Logging Truck and Trailer MOC - Need Help

[DarkShadow73]

Hi-

I built a large high-deck trailer (not a low-boy), semi tractor-trailer size, to hook up to my Logging Truck (the set 9397). I constructed it with pendulum type suspension on the 2 sets of rear dual tires on the back of trailer. I built it out of 11x5 black panels and beams to reinforce under it, between the decking pieces and also on the sides of the deck panels and front to slide over the chassis of the logging truck. Additionally, I added landing gear and a pin drop type hookup to a fifth wheel I added on the logging truck itself.

My trouble is the front 1/3 of the trailer droops some and when trying to hookup to the tractor (the modified logging truck) the drooping deck front won't slide right onto the chassis of the logging truck's fifth wheel. The fifth wheel setup is similar to the fifth wheel found on the hook crane variation of the 8436 Truck. I have reinforced the bottom the trailer with beams across the width of the trailer and also lengthwise, but yet it still droops. I wish I had pics of the trailer and the problem but the digital camera doesn't work right now, and my cell phone won't connect to a usb on my pc.

Without seeing the problem, do you guys have any advice?

EDIT: Some additional info: I added some 15L beams at the front of the trailer. The trailer does clear the chassis of the logging truck, but once it hits the perpendicular part with the axle hole/pin hole for the 3L axle with endstop it won't go any further due to the sagging of the front of the trailer. If I manually lift the front of the trailer and slide it on everything's fine, but due to the realism of backing the tractor under the trailer this really bugs me...

Edited July 21, 2014 by DarkShadow73

[Alasdair Ryan]

The simple solution would be to use two layers of studded beams and plates.

[Bricktrain]

how wide is the trailer, I use two rows of beams between the panels and then another row each side of the panels, but that makes it 21 studs wide.

[DarkShadow73]

The simple solution would be to use two layers of studded beams and plates.

@ Alasdair - when you say 2 layers, do you mean under the decking, use beams downwards? My biggest issue is I don't have many studded beams, and hardly any in black (colour of the trailer). I have taken off the wheels in back and have lowered them 1 stud down to raise the height of the trailer, but its the sagging in front that bugs me and makes the tractor unable to slide under the trailer, and the trailer is the perfect height to go over the simple 5th wheel on the tractor, but not when its detached.

how wide is the trailer, I use two rows of beams between the panels and then another row each side of the panels, but that makes it 21 studs wide.

@Bricktrain - the trailer is 15 studs wide, I checked the wheelbase width on the finished logging truck and it was exactly 15 wide. I use liftarm beams crosswise underneath the deck, and a whole line of beams lengthwise under the trailer deck liftarm beams crosswise underneath the trailer and between the deck panels on top I use 3 wide lengthwise between each set of panels, and crosswise between the deck panels I use 2 sets of 15L liftarm beams. Decking is nearly identical to the construction of the 8063's trailer. I suppose as Alasdair mentioned I could use a 2nd set of beams, but without enough studded beams might have to buy thru Bricklink. I have 1000's of spare parts, so figured I'd use what I had and it would be sufficient. I do believe some of the trouble is ahead of the decking I also have 8 15L liftarm beams pinned together and being non-studded beams there is no way to reinforce those beams underneath....ahhh

On another note...that is one very nice truck and trailer you have there...that was my next project was a low boy to fit the 8043 Excavator, it needs a very wide deck indeed.

Edited July 21, 2014 by DarkShadow73

[Alasdair Ryan]

@ Alasdair - when you say 2 layers, do you mean under the decking, use beams downwards? My biggest issue is I don't have many studded beams, and hardly any in black (colour of the trailer). I have taken off the wheels in back and have lowered them 1 stud down to raise the height of the trailer, but its the sagging in front that bugs me and makes the tractor unable to slide under the trailer, and the trailer is the perfect height to go over the simple 5th wheel on the tractor, but not when its detached.

Yes that would be ideal,but you could try using studless beams (three studs high sandwich).

[Bricktrain]

Some ideas for you. I havent shown all the pins, but Im sure you can add those.

trailer.lxf

[DarkShadow73]

Some ideas for you. I havent shown all the pins, but Im sure you can add those.

Couldn't open your lxf file, but I did take all ideas given to me and I made it work. Its a long beast for sure with the trailer, probably around a meter long but it looks great. Only thing I did to the tractor itself was not install the log sides and just designed a simple 5th wheel. I even built the crane to help offload pipes, etc, from the trailer bed. I'm not nuts about the way the crane folds up, but it works. Think maybe another project is to remove crane and using the same gearing I might install a winch.

Thanks again for your input guys.

Yes that would be ideal,but you could try using studless beams (three studs high sandwich).

That idea did make it a lot more sturdy and since I had 1000's of spare parts I had plenty of studless beams. I also raised up the landing gear 1 stud as well to get the height I needed without compromising the look. Once I raise the landing gear if you look straight on you can it tractor/trailer are nearly level with each other.