42055 - Bucket Wheel Excavator - MODs and Improvements

[Blakbird]

On 3/1/2017 at 3:50 PM, Gabi_BC said:

question: is it possible to set the motor RPM via the sbrick app such as to eliminate the need to build a reduction gear? 'cause if so, i'm considering switching all the control system to sbrick

Yes, you can do that in the profile editor for SBrick.  Of course, you will have a lot less power if you slow a motor down versus gearing it down.

[Ngoc Nguyen]

ULTIMATE MOD for 42055 B model (or so I believe).

The mods include:

1/ Improve the short conveyor belt
2/ Increase chute shaking rate without removing clutch gears

without using too many extra parts.

-------------------------

1/

- Problems:

1.1/ The short conveyor belt is too low, so the mining truck doesn't fit under it.
1.2/ The side panels are too short, so the bricks sometimes fall out before reaching the end of the belt.
1.3/ The slope leading from the filter is too long, so the bricks sometimes stay on it without falling to the belt.

- Fixes:

-----

1.1/ Attach the 5M liftarms at the second stud instead of the first one.

 

-----

1.2/ Replace each 3x11 panel covering the tracks with 2 15M liftarms, 1 11M liftarm, and 2 of this http://brickset.com/parts/4210851

The original setup is 

3L liftarm - 3L connector - 3x11 panel - 3L connector - 3L liftarm

 

Replace that with this setup

15L liftarm
15L liftarm
2L connector - 11L liftarm - 2L connector

Doing that will give you two spare 3x11 DBG panels. Now use them to replace the two 3x11 dark blue pamels in this step

 

Now you have two spare 3x11 blue panels. Now attach them to step 372 and you've got the short belt fully covered.

-----

1.3/ The original slope is 11L long:

Use a 5x7 frame, fill it inside with 3 5L liftarms, and attach to one end 2 5L liftarms, and you will have a slope that is 9L long. However you can only attach the frame at the 2nd hole, so the effective length is 8L, the shortest possible length for the slope. If it's shorter then the bricks will fall back into the gap below the slope.

------------------------------

2/ The general idea is to increase the gear ratio from the motor to the long belt only, and reduce the gear ratio to the short belt and the intake belt. If you only do the former part without doing the latter part, it will increase the speed of the whole drivetrain system, which eats more power from the motor, which makes it barely faster than the original setup. 

But first of all you need to increase the number of pallets on the track links. In the original setup there are 11 5L arms. I would suggest you double them into 22 liftarms, but 22 3L liftarms. If you use 22 5L liftarms the weight of the track will increase significantly, and thus reduce the speed.

-----

To increase the gear ratio from the motor to the long belt,

In step 169, DO NOT attach the black brace. The gear ratio of the brace is 1:1. Instead, attach a 20z gear + bush +  7L axle. In the yellow 5L liftarm, push the 12z gear to the outermost, and attach it later. This will give it a gear ratio of 5:3.

-----

To decrease the gear ratio to the intake upper belt:

 

Replace the 5L liftarm with a 9L liftarm in step 136

 

Replace the.13L liftarm with the 5L liftarm in step 142.

The general idea is that, instead of attaching the 3 16z gears that lead from the motor to the long belt on the right side, you move them to the opposite side.

Put the 16z gear on the other side

 

Put the red clutch gear on the other side

 

 

Insert a 12z gear in the place of the 16z gear, and insert the 16z gear on the other side. 

 

Replace the 16z gear with 20z gear. 

-----

To decrease the gear ratio to the short belt:

Replace the 16z gear with a 12z gear in step 292

 

Replace the gears in step 422 with, from up to down, 20z - 12z - 20z

 

Replace the gears in step 390 with

12z - 20z
         16z - 16z

 

I've made all these mods in my own model, and the result is quite satisfying. Although I still have to shake the bricks out sometimes, the chute shakes very rapidly, about two shakes a second.

Edited March 5, 2017 by nguyengiangoc

[Imanol BB]

That is a really cool and very unexpensive MOD, and seems you really focused your mind in that because you have given a very deep explanation of the MOD and how to implement them, even when the whole filtering and transporting process might not be 100% effective, it is enough good for it, even real and precise machines can´t make to 100%, i imagine that those MODs have surely improved the model, i wish i could get one i a future and try them, thanks for sharing.

[Nico15]

I'm just finished the A model but I'm not really satisfied about the movements. Buckets move really slowly and jerkily, like other model I saw on YouTube.

I read all of your posts looking for improvements but they are too invasive for me. Many add several power units and rc controllers but I prefer to let the gearbox quite the same. I have not a clear idea yet, other models I have work well and I have never though to improve a model, so I have no experience.

Maybe a second power near the gearbox or "inside" the bucket wheel activated by the gearbox. Have you ever though something similar or other suggestions? Thanks

[Ngoc Nguyen]

1 hour ago, Nico15 said:

I'm just finished the A model but I'm not really satisfied about the movements. Buckets move really slowly and jerkily, like other model I saw on YouTube.

I read all of your posts looking for improvements but they are too invasive for me. Many add several power units and rc controllers but I prefer to let the gearbox quite the same. I have not a clear idea yet, other models I have work well and I have never though to improve a model, so I have no experience.

Maybe a second power near the gearbox or "inside" the bucket wheel activated by the gearbox. Have you ever though something similar or other suggestions? Thanks

Step 506 507 508 in the instructions.

 

Instead of
20z 12z
       24z 8z
       24z 8z

in the original setup, rearrange them as

24z 8z
24z 8z
      12z 20z

20z: the tan gear, 20 teeth
12z: the black gear, 12 teeth
24z: the white gear, 24 teeth
8z: the grey gear: 8 teeth

I have this set up in my own model, so I can guarantee that it works smoothly.

This increases the speed significantly, while still allow enough force to not slip the clutch gear 24z. You can even change the 12z - 20z into 24z - 8z and the clutch gears still don't slip, but that would be too fast to be enjoyable.

[AFOLegofan66]

this is the first time I have looked at this fantastic BWE from this perspective I have the kit but have had no time to get to it!! I got the lxf file and will try the full mod of this and all the fixes. Now what to do first the A or the B model?  Thanks for all the great ideas and the LXF of course. I'll be using blueprint and bluerender for this build and Sbrick for control. I'll keep you posted..

[Nico15]

4 hours ago, nguyengiangoc said:

Step 506 507 508 in the instructions.

Instead of
20z 12z
       24z 8z
       24z 8z

in the original setup, rearrange them as

24z 8z
24z 8z
      12z 20z

20z: the tan gear, 20 teeth
12z: the black gear, 12 teeth
24z: the white gear, 24 teeth
8z: the grey gear: 8 teeth

I have this set up in my own model, so I can guarantee that it works smoothly.

This increases the speed significantly, while still allow enough force to not slip the clutch gear 24z. You can even change the 12z - 20z into 24z - 8z and the clutch gears still don't slip, but that would be too fast to be enjoyable.

Thanks for your suggestion. I tried that configuration but things went bad...the clutch slip all the time so the problem wasn't the velocity but the resistence of the buckets mechanism.

I paid attention on all the gears through the steps, I know huge model are very sensible to this but I miss something. I will re-assemble from 6th packages.

[Nico15]

I noticed that the huge bucket ring is not so rigid, resulting in a continuous distortion while rotate. I'm thinking to mount the 12z gears on springs in order to have a better connection and limiting the distorsion.

What do you think about that? Can it help a bit?

Edited March 14, 2017 by Nico15

[allanp]

On 1/27/2017 at 11:15 AM, designer-han said:

Just being in the process to build the BWE from my spare part collection. I was wondering if some of you run into the next to 'issues' as well.

1) I used initially the DBG treads of the 42042 Crawler Crane, and experienced a very jerky run (including stalling) of the treads over the sprocket wheels. This has all to do with inner tread shapes (bad = triangle based, smooth = square based).
I know that TLC changed a couple of years ago the tread design; but I did not expect that the Crawler Crane treads of 1 yr before the BWE should fail. I used the older treads I had, and no issues at all.
My questions is: what are the shapes of the official BWE DBG treads??

2) The conveyer chain of the BWE (upper chain, from buckets to middle section) to jam once in a while. I guess this has to do with the older DBG treads I am using (have more slack). Does anyone experienced this as well?

 

I had this problem too building it from my own parts so I extended the beam that it gets jammed on with a 5x0.5 lift arm to eliminate that edge. it's a tight fit but it does fit ok.

[curakar]

Hello everybody....this is my modification....it is only cosmetic 

[marini]

On 02/03/2017 at 0:50 AM, Gabi_BC said:

I'm back

question: is it possible to set the motor RPM via the sbrick app such as to eliminate the need to build a reduction gear? 'cause if so, i'm considering switching all the control system to sbrick

question2: is there a limit to what bluerender can take until it tells you to leave it alone? 

Happy spring everyone!

 

Hello Gabi_BC

Here is the video of the 42055 XXL edit

Good reading
Https://youtu.be/8G63VV4i3MQ

[Gabi_BC]

oh my, this looks amazing

congrats!

[OneMoreRobot]

6 hours ago, marini said:

Hello Gabi_BC

Here is the video of the 42055 XXL edit

Excellent work Marini - the XL version looks & works so well congratulations. 

OMR

[Imanol BB]

That BWE looks really cool, the clam shell buckets actually look good on it, and i imagine that they might enhance the digging ability, i hope to see more videos of it digging some bricks, i like it a lot; by the way, while watching the video i found another one of a Lego Expo in France, and i found another pretty cool BWE, i would like to know more about it but i am not sure if the designer might be a member of this forum, and since this model suits this topic perfectly, i felt it was worth to share, look at minute 1:35

 

Edited March 21, 2017 by Imanol BB

[Gabi_BC]

Just now, Imanol BB said:

the clam shell buckets actually look good on it

I only used them in LDD because the real 42055 ones were not available in the program 

[Imanol BB]

1 hour ago, Gabi_BC said:

I only used them in LDD because the real 42055 ones were not available in the program 

I didn't knew it, i think that they actually look good, and because they are wider and don't have teeth they might work better for digging small Lego pieces and materials, and they would have more capacity, thus the model would move more material without the needing of speeding up the bucket wheel; and i actually like the color of the clam shell buckets (black), maybe it doesn't suits the yellow-blue-grey pattern of the whole machine, but for some reason i like them, by they way, how is your LDD model coming up so far, have you made any progress on the rear conveyor belt?.

[Rygar]

Gabi, your BWE is wonderful.

It would be awesome to see it on rebrickable.

[Rolando]

I've build the BWE with 3xSbrick, 3 L-Motors, 3 M-motors, 1 XL-Motor and 4 PF-LEDs. 

My children (and I as well) love to play with it. ?

 

[Imanol BB]

Nice MOD, everything seems to work pretty well, do you have more details of all the modifications you did?, is nice that there seems to be just minor external changes and still it performs well.

[Rolando]

Well, in the base I've installed 3 L-Motors. 2 for driving the tracks and one I've used to drive the rotation of the turret through the center of the turn table. An AA-Battery box and 1 Sbrick is placed in the base aswell.

For the "off loading belt", the rotation of the "off loading belt" and driving both linear actuators for adjusting the height of the bucket wheel I've installed 3 M-Motors in the backend.

The second sbrick is installed at the side of the turret.

On the top a the XL-Motor just drives the wheel as in the original design. It still doesn't run really smoothly (which I guess I caused by the track belt and the mounted 5L-Liftarms. The 3 Sbrick is placed here. 3 PF-LEDs are connected to this one as well.

[Nico15]

Just finished to re-build the A model but it was useless: the bucket wheel doesn't work well. There is nothing to do, its a structural problem due to the huge weight and the jaws of the 4 rack pieces.

Then I decided to let the XL-motor to drive all the mechanism except the bucket wheel. Most of you installed a L-motor just inside the wheel but it's not more avaible on Lego Shop while one the external sites it's too expensive (~20€).

The M-motor has the same dimension and is quite similar in terms on torque and RPM. Can you confirm this? If yes I will buy the M one, otherwise I'll pick the XL-motor (Lego Shop sells it at only 12€).

[Bartybum]

On 14/03/2017 at 4:25 AM, nguyengiangoc said:

Step 506 507 508 in the instructions.

*snip*

Instead of
20z 12z
       24z 8z
       24z 8z

in the original setup, rearrange them as

24z 8z
24z 8z
      12z 20z

20z: the tan gear, 20 teeth
12z: the black gear, 12 teeth
24z: the white gear, 24 teeth
8z: the grey gear: 8 teeth

I have this set up in my own model, so I can guarantee that it works smoothly.

This increases the speed significantly, while still allow enough force to not slip the clutch gear 24z. You can even change the 12z - 20z into 24z - 8z and the clutch gears still don't slip, but that would be too fast to be enjoyable.

Can you not just replace the 24z clutch gears with normal 24z gears?

Alternatively, can you not do:

24z   8z

24z   8z

        20z   12z

...?

Edited March 31, 2017 by Bartybum

[Ngoc Nguyen]

@Bartybum

- The point of using clutch gears is to prevent damage when the conveyor belt is stuck. Using the normal 24z gears can twist the axles or break the 24z gears. Mine were broken when the XL motor tried to wind them.

- Setting up as you said:

37 minutes ago, Bartybum said:

24z   8z

24z   8z

        20z   12z

would not change the speed of the belt at all.

Recall that the original setup in the instruction is:

20z 12z
       24z 8z
       24z 8z

Both setups reduce the speed by (12/20) x (8/24) = (3/5) x (1/3) = 1/5 = 0.2, regardless of order of gear pairings.

The setup I suggested is:

24z 8z
24z 8z
      12z 20z

This setup first increase the speed, then decrease it, so that the final speed is faster. The calculation is (20/12) x (8/24) = (5/3) x (1/3) = 5/9 = 0.55.

[Bartybum]

@nguyengiangoc

Man what a poorly designed power train the designer made :| I have two ideas... one involves adding a third 24z 8z pair, and the other involves rubber bands

Edited March 31, 2017 by Bartybum

[The_Icestorm]

I managed to create a MINDSTORMS version of the BWE, a few months ago. The model uses an EV3 brick and PF to control the BWE and an NXT for the mining truck.

2 EV3 medium motors control the drive and super-structure rotation, and 2 EV3 large motors control the boom-arm elevation and lower conveyor belt swivel. A PF large motor controls the main conveyor/bucket wheel, and a PF medium motor controls the lower conveyor. The truck is driven by 2 NXT motor, one for drive and one for steering.

More info here: https://www.us.lego.com/en-us/mindstorms/community/robot?projectid=3e125a5b-475c-4a4c-b3ed-e4b4f2192907