[MOD] 42042 Fully motorized Cable Excavator

[McMarky]

Hi everybody,

I'd like to show you my version of 42042 MOD.

Features:

• fully motorized,
• still one motor only,
• independent tracks,
• cable operated clamshell,
• LED.

How do you like it?

and movie on the YouTube:

https://youtu.be/BJQNFuPhOg4

 

 

Edited May 20, 2021 by McMarky

[J159753]

That's brilliant! Redoing this set has been on my to-do list for ages, but I hadn't planned anything quite so slick! Please do a photo tear-down when you take it apart...

[Bartybum]

Man, I really love these tracked vehicle MOCs where the steering is controlled through levers. I really wish TLG would do this for official sets

[Jurss]

This is true Technic.

[Pattspatt]

Very cool! Love how elegant your clamshell design is, and your expanded gearbox works great! 
 

I want to make sure I understand how the clamshell works. I know it’s on two reels, and that operating the reels simultaneously raises/lowers the bucket, and operating one reel at a time opens/closes the bucket. I can’t work out the pathway of the strings, though. 
 

I assume both reels have separate strings, one end of each string attached to each reel. Where are the other string ends attached - both to the blue/white 3L beams? Could you show the inside of the clamshell’s “tackle block”?

[ColletArrow]

I agree with both of the above comments! You've made some fantastic modifications to an already highly-functional set, and I too would love to see a cable-routing diagram for that bucket. Everything seems to work so well, excellent work!

[McMarky]

Thanks for your positive response. 

2 hours ago, Pattspatt said:

I want to make sure I understand how the clamshell works. I know it’s on two reels, and that operating the reels simultaneously raises/lowers the bucket, and operating one reel at a time opens/closes the bucket. I can’t work out the pathway of the strings, though. 

Yes, you are right. Operating the reels simultaneously raises/lowers the bucket, and operating one reel at a time opens/closes the bucket lowering/raising it at once.

If you want to open/close the bucket in place just run reels in opposite direction.

2 hours ago, Pattspatt said:

Where are the other string ends attached - both to the blue/white 3L beams? Could you show the inside of the clamshell’s “tackle block”?

Yes, the strings are attached in the blue/white 3L beams.

1 hour ago, ColletArrow said:

I too would love to see a cable-routing diagram for that bucket. Everything seems to work so well, excellent work!

There is an ad hoc made scheme:

Dots mean mounting points. The strings are just jammed with pins in 1x3 lift arms.

And a simple pulley inside the clamshell:

 

[Johnny1360]

Funny how this thread appears out of the blue, right when I have been looking at this set on my display cabinet. Been trying to decide whether to break it down or modify it some, it has sat there so long.

I really like what you have done with the bucket and since I have the parts, I think I will try your setup, simple yet excellent playability, thanks. I never really liked the original bucket but was always to lazy to mod it, lol. One question though, what string to you use?

Also always felt the boom should be longer as well but then the string is simply to short to do much with it. Plus I think then some weight needs to be added to the back of the cab, unsure what to use but I would like for it to be a LEGO solution.

Anyway really like what you have accomplished and thanks for the inspiration, the thing I seem to be lacking in the most anymore.

 

[jorgeopesi]

Very cool  .

[suffocation]

Awesome mod! I'd love to see some pics of the internals.

[Pattspatt]

2 hours ago, McMarky said:

Dots mean mounting points. The strings are just jammed with pins in 1x3 lift arms.

Thanks very much for the diagram! Very educational. Looks like it’d theoretically be possible to have two strings instead of three, by having the blue string (in the diagram) continue through its mounting point and replace the red string. Your solution has very nice visual symmetry, though - I can’t think of a way to have the best of both worlds.

[Bartybum]

I’d love to see how you routed two inputs through the turntable for the treads. I really want to try this when I get back to building but I’ve never managed to understand it properly

[MangaNOID]

nice work. I have to comment on the 42042!

I was just about to show an update on mine that I finished so seeing this is great! I like the bucket very much! I may even switch to your bucket setup as the motorised claw doesn't pick much up really which is no fun...ah... for the kids ya know.

do you still use the L motor?

I cannot seem to get enough power to use the L motor anymore for independent track driving after switching to similar manual setup with single motor. I think my motors got wet a bit at sometime so that may be my problem 

[McMarky]

12 hours ago, Johnny1360 said:

Funny how this thread appears out of the blue

To make it even more funny, I tell you that I've MODed it just by the way! Currently I'm building an RC PoweredUp cable excavator and waiting for additional motors I bought used 42042 just as a parts donor. :) I built it and started to experiment with clamshell and reels. And finally, I have got that MOD. :)

12 hours ago, Johnny1360 said:

what string to you use?

This one:

https://sklep.ariadna.com.pl/75-heros

It's braided polyester thread 1mm. It looks and behaves like the LEGO one. It's difficult to tell them apart.

12 hours ago, Johnny1360 said:

I think then some weight needs to be added to the back of the cab

Yes, if you want to lift heavy loads. But for excavator it's unnecesary.

12 hours ago, Johnny1360 said:

Anyway really like what you have accomplished

Many thanks :)

11 hours ago, Pattspatt said:

Thanks very much for the diagram! Very educational.

You're welcome. I'm glad that it helped.

11 hours ago, Pattspatt said:

Looks like it’d theoretically be possible to have two strings instead of three

Yes, I've experimented a lot with strings. I even used the jammed green one, without the blue one. But it was impossible to change anything without unwinding the string from the reel. So, I cut it.

7 hours ago, Bartybum said:

I’d love to see how you routed two inputs through the turntable for the treads.

There are a few pics of my colorful prototype :)

 

 

 

2 hours ago, MangaNOID said:

nice work.

Thanks :)

2 hours ago, MangaNOID said:

do you still use the L motor?

Yes, and it has enough power for my model.

[u118224]

This MOD makes me want to buy 42042. How many Technic sets is too much?