42100 Liebherr R9800 Excavator

[doug72]

10 minutes ago, HRU_Bricks said:

It would not be too difficult to modify it for PF and remove the Control Plus parts for other builds (my intention). 

My thoughts as well, it wil be an interesting build. See other thread.

I note there are now three seperate threads on this topic.

[Enantiomeer]

10 minutes ago, HRU_Bricks said:

To get back onto why we all here...

The build so far is really good. It has the "Technic" feel which is a little surprising because it is a programmable set with position controlled motors that often negates the need for gearing and more complicate construction methods.

The use of position controlled motors does indeed enable speed control and reduces the need for gearing down. There is however a small catch and that is the fact that speed control becomes less accurate/smooth at very low speeds. For this model TLG chose to make the movement of the tracks quite slow. It is geared down 2 * 2 * 2 * 3 * 36/28 = 30.9 times. If you'd try to recreate that same slow speed range by controlling the motor you'd have to run in in the range of 0 to 3.2 % of the normal maximum speed. This would surely result in a not so smooth movement, actually eliminating one of the advantages of the controlled motors over the old PF system.

25 minutes ago, HRU_Bricks said:

There are a few pin choices that are interesting with axle pins being used as locator pins when standard black friction pins would give better stability in the frame.

I noticed the same, though in the end when everything is assembled this really isn't an issue. The model is quite sold.

 

One thing I noticed near the end of the build was that the fake hydraulics tubing just end in mid-air i.s.o. connecting to the linear actuators. The simplest solution I could think of was to take two 3L bars, two 2*1 technic beams and a technic bush and make this connector:

Next I connected this to the top end of one of the linear actuators like this:

Alternatively you could connect the tubing to the bottom side of the actuator by using a 4L bar and pushing that through the actuator holder, which would result in something like this:

I think these methods give a more convincing impression for the fake hydraulic tubing than the original instructions.

One thing I'm not sure about is the number of tubes required. Would each actuator in a real machine use one or two tubes? I would expect two tubes per actuator (one for oil supply and one for oil return) since it would enable simpler valve, motor and control systems. Does anybody know this for sure?

[Dylan M]

3 hours ago, Jim said:

We are not talking about ourselves, but about consumers who purchase a 400+ euro set which cannot be controlled like advertised.

But only for a while...(4+ days) 

[coinoperator]

5 hours ago, HRU_Bricks said:

Lastly,  just don't buy the set until the 1st of October 

Or you will be punished with a sticker on the box.

1 hour ago, Enantiomeer said:

more convincing impression

LOVE this...

[zoo]

1 hour ago, Enantiomeer said:

There is however a small catch and that is the fact that speed control becomes less accurate/smooth at very low speeds. For this model TLG chose to make the movement of the tracks quite slow. It is geared down 2 * 2 * 2 * 3 * 36/28 = 30.9 times. If you'd try to recreate that same slow speed range by controlling the motor you'd have to run in in the range of 0 to 3.2 % of the normal maximum speed. This would surely result in a not so smooth movement, actually eliminating one of the advantages of the controlled motors over the old PF system.

1/30.9 times the speed, 30.9 times the torque.

[suffocation]

1 hour ago, Enantiomeer said:

The use of position controlled motors does indeed enable speed control and reduces the need for gearing down. There is however a small catch and that is the fact that speed control becomes less accurate/smooth at very low speeds. For this model TLG chose to make the movement of the tracks quite slow. It is geared down 2 * 2 * 2 * 3 * 36/28 = 30.9 times. If you'd try to recreate that same slow speed range by controlling the motor you'd have to run in in the range of 0 to 3.2 % of the normal maximum speed. This would surely result in a not so smooth movement, actually eliminating one of the advantages of the controlled motors over the old PF system.

Where on earth did you get 30.9? The reduction is 17.87:1. And you're not accounting for torque increase.

[RussianGuy]

41 minutes ago, suffocation said:

Where on earth did you get 30.9? The reduction is 17.87:1. And you're not accounting for torque increase.

I don't want to be exceedingly nitpicky, but 125/7 is closer to 17.857 :)

[suffocation]

Just now, RussianGuy said:

I don't want to be exceedingly nitpicky, but 125/7 is closer to 17.857 :)

Drat

[Enantiomeer]

32 minutes ago, suffocation said:

Where on earth did you get 30.9?

By making a mistake.   Somehow I had it in my mind that this gear has 24 teeth, while in actuality it has 20.

35 minutes ago, suffocation said:

And you're not accounting for torque increase.

The torque increase does not affect speed control accuracy/smoothness. Hence I don't have to take it into account for this purpose.

For other purposes you of course do need to take the torque increase into account. For example when you choose in which step of the gearing down sequence you want/need to place the clutch.

[efferman]

2 hours ago, Enantiomeer said:

Would each actuator in a real machine use one or two tubes?

Two Tubes are the Lowest amount of neccessary Connections at doubleworking Cylinders.

[suffocation]

Just now, Enantiomeer said:

For other purposes you of course do need to take the torque increase into account. For example when you choose in which step of the gearing down sequence you want/need to place the clutch.

Excellent point! By the way, has any of the lucky early owners had the chance to make a tentative measurement of the slippage torque of the new linear clutches? I believe the white 24-tooth gears have a nominal 2.5 N/cm slippage threshold (not sure about that number).

[aminnich]

I have not been on here in quite some time, life has been busy. 

Although, I have been watching this set.  It looks good but the biggest thing that turns me away from it is the new Power-up system instead of the Power Functions.  I have a collection of PF stuff and to now have to buy something new and not compatible with the old is not cool in my opinion.  

Do we know a price?  B-model?  

From discussion, what do you guys think is the biggest "con" of this set? 

EDIT: $450?!?!?!?!  I thought 42030 was expensive when it first came out, but $250 seems cheap now 

 

Edited September 27, 2019 by aminnich

[suffocation]

1 minute ago, aminnich said:

From discussion, what do you guys think is the biggest "con" of this set?

No new building techniques.

[pleegwat]

35 minutes ago, efferman said:

Two Tubes are the Lowest amount of neccessary Connections at doubleworking Cylinders.

The cylinders work in pairs, and the pairs couild share tubes which would move the minimum down to 2 tubes per pair. Lego models with paired pneumatic cylinders typically do this in some fashion, but I expect any real machine would control them individually for improved stability control.

Some GIS gives me the impression the actual machine uses four hoses per cylinder - two at the base, and two in the middle (where the narrow and wide part slide between each other). On some cylinders, the hose to the midpoint of the cylinder runs along the cylinder itself, so all four connect to the base of the cylinder first.

[efferman]

Four hoses per cylinder? Never seen this at cranes, excavators or hydraulic machinery,  and iam working on things like this.

 

[Erik Leppen]

1 hour ago, aminnich said:

From discussion, what do you guys think is the biggest "con" of this set? 

I noted on this in the other topic (the one about Sariels video) but I'd say, it is the lack of a physical controller. Using a smartphone means no tactile feedback, and this means you have to look at the controller all the time, instaed of focusing on the model. Given that, what more is it, then, compared to just playing a smartphone game with a digital excavator? (This is exaggerated, but you get the point.)

In any case, it means you will have to switch your focus all the time between the controller and the model, which I expect to be very tiring.

If you could connect a game controller to it, things will get tons more interesting. Especially if there would be a way to program the controller input. (I don't know if there are peeps from third party electronics who are doing just that?)

The other big con, for me is: despite the huge novelty in electronic aspect, there's nothing new in mechanical aspect. Same problem as 8275, but 3x as expensive.

[Enantiomeer]

1 hour ago, suffocation said:

By the way, has any of the lucky early owners had the chance to make a tentative measurement of the slippage torque of the new linear clutches? I believe the white 24-tooth gears have a nominal 2.5 N/cm slippage threshold (not sure about that number).

The torque value of the (different versions of) 24 tooth clutch gear is discussed here.

I do have all three versions of the 24 tooth clutch gear. I just tried to check if I could feel any difference between those and found that they are highly inconsistent (not really a surprise). When rotating the gear over one complete revolution I could clearly feel that at certain points in the rotation the required torque was much higher and then after passing those points the torque suddenly dropped dramatically.

This behavior will make it more difficult to obtain reliable measurements for the torque threshold (without using specialized equipment which is quite expensive).

Based on how the new linear clutch is designed I expect a similar behavior.

I'll check if the machine workshop at my company has any suitable low range torque measurement tools. If that is the case I'll try to perform some measurements.

[Enantiomeer]

2 hours ago, efferman said:

Two Tubes are the Lowest amount of neccessary Connections at doubleworking Cylinders.

Thanks. Now that you say it like this it is rather obvious. You'd never use a singleworking cylinder for this type of machine, much too slow in the backward motion.

[Enantiomeer]

32 minutes ago, Erik Leppen said:

If you could connect a game controller to it, things will get tons more interesting. Especially if there would be a way to program the controller input. (I don't know if there are peeps from third party electronics who are doing just that?)

You mean something like this?

[howitzer]

Sariel's review really set me drooling, but sadly there's no way I can afford this set anytime soon :( Some thoughts however:

I don't really like the pneumatic tubing, though it adds detail. It feels somehow wrong to have the tubes running there but with purely cosmetic purpose. Also the ends of the tubes are ugly, as others have mentioned. Otherwise I like how there's a lot of details built into the model, it captures very well the form of the original machine.

I really love how there are lots of gears and axles turning in the arm when multiple parts of it are being operated at the same time, it really brings home the feeling of a big heavy machinery at work. Judging from the review, the software also appears to be very well polished and the features are great, something that feels quite refreshing when you've come to expect tons of release day bugs and crappy UI in new apps. No beta-testing on customers here.

I thought about the actual digging where the shovel doesn't seem to be very good at picking bricks up, but what about just using a lot more bricks? Like, dump a bucketful of mixed (not too large) bricks on the floor and you should have no problem at "digging" them. I used this technique to a great effect with the 42055 BWE, though I had a lot of problems with the conveyor belt mechanism jamming. Should have probably sorted them more carefully, to remove large/long pieces. I tried the same with 42043 Arocs but the pneumatic cylinder closing the clamshell bucket is very weak so it couldn't really push into the bricks pile to pick those up.

[Enantiomeer]

3 minutes ago, howitzer said:

I thought about the actual digging where the shovel doesn't seem to be very good at picking bricks up, but what about just using a lot more bricks? Like, dump a bucketful of mixed (not too large) bricks on the floor and you should have no problem at "digging" them.

Should work much better, especially if you mix a lot of different size/shape bricks. Probably best if you add a bunch of small combinations of 2 or three bricks/plates stuck together in irregular shapes. Those can't slide along each other so easily and therefore you can pick them up much easier. What will also help is if you use a surface that isn't smooth, like carpet or a bed-sheet. What Sariel did in his review was just a bout the worst case scenario.

If you want to be realistic you can go to a garden center and get some pebbles. Those will be quite easy to pick up. Considering the volume of the bucket, density of typical stones and the max weight the model can lift you should be able to pick up an almost full bucket of pebbles.

Disclaimer: using pebbles will scratch your bucket

[aminnich]

3 hours ago, Erik Leppen said:

If you could connect a game controller to it, things will get tons more interesting. Especially if there would be a way to program the controller input. (I don't know if there are peeps from third party electronics who are doing just that?)

What is it, the new iOS 13 that you can use a controller to play mobile games on your phone, I wonder if that could be implemented into the app for the PowerUp stuff

[Enantiomeer]

5 hours ago, aminnich said:

What is it, the new iOS 13 that you can use a controller to play mobile games on your phone, I wonder if that could be implemented into the app for the PowerUp stuff

That might work. Or a dedicated app for LEGO remote control like this one.

[pleegwat]

14 hours ago, Enantiomeer said:

If you want to be realistic you can go to a garden center and get some pebbles

I used smooth pebbles with my BWE and it worked much better than the lego pieces, at least partially because pebbles are much less bouncy.

[CSX9992]

How about using round 1x1 I have those in bulk for the bwe? Simulated gravel and it won’t damage the shovel