Hi folks. I'm sure this has been covered many times, so rather than lengthy explanations please point me at other posts or resources.

I need to build a reasonable sized tank track and base, I'm not interested in a realistic model, this will be to carry a camera outside, so smooth suspension is more important than form.

I've searched YouTube, and while there are some good looking examples there are very few helpful instructions, to carry weight, maintain strength etc.

Any help would be very much appreciated.

Thanks.

How heavy of a weight are you planning to carry? Usually torsion bars will permit a smooth ride and are relatively low profile, but Here are some other older designs that I have posted some photos of, I have devised some more realistic suspensions since the page was created.

http://www.mocpages.com/moc.php/383492

Here's a recent guide to basic suspensions that kelkschiz made.

The first important thing for building a smooth suspension system, is building light. The lighter you build the smoother the suspension can be. Building light and strong requires a frame strengthened by crossbeams or something that does the same job. Take a look here to see an example of what I mean.

The second important question is which suspension type to use. In your case I would pick a christie suspension or a very soft torsion bar suspension. You can get a very soft torsion bar suspension just by making the torsion bars longer. If you go with a christie suspension you should probably use the 9.5L springs; power of the spring depending on the weight of the model. If you can build it light enough, the soft spring would probably be best. The rollers placed close to each other, while still retaining full range of motion. Placing the rollers closer to each other also allows softer springs to be used than would otherwise be the case. If you want to go cheap or want to build a small model then rubber bands are a good option to replace the LEGO springs. An advantage of rubber bands is that you can easily adjust the tension strength. Which makes experimentation easier.

Building a very smooth tank suspension is an art, it will probably take some experimentation to get all the factors exactly right.

Thanks for the responses folks, the spring system is the one to go for, I have a huge bag of the large shocks so I might as well use them for something!

When I come up with a working system I'll post some pics. :o)