrictive, allowing for quicker acceleration. I haven't tried a PU crawler, though.

[Ngoc Nguyen]

5 hours ago, gyenesvi said:

- for steering, the PF servo cannot turn small angles with high torque (the torque decreases as the angle decreases as it is modulated by the voltage), but the PU L motor can turn low angles with high power. In fact, PF RC rock crawlers often don't use a servo because it's not strong enough for that application on real terrain, while in my experience the PU L motor is pretty good for steering even on rough terrain.

And funnily enough, the used Servo I bought was slightly broken. It can't return to center automatically, but that turns out to be a blessing, because thanks to that defect it's can be controlled proportionally. So it functions like a high torque L motor.

[gyenesvi]

8 hours ago, Ngoc Nguyen said:

I'm just a casual fan who likes to take things out and make them go for a few rides

Fair enough, which one is more advantageous does depend on the kind of usage.

4 hours ago, 2GodBDGlory said:

In my experience the PF motors seem to perform better though, at least for fast cars.

Sure, for fast cars the advantage may disappear.

3 hours ago, Ngoc Nguyen said:

It can't return to center automatically, but that turns out to be a blessing, because thanks to that defect it's can be controlled proportionally.

Do you mean with a non-proportional controller?

[Ngoc Nguyen]

3 hours ago, gyenesvi said:

Do you mean with a non-proportional controller

Yes. I can control it proportionally with normal PF controller.

[technicfan]

A couple of things?, was there any way that the 42114 could have the battery mounted behind the cab?. Does it go better with PF than Control + do you think?. Please tell me that you will do a PF conversion for the D11?. Thanks.

[Ngoc Nguyen]

1 hour ago, technicfan said:

was there any way that the 42114 could have the battery mounted behind the cab?

Yes. I did it here.

 

https://rebrickable.com/mocs/MOC-85933/nguyengiangoc/42114-pf-conversion-servo-motor-steer/

 

 

1 hour ago, technicfan said:

Does it go better with PF than Control + do you think?.

For me it is better with PF. I got rid of the sequential gearbox, so the 42114 PF only has 3 motorized functions: driving, steering, and dumping. And as mentioned, I'm just a casual fan who likes to take things out and make them go for a few rides and put them back on shelves, so the PF setup suits my need better.

 

1 hour ago, technicfan said:

Please tell me that you will do a PF conversion for the D11?. Thanks.

I'm working on it. I'm trying to squeeze 7 L motors, 4 IR receivers, and 2 battery boxes into the things without having to remove or redesign too much.

[Ngoc Nguyen]

My PF Conversion mod for 42131 is available on rebrickable: 

https://rebrickable.com/mocs/MOC-92919/nguyengiangoc/42131-pf-conversion/

 

This mod allows the set 42131 to be controlled by PF elements. The PF elements in this mod are:

- 2 Battery Boxes
- 4 IR receivers
- 7 L motors

This version has 7 functions:

- Right track control
- Left track control
- Blade pitch
- Blade tilt
- Ripper pitch
- Ripper tilt
- Ladder control

[Ngoc Nguyen]

On 10/6/2021 at 7:53 PM, Ngoc Nguyen said:

I learned the hard way that the L motor doesn't steer very well. It can steer while the front wheels are rolling, but can't steer when the model is standing still. The direct output from the motor doesn't have enough torque to overcome the weight and friction of the wheels.

Ever since this happened, I've been troubled by it. If the direct output from the L motor can't steer the 42124, then it can't steer the 42129. I have already posted a 42129 L-motor steering mod on Rebrickable, and I don't want to post something that doesn't work.

After some tinkering I've finally found a solution. I replaced the L motor with the M motor to save space, and let the output goes through a 12-20 gear mesh and a linear clutch. It should have enough power to steer the model then. If it turns out to be not enough, the gearing can be replaced with a 8-24 one. 

I've changed the L-motor steer mod on Rebrickable into the M-motor steer mod and updated other stuff accordingly.

https://rebrickable.com/mocs/MOC-84984/nguyengiangoc/42129-pf-conversion-m-motor-steer/#details

[Ngoc Nguyen]

Got my paws on the 42131 and put the PF mod on it. I must say I'm very happy with the result. It works like a charm. Two PF L motors are enough to drive this thing around at reasonable speeds. The immediacy of PF allows me to pick up the IR controller and play with it after simply turning on two battery boxes. Channel 1 for drive, 2 for blade, 3 for ripper, and 4 for ladder. No app, no update, no config whatsoever.

It's a shame that I have to do the PF mod myself instead of being able to buy the PF version as an official set.

[Ngoc Nguyen]

42160 PF Mod is complete.

 

Instruction is coming after the official instruction is available.

[Ngoc Nguyen]

It's time I finished the PF conversion V2 for 42114.

The motor arrangement for V1 is this. 

 

XL motor attached to fake engine and front axle for drive, Servo motor for steer, and L motor for tipping bed. Orange for drive, red for steer, blue for tipping.

There are a couple of issues with this design:

- It is not accurate. Someone pointed out that the motor should go to the middle differential instead. I'm not sure if the setup in the real AH60 is like that, but the design in other RC Technic models is also like that (42070 A, 42070 B, 42129).

- The servo motor doesn't allow precise steering. 

- The steering wheel isn't working because it's not connected to the steering column.

 

The new motor setup is like this.

 

Still orange for drive, red for steer, blue for tipping. This time I used a horizontal L motor for steer. It will connect directly to the steering wheel on the top and go through a series of gear reduction on the bottom.

The L motor formerly used to tip the bed now drives the wheels (the orange one).. It is connected to the 8z gear and that connects to the middle differential. If that setup turns out to be too slow I can connect the motor to the other end of the differential instead.

The gear that tips the bed is now put behind the frame.

[1gor]

If it helps; motor output is to central differential...

...or better to say to transmission (it is between front axle and central differential)...

Edited August 26, 2023 by 1gor

[Maaboo the Witch]

5 minutes ago, 1gor said:

If it helps; motor output is to central differential...

...or better to say to transmission (it is between front axle and central differential)...

That's an A40D, not an A60H! *slaps your knuckles with a yardstick*

[Ngoc Nguyen]

11 minutes ago, 1gor said:

motor output is to central differential...

Where is central differential in that photo? Can you circle it

[1gor]

2 hours ago, Ngoc Nguyen said:

Where is central differential in that photo? Can you circle it

At first I thought (based on brochure) that it is just behind transmission, but looking other images it seems like it is inside transmission housung...

@Maaboo35, on sunset I can go and search for (a kind of) stick, but brochures (on which I'am automatically redirecting due place where I am) cover larger articulated haulers (35, 40, 50, 60) and as image representation of drivetrain it is used on model 40. Of course if Your Highness has this kind of image with AH60 showing drivetrain, I think @Ngoc Nguyen would find it usefull 

[Ngoc Nguyen]

Gotta dress things up a lil bit.

[Ngoc Nguyen]

And it's on:

https://rebrickable.com/mocs/MOC-161275/nguyengiangoc/42160-pf-conversion/#details

[Ngoc Nguyen]

Check the first post to see the graphical updates!

[Zerobricks]

10 hours ago, Ngoc Nguyen said:

And it's on:

https://rebrickable.com/mocs/MOC-161275/nguyengiangoc/42160-pf-conversion/#details

Well done, good idea using L motors and clutch gears instead of hard-to-find servo motor for steering. How would you rate performance compared to the PU one?

[Ngoc Nguyen]

7 minutes ago, Zerobricks said:

Well done, good idea using L motors and clutch gears instead of hard-to-find servo motor for steering. How would you rate performance compared to the PU one?

Indeed, for most of the PF conversion mods I include a non-servo option to reduce the dependence on that thing. The only case in which a Servo performs better is the 42124, simply due to a constraint in space. 

As for the comparison, I can't tell since I haven't got my paws on my 42160 yet. And since I asked my vendor to remove the Power Up components from the set I can't compare after I get the set either. I have no use for spare smart hubs and PU motors.

[Ngoc Nguyen]

Finally got time to redesign the 42114 PF version so that the functions properly.

 

 

In this version the driving motor is connected to the middle differential, and the steering motor also drives the steering wheel, just like in the original model.