18 replies to this topic

[dr_spock]

Greetings.

My 8258 Crane Truck looked like it should be towing something.  After surfing around heavy transport world (http://www.heavy-transport-world.de) for some ideas, I freelanced a trailer for my crane truck. It is 70 studs long and 18 studs wide.  The low flat bed is 6 studs off the ground.  I don't have a part count as I built it on the fly and wasn't counting at the time.  The hardest part is my lack of Technic parts and skills.  My future plan is to acquire more parts and make it bigger when finances permit.  I would also like to figure out how to make some of the wheels self-steering.

[5150 Lego]

Looks great! Do the wheels steer?

[Sergiu]

Very good MOC. The design is quite good and it makes a great pair with the Crane Truck, although if you intend to transport vehicles on the trailer, I think you should add a ramp.

[Alasdair Ryan]

[quote name='dr_spock' date='Jan 16 2010, 05:38 AM' post='662084']
Greetings. I would also like to figure out how to make some of the wheels self-steering.

here is a way if you make the lorry pf fuctioned you get your trailer pf fuctioned then you take an extention cable from the front left of truck to the back right of the trailer, and the right of lorry to the left of the trailer.

another way is to wire the truck and trailer sepertley this woud make it with no cables between the truck and the trailer

Edited by Alasdair Ryan, 16 January 2010 - 02:08 PM.

[Jetro]

Your not the only one who thought the truck needed a trailer, although mine is still in the planning stage. I was thinking to include mechanical steering based on the angle between the truck and the trailer. First I need to find enough space to be able to build it though...

The design is quite nice and looks especially good with the excavator on top. Next up: ramps!

[Enilder]

 Jetro, on Jan 16 2010, 01:34 PM, said:

Your not the only one who thought the truck needed a trailer, although mine is still in the planning stage. I was thinking to include mechanical steering based on the angle between the truck and the trailer. First I need to find enough space to be able to build it though...

The design is quite nice and looks especially good with the excavator on top. Next up: ramps!

+1. i think it's a very nice truck!

[dr_spock]

Thanks guys.

Alasdair, the PF steering is an interesting idea.  I need to get some PF motors.  

Jetro, do you know if there are instructions available for mechanical linkage steering somewhere?

I don't have parts for ramps yet but it appears that ramps can be optional for an excavator.  It can load and unload itself without ramps.  





Pretty neat.  

[Jetro]

 dr_spock, on Jan 19 2010, 07:25 AM, said:

Jetro, do you know if there are instructions available for mechanical linkage steering somewhere?

Not that I know of, but if you understand the principle it shouldn't be too hard to implement.

[Alasdair Ryan]

i might be able to make some instructions for the steering if you want or ramps ,just give me a size

[dr_spock]

Thank you very much for the offer, Alasdair.  I think I managed to figure it out.


After a lot of trial and error, I have put together a working steering assembly for the trailer. The steering is controlled by the round yellow warning light in the back, aka hand of God steering method.  Push it in turns the wheels one way, pull it out turns the wheels the other way.



I've also test-fitted a couple of ramps. I ran out of long black plates but some white ones were available.  I don't think it looks too bad with white.

[Enilder]

 dr_spock, on Jan 21 2010, 11:45 PM, said:

Thank you very much for the offer, Alasdair.  I think I managed to figure it out.


After a lot of trial and error, I have put together a working steering assembly for the trailer. The steering is controlled by the round yellow warning light in the back, aka hand of God steering method.  Push it in turns the wheels one way, pull it out turns the wheels the other way.



I've also test-fitted a couple of ramps. I ran out of long black plates but some white ones were available.  I don't think it looks too bad with white.

sorry for my ignorance but why do you need steering for the trailer? i've not seen a trailer with steering mechanism. maybe i should look at rl models more carefully(?). thanks in advance.

[Sergiu]

Enilder, some trailer have steering in order to be able to steer in a smaller place than usual, but also to reduce tire wear. This type of trailers is quite rare, so this is probably why you didn't see any.
dr_spock, the trailer looks very nice with white ramps and you did a good job with the steering but I think that it would have been even better if you could have managed to make the wheels steer automatically, not by hand. I think this is the way real trailers work, but this is just my opinion.

[dr_spock]

Enilder, here is a link to a company that make self steering trailer systems.  http://www.v-s-e.nl/home.html?L=1   Their system can steer automatically or manually by the driver with a remote control.  They have videos of how it works.  

Sergiu, I haven't figured how to do it automatically yet.   That's still work in progress.   Maybe something that attaches to the 5th wheel/king pin or Alasdair's idea of PF motor if I also motorize my 8258 crane truck steering.  So far this little MOC has been a good learning experience.

[Enilder]

thanks!

i am guessing you can automatically do trailer steering with remote control. sort of like upcoming 2010 excavator where 2 remotes (4 functions) held together and use proper gearing to steer trailer while steering front. i wish i can go back home now!!! :(

[Sergiu]

 dr_spock, on Jan 22 2010, 10:11 PM, said:

Sergiu, I haven't figured how to do it automatically yet.   That's still work in progress.   Maybe something that attaches to the 5th wheel/king pin or Alasdair's idea of PF motor if I also motorize my 8258 crane truck steering.  So far this little MOC has been a good learning experience.

I was actually referring to a steering system with springs or rubber bands, something similar to a return-to-center steering, so the wheels turn only when the friction with the road is big enough. I hope you understand what I said.
However a remote controlled steering system seems pretty interesting too.

[Enilder]

 Sergiu, on Jan 23 2010, 03:27 AM, said:

I was actually referring to a steering system with springs or rubber bands, something similar to a return-to-center steering, so the wheels turn only when the friction with the road is big enough. I hope you understand what I said.
However a remote controlled steering system seems pretty interesting too.

only concern with the rubber band method is the residue that the rubber band leaves on ABS material. (well i guess in general)

[Paul B]

That is a great MOC to add to the crane truck model, it looks like it works really well and I feel it adds on to the truck and looks just right.

Paul

Edited by Paul B, 24 January 2010 - 11:47 PM.

[Blakbird]

I really like the concept of adding a trailer to this model, and this is a very good looking and well designed trailer.  To me though, it seems too small for scale.  When I look at it attached to the truck, the trailer is no longer than the truck and I imagine a full size trailer being twice as long as the truck (maybe 52 feet?).  This was probably just a constraint of the size wheels you had available.

[dr_spock]

Sergiu, I understand what you mean by using rubber bands for self-centering steering of the wheels.  

Thanks Paul B.  

Blakbird, thanks for the feedback.  I kept it short so that the crane and trailer will fit on my display shelf.   Extending it wouldn't be too difficult since the trailer design is modular.  Each 2 axles is its own section.   They are held together by pins and plates.   It can be turned into a Euro low loader with 4 axles in the back and 2 axles in the front and a low platform in between.   It can also be turned into a longer semi-low loader by adding a section between the goose neck and first section.