Thread: Tandem Suspension Concept

nope airbags'll do that for ya.

Whats really fun is when you join the front and the rear on the same side together Boy does that allow for some great articulation.

Thanks muchly for all input.
Essentially the task at hand boils down to whether I want the hassle of running such a heavy boat offroad (5m glass wahoo).

Tandem, although heavier will reduce point loadings in the soft stuff. With tandem I would run smaller wheel/tyres (14"LT). Which has benefits of keeping the hull closer to the deck for beach launching.

The rationale for the above design was keeping as much suspension stuff out of the salt.
The camelback leaf setup would rust as quickly as most other leafies!

Other option is to simply run a single axle with triangulated 4link as I have done in the past. Maybe Im just a little precious - plenty of 1tonne-ish single axle camper trailers trundling around.

Hmmm

Steve

Originally Posted by roverrescue

The rationale for the above design was keeping as much suspension stuff out of the salt.
The camelback leaf setup would rust as quickly as most other leafies!

Steve

How about 2 leaf Parabolics? Don't seize up with rust like multileaf semi elliptics.
Bill.

Parabolics can give a more....elegant ride too

Originally Posted by roverrescue

Thanks muchly for all input.
Essentially the task at hand boils down to whether I want the hassle of running such a heavy boat offroad (5m glass wahoo).

Tandem, although heavier will reduce point loadings in the soft stuff. With tandem I would run smaller wheel/tyres (14"LT). Which has benefits of keeping the hull closer to the deck for beach launching.

The rationale for the above design was keeping as much suspension stuff out of the salt.
The camelback leaf setup would rust as quickly as most other leafies!

Other option is to simply run a single axle with triangulated 4link as I have done in the past. Maybe Im just a little precious - plenty of 1tonne-ish single axle camper trailers trundling around.

Hmmm

Steve

If you are going to run in salt water regularly you are going to get rust no matter what preventative measures you take. The available coatings only delay the inevitable.

Have a look at Chalmers or Mitchell suspensions. They are load sharing and use rubber springs. As there is no friction damping from leaf springs, they need shock absorbers.

Get your drawing (key)board out.

Certainly a possibility.
I like the simplicity of the camelback design.
There is a springmaker in Cairns... spose I could make a trip to the big smoke - seems a little excessive though Brad could probably organise 2 leaf para-whatevers!!!

More red to be drunk before deciding!!!

S

Someone on another thread mentiond modern Transit Vans have Paras on the back. I run single leaf Paras on the back of my series 2 Bitsa. They are off early Transit front axles. You could double them up if necessary. The 'walking' action of this design gives a relatively smooth ride even if the springs are a bit rusty. As an example, the chassis of a single axle trailer with rusted/seized springs will rise vertically a distance of 100mm when riding over say a 100mm bump. With centrally pivoted load sharing 'walking' type suspension the chassis only rises 50mm.In fact, there have been a few trucks and trailers built with unsprung walking beams pivoting directly off the chassis.

I was looking at the Bell crank horizontal coil front suspension on an old Rover 2000 P6 the other day, and it reminded me of the tandem rear suspension of a World War 2 German Kruppe 6x4 truck. A bell crank on each axle on each side, pivoting from the chassis were inteconnected by a single horizontal coil spring.
Bell crank type radius arms could be welded up from old RangeRover bits, but you would then need Panhard rods for lateral location.
Bill.

As well as the feedback given already, I think it's all well and good to have the springs load-sharing, but dampers should be between the axle and the chassis. Just stops one more potential shake.