42129 - 4x4 Mercedes-Benz Zetros

[Timorzelorzworz]

12 hours ago, lmdesigner42 said:

There are various official pictures up for the Zetros on the US shop. There seems to be something unusual going on with the rear axle. I'm seeing two shafts going to the rear axle and several red and LBG 16-tooth gears. This makes me think there is one of two following possibilities instead of the normal differential position:

1. Rear diff is in chassis with two outputs going to the rear axle through separate shafts.
2. Rear diff and locker are in the rear axle, but mounted perpendicular.

If you look at pictures of the rear, there are several red and yellow axles in the rear axle rotated at different angles, this supports the idea that there is something more going on in there.

There are three of the new joints in this set. One is for the front axle to drive, the second one is for the rear axle to drive and the third one goes also to the rear axle to lock the differential. That is the reason that for that purpose there is no need for motor with encoded position, because the mechanism to lock the center and rear differential goes through many gears and shafts simultanously. This is just zero ore one - either the diffs are locked or not, a center position is not needed. In case the medium motor turns too long, the clutch will affect. Positioning of motor is just needed when the central position matters, like steering or gearbox with more than two ratios.

Edited July 8, 2021 by Timorzelorzworz

[2GodBDGlory]

I wonder if the code will be able to sense they increased current the motor would be drawing when slipping the clutch, and essentially self-synchronize each time it reaches an extreme position.

[gyenesvi]

19 hours ago, 2GodBDGlory said:

I wonder if the code will be able to sense they increased current the motor would be drawing when slipping the clutch, and essentially self-synchronize each time it reaches an extreme position.

I don't think such complexity is required. Instead, if it takes let's say 0.7 seconds of motor rotation to lock the diffs, then it's enough to program the motor to run for 1 second when you press the lock button. It will overshoot a bit, but the physical extreme positions and the clutch will take care of the synchronization.

[Timorzelorzworz]

2 hours ago, gyenesvi said:

I don't think such complexity is required. Instead, if it takes let's say 0.7 seconds of motor rotation to lock the diffs, then it's enough to program the motor to run for 1 second when you press the lock button. It will overshoot a bit, but the physical extreme positions and the clutch will take care of the synchronization.

Exactly, due the drivetrain with space in gears and joints, the exact angle of motor rotation is not 100% predictable to lock/unlock the diffs. To use a motor with a sepcified turning in seconds instead of exact angle rotation is the right choice in the model. The clutch will catch the overspeed.

[LegoBuilder919]

On 12/17/2020 at 5:19 AM, Bartybum said:

The rumoured price seems too high for a four wheel vehicle with a simple hub and two motors. Unless it has pneumatics. I’m really hoping it’s got RC pneumatics, however unlikely.

RC pneumatics would be so cool.

[Maaboo the Witch]

13 minutes ago, LegoBuilder919 said:

RC pneumatics would be so cool.

Well, they're not in this set.

[Bartybum]

7 hours ago, LegoBuilder919 said:

RC pneumatics would be so cool.

Nah not even RC.

6 hours ago, Maaboo35 said:

Well, they're not in this set.

Uh... well yes I think they know.

[Maaboo the Witch]

7 hours ago, Bartybum said:

Uh... well yes I think they know.

No! Really?

[Bartybum]

1 minute ago, Maaboo35 said:

No! Really?

?

Anyway... Checking B&P and it doesn't seem we can buy the new pieces yet. Ah well, just gotta wait

[Maaboo the Witch]

14 minutes ago, Bartybum said:

Checking B&P and it doesn't seem we can buy the new pieces yet.

The set hasn't been released yet, that's probably why.

[1gor]

2 hours ago, Maaboo35 said:

No! Really?

 

[2GodBDGlory]

11 hours ago, Bartybum said:

?

Anyway... Checking B&P and it doesn't seem we can buy the new pieces yet. Ah well, just gotta wait

They wouldn't let me download the instructions either!

The nerve!

[TeamThrifty]

Does the embargo lift today? 12th rings a bell but i could be wrong...

[1gor]

33 minutes ago, TeamThrifty said:

Does the embargo lift today? 12th rings a bell but i could be wrong...

I think at 16th...

[AVCampos]

Yes, 16th.

[2GodBDGlory]

Wow!

That's soon all of a sudden!

[Ngoc Nguyen]

 

The set that this guy received has the battery box with the pop open lid

[MP LEGO Technic creations]

27 minutes ago, Ngoc Nguyen said:

The set that this guy received has the battery box with the pop open lid

I also noticed that. I think that's better than four screws, though...

Edited July 14, 2021 by MP LEGO Technic creations

[Aleh]

I got the following truth: independently of how huge the price will be, blogers will continue to review the model, advertising it doing this, fans will buy it, and TLG will produce more expensive set with less functions, which blogers will review, obviously. Circle closes. Bur here, at home on the sofa they (we) will keep whining how this or that set is expensive.

[Maaboo the Witch]

Poor guy, after all that time building it he won't be able to play with it for half a month. Such hardships bring a tear to one's eye. 

Edited July 14, 2021 by Maaboo35

[HectorMB]

8 minutes ago, Aleh said:

I got the following truth: independently of how huge the price will be, blogers will continue to review the model, advertising it doing this, fans will buy it, and TLG will produce more expensive set with less functions, which blogers will review, obviously. Circle closes. Bur here, at home on the sofa they (we) will keep whining how this or that set is expensive.

Absolutely true. Indeed, I found many similaritites with the Apple/iPhones escalade. Few years ago, thinking about getting a phone more expensive than 300-400 was just unbelievable. Then, Apple start rising, year by year, the prices of the iPhones. A critical point was crossing the 100EUR barrier... but the people kept buying them. At least, in that case, the increase of price came with top tech specs. TLC, I think, is doing the same: in the last years we have seen a continuous increase of the prices; sometimes it was reasobnable (more parts, or more complex parts). But I think that now, they keep increasing the price to see how much they can do maintaining the profit. The rationale behind I think that is easier to produce fewer sets getting the same or even more benefit, but this is just a guess. 

Anyway, for me, besides the cool looking of the set, i will pass. And, of course, I will do it because of the price. The set is fine, but asking that amount of money, I think, is just crazy. 

[blondasek]

51 minutes ago, Maaboo35 said:

Poor guy, after all that time building it he won't be able to play with it for half a month. Such hardships bring a tear to one's eye. 

Why you do think that? He can always create his own profle in any app and drive it around :)

[Maaboo the Witch]

2 hours ago, blondasek said:

Why you do think that? He can always create his own profle in any app and drive it around :)

Will he actually do that, though?

[2GodBDGlory]

Does he mention whether there is a real gearbox or not? If there is one, I guess it would have to be linked to the differential lock.

[Zerobricks]

From all the photos I think the driveline is as following:

Both L motors directly drive (there is no gearbox) a red old styled 4L Diff via 24 tooth gears - That's 1:1 ratio

The power from the central diff is sent via CV joints to a 3 x 16 tooth gears - Still a 1:1 ratio

The power is than sent to a 28 tooth diff via 12 tooth gear ratio - That's a 2,33 ratio.

Finally the hubs gear down additional 5,4 times.

The final gear ratio is 12,6x.

Combined that with the stalled torque number of 26 Ncm from Philo's website and x2 motors, the final ideal torque should be 655,2 Ncm, which is a really high number, especially with these small wheels. For comparison my original Fox 8x8x8 generated around 1000 Ncm.

Wheel RPM should be 315 rpm / 12,6 which is 25 rpm.

25 rpm with the 81 mm sized wheels gives a top speed of around 100 mm/second or 0,4 km/h.

Edited July 15, 2021 by Zerobricks