EDIT Professional instruction now available for sale : You can email me at setechnic@gmail.com /EDIT Hello, Let me introduce a MOC I designed 2 months ago : a UCS Hailfire Droid. UCS Hailfire Droid by Anio, sur Flickr UCS Hailfire Droid by Anio, sur Flickr The model is made out of about 1,070 Lego parts. The big rings can rotate so that the vehicle can drive. The model has a lot of details : - missiles on the top - the red eye and the mandible - rotating cannon below - fake cylinders on the "arms" - some details in textures : small greeebles, tiles/studs, small dark brown areas - the blade suspensions, with flexs and road signs (!) - the details of the motors, reproduced with SW printed dishes. The building process started with the rings that had to fit with Lego bricks. And having the rings stuck was not an option. The rings had to be able to rotate, otherwise, I would just have canceled the project. :o I end up with this solution : The plates 2x2 with pin have a 1L liftarm (small DBG ring) that goes into the wheel and support it. There are 4 of these per wheel. Those parts are frictionless, so the x784 big rings rotate correctly. That was to support the rings. And to guide them even better, there are hinge tops (black) on the sides of the structure. Those parts make slightly less than an half plate thick, so it enables me to slightly reduce the width of the hole, and so to guide the rings correctly, still without friction. It was quite a challenge to design it, but I am glad it works. The setup is reliable and has very little friction. It tends to slip on a very slick surface of course, but works really good on anything else (wood, textile, paper, anything). If you are familiar with Technic sets, the build has much less friction than a Technic model with big tracks (42028, 42038 for example). The chassis is also interesting. With few studless and studful bricks, I got something very strong. The tile 2x2 with pins (dark bluish gray) locks the build. There is also some SNOT more or less everywhere. Technic parts to attach the missiles strongly. There are also some Technic parts to link the wheels to the arms. Here are all the components. The build can be considered as modular. A few more shots to see more details : UCS Hailfire Droid by Anio, sur Flickr   The proportions are accurate IMO, and the vehicle is well balanced : UCS Hailfire Droid by Anio, sur Flickr UCS Hailfire Droid by Anio, sur Flickr Here is the model in action : FlickR gallery : https://www.flickr.c...157656042536650 Brickshelf gallery : http://www.brickshel...ry.cgi?f=557811   Mathieu will create a professional instruction for this model when the instruction for the UCS Sith Infiltrator is complete. So, stay tuned ! :) I hope you enjoy reading this presentation. And if you have any question, feel free to ask. ;) Anio