42131 Cat D11 Mods and improvements

[efferman]

The D11 is still a month away, but one change has to be done when it arrives. The upper sprocket has to be the driving gear.

.io

Edited August 30, 2021 by efferman

[jorgeopesi]

2 minutes ago, efferman said:

The D11 is still a month away, but one change has to be done when it arrives. The upper sprocket has to be the driving gear.

Just one?,  .

[efferman]

1 minute ago, jorgeopesi said:

Just one?,  .

There are more mods in my mind, but first i need this behemoth to see the available space.

[Andman]

For me it would be enough, if someone would mod the price into a more reasonable range :-D

@efferman, does driving the upper sprocket instead of the lower one at the back have any advantages? Or is just because of realism?

[Ngoc Nguyen]

Since there is no PF equivalent for the XL angular motor, how should I design the power source for the PF conversion version, I wonder 

[efferman]

4 minutes ago, Andman said:

Or is just because of realism?

Realism, and i want do the suspension of the real thing.

[Maaboo the Witch]

5 minutes ago, Ngoc Nguyen said:

Since there is no PF equivalent for the XL angular motor, how should I design the power source for the PF conversion version, I wonder 

The closest thing would be the XL motor. Adding some kind of superstructure with beams or the like to match the form factor would probably be your best shot.

[jorgeopesi]

8 minutes ago, efferman said:

Realism, and i want do the suspension of the real thing.

It would be nice to see but I think it is too much weight it will have to be a strong bar, Nico71 did it great in his tracked machines.

[Johnny1360]

10 hours ago, efferman said:

Realism, and i want do the suspension of the real thing.

That is cool start and I also had no idea that these beasts had any suspension at all, I always thought the best you could hope for was a spring under the seat, lol.

[Bartybum]

I’d be really interested if someone modded this to remove the PU and replace it with non-RC PF so that it can be controlled with levers.

[Bricktrain]

16 hours ago, efferman said:

The D11 is still a month away, but one change has to be done when it arrives. The upper sprocket has to be the driving gear.

That would also make it possible to remove the outer support for the upper sprocket, so it could be made to look more like the reduction hub there.

[JaBaCaDaBra]

17 hours ago, efferman said:

Realism, and i want do the suspension of the real thing.

Like "put the sprockets on the ground"

[Jundis]

2 minutes ago, JaBaCaDaBra said:

Like "put the sprockets on the ground"

My guess is, that this would hinder the turning of this thing in such a manner that Lego decided to make use of this trick. Ground pressure is a thing only relevant for real life machines, not Lego models (in the weight class < 10 kg).

[JaBaCaDaBra]

1 minute ago, Jundis said:

My guess is, that this would hinder the turning of this thing in such a manner that Lego decided to make use of this trick. Ground pressure is a thing only relevant for real life machines, not Lego models (in the weight class < 10 kg).

With these motors turning will be a piece of cake.
And the 8275 didn't have any problem too.
IE, it's just the next design fault.

[efferman]

4 hours ago, JaBaCaDaBra said:

Like "put the sprockets on the ground"

Done.

Needs still more reinforcements in the turntable area.

New file

[JaBaCaDaBra]

1 hour ago, efferman said:

Done.

MUCH better

[jorgeopesi]

2 hours ago, efferman said:

Done.

Needs still more reinforcements in the turntable area.

New file

What about using small turntables for the suspension bar, three would be a strong a very functional conjunt.

Edited August 31, 2021 by Milan
Do not quote images from the same page, please.

[efferman]

Good idea!

[Toitoine]

With the engine on top wheel, may be there is a risk that the tracks get out of the wheel under effort ?

but might be ok if the racks are straightened, any doubt.

Edited August 31, 2021 by Toitoine

[keymaker]

2 hours ago, Toitoine said:

With the engine on top wheel, may be there is a risk that the tracks get out of the wheel under effort

I wish to see some info from experts related to real machines, if we have anyone here. From my point of view, I would say that lower wheels are better to be powered, because there are more points of contact wheel with tracks.

Edited August 31, 2021 by keymaker

[brickless_kiwi]

 

http://info.texasfinaldrive.com/shop-talk-blog/caterpillar-high-drive-and-final-drives

Start reading...

What you have to understand and unless you have either operated one or worked on one is the size and weight.  Also ground clearance.  These are not little rinky dink machines where you can have a track drive in the boogey assembly. 

7 minutes ago, keymaker said:

I wish to see some info from experters related to real machines, if we have anyone here. From my point of view, I would say that lower wheels are better to be powered, because there are more points of contact wheel with 

[Milan]

20 minutes ago, keymaker said:

I wish to see some info from experters related to real machines, if we have anyone here. From my point of view, I would say that lower wheels are better to be powered, because there are more points of contact wheel with tracks.

- Impacts on the lower undercarriage are not transmitted to the powertrain located above
- drivetrain is well above all the dirt, dust, rocks, gravel etc...
- drivetrain does not have to hold the weght of the machine
- easier and more accessible maintenance
- more track can be on the surface, without having to extend the chassis to fit the motors in the back

[keymaker]

Wow, @brickless_kiwi, thank you for the link but your answer sounds like you somehow took my lack of knowledge personally :D

@Milan s answer is much more informative without "additions"

In matter of fact, I did MOC Tracked Dozer D10T a while ago and I was aware of most of pros mentioned by Milan, but I also noticed cons I mentioned earlier. It looks like that in this case, more pros than cons for upper drive system 

[efferman]

The actuators will be mounted more realistic too

[efferman]

The actuator mount seems to be solid, and holy moly, this thing will be huge.

Btw, the Fake motor and the Gearbox is history.