Second attempt, Magnum and trailers.

[Nazgarot]

I have to say it again; This is gorgeous!

What are the springs on the rear axles of the truck? And is the front suspended as well?

-ED-

[aqaz]

Nazgarot: Thank you for the compliment...

The front axle is unsprung pendular with only one plate height movement available, this was pretty much dictated by the general lack of space and the scale size of the wheel arches. However, this is more than enough.

The drive axles are floating diff frames within the confines of a chassis frame (see 'closer' folder at brickshelf) there is a vertically mounted 4 long axle from the top of the chassis at each corner of the frame that fits into the corner axle holes, in between the frame and the chassis top are springs from grey shock absorbers, the drive axles are mounted through train suspension units. Again, this came about due to lack of space, I started with just the train units (because I had some from an e-bay job lot) but by themselves they were far to soft, there was not room to mount the shock absorbers and still have the twin wheels so I came up with this. I had a lot of these grey small shockers from another e-bay job lot and I discovered that they were very easy to disassemble without breaking them, you just have to push the lugs on the inner shaft through the slots on the outer. I wanted it to behave realistically under scale loading, so if these are 15 tonne rated axles it should take 30 tonnes to fully depress the suspension, this works out at 5.79 Kilos, so now it is about right.

The suspension on the trailers is not yet finished, the shock absorbers just about carry the weight of the trailer but no load. I need something to act like air suspension between the trailing arms and the chassis base, I tried tyres but they were to hard, I have ordered some rubber 2 axle hole liftarms to try to make something with them, I am going for realism in both (scale) performance and appearance.

[Nazgarot]

The suspension on the trailers is not yet finished, the shock absorbers just about carry the weight of the trailer but no load. I need something to act like air suspension between the trailing arms and the chassis base, I tried tyres but they were to hard, I have ordered some rubber 2 axle hole liftarms to try to make something with them, I am going for realism in both (scale) performance and appearance.

How about using the small pneumatic cylinders, and hiding a automatic compressor with an adjustable pressure switch inside the trailer? All you would need is a system to change the pressure switch based on level of load, and a power connection to the truck.

I'm testing out a similar system, but with a motor controlling the pressure switch through a 24:1 gearing. when I want to raise the vehicle I simply run the motor for a short interval, and the compressor starts up again, and runs til it has the correct pressure, at the same time leveling of the vehicle at higher level. It needs a bit of work, but i have a proof of concept. Tuning rubber bands for the pressure switch is not easy, and making the system automatic should be quite a challenge... Unfortunately i have only limited time to build and design, so I will probably not get time to make a MOC with such a system. It would however be nice to see it applied in your excellent MOC.

-ED-

EDIT: Included link.

Edited May 19, 2013 by Nazgarot

[aqaz]

Nazgarot: Thank you for your interest and your input....

I follow your idea, but, I need small black 'cylinders' in the gap above the bottom of the trailing arms and they also need a second fixing point that can only move vertically.

These two trailers are static now, and it is all about looking real.... If I replaced the shockers with these cylinders I would have a load of hoses where they can be seen.

However, the next trailer but one is a semi-lowloader that will have 4 x 8 wheel axles, 4 doubles on each. The suspension is between the outer and inner pairs and cannot be seen... I thought about your idea and did a little bit of experimentation with a couple of these, it strikes me that it does not need to be so complex. It would only need to be a closed system. Under uniform loading the pistons compress the air and are surprisingly strong, but under uneven loading e.g. one wheel crossing an obstacle, its air is distributed to the other cylinders allowing the wheel to ride over the obstacle while at the same time taking the load of that wheel by forcing the others down.

​So, if all the 'top' inlets are interconnected and all the 'bottom' inlets are interconnected maintaining a partial vacuum and minimising air escaping the system this would seem to work, I need to do a lot more to firm up what I am saying here but I am tired now and getting some outside interference from someone who: 'thinks I am mad and should be asleep'.... It is not just doing the Lego that reminds me of 50 or more years ago....

However, I might try this on the inside of the existing trailer chssis' when I have tried it on the new trailer.....

[Nazgarot]

Using pneumatic cylinders with all inlets and all outlets interconnected is a well know use for suspension systems. For your use I think this will work very well, but it does not have the adjust-ability of the system i suggested. I was thinking of how this could be realized before i got to sleep yesterday, and will make a new proof of concept. I may post it as a new thread when it's done if i can find the time.

I am very interested to see your implementation, so please keep up the good work, and keep us updated.

-ED-

[aqaz]

'Well known'..... I expect all the things I think up will have been done before, I have been away so long, and just returned to all these new parts....

But yes, I will post my new trailers as they are completed... 4 more planned at this stage.

I still can not get into MOCpages, can anyone help with this?

[technicfan]

Very nice job. Is the flat deck trailer strong or quite flimsy?.

[aqaz]

technicfan: It is stronger than it looks, this is a scale loading of 27t. (I mention elsewhere that the suspension is not finished on the trailers, so the deck is touching the wheels and it will not move. )

[Someonenamedjon]

Ouch... I can see that bend at the end...

[aqaz]

Yes Jon... Just like a real one does.