Some people may think that, to create a MOC, one needs to have many parts, often hard-to-find ones. While this may be true for some of the great MOCs you see here on TBs , that doesn't necessarily mean you can't give wings to your imagination with only what's on the set you have recently purchased!
Just to give you an example, here are a few creations I found on Brickshelf. They are usually created from small or medium sets, perhaps because bigger sets are harder to have all (or at least the majority) of their parts reused on MOCs.
First and foremost here's a Jeep, made using parts from the 8256 Kart. DirkPV managed to create a new body shape while retaining the Kart's functionality (steering and piston engine), while at the same time adding working doors.
Next, there's a Truck Tractor, made by IcePicKPT using parts from the 8264 Hauler. Using all the set's wheels to make a rear double axis, as well as the attention dedicated to the front, makes this a quite realistic and serious-looking model.
Also, here's a MOC from mariner, who used the undercarriage from the 8294 Excavator and the rest of its pieces to build a Scissor Lift. One of the Linear Actuators lifts the "basket" to a considerable height, thanks to the number of straight beams this set contains. The ladder to reach the "basket" is a nice touch.
Again using parts from the 8294 Excavator, we have a Bulldozer created by Erik Leppen. In my personal opinion it is even better than the set's official B-model. There are even instructions on the respective Brickshelf folder!
Also, you might want to check out his One-Set MOCs folder for many other single-set creations of his.
From the 8292 Cherry Picker and inspired by a MOC by nico71, mrw created this Forklift. Notable is the fact that this MOC has four-wheel steering when the original set only has two-wheel steering. That's quite an achievement in ingenuity and improvisation.
Speaking of nico71, he created a great (not to mention proper; the official instructions only show how to built different attachments) alternative to the 8436 Truck, a Forest Tractor. Maybe the 8049 Forest Tractor with Crane will be something like this?
There are some other single-set MOCs at his folder worth checking out.
TECHNIC motorcycle sets don't usually offer much variation as to what B-model can be built using their parts, and the 8291 Dirt Bike is no exception. However, Co1Der managed to create something different with the parts, a Dragster. I especially liked the solution he came up with for the front wheels, where he used pulley wheels covered with Chain Links.
Due to their especially limited piece count and selection, entry-level sets offer quite a challenge for the imagination. That's why I admire grohl666's Monster Truck, built with parts from the 8290 Forklift. Not only the vehicle is quite different from the original, but also it has working suspension.
Like Erik Leppen, he has quite some more single-set MOCs (as well as other "regular" MOCs built with parts from multiple sets) on his folder, worth looking at. Among those is the one next on this article…
Finally, my personal favourite. This one is unlike anything I've ever seen, official set or MOC, and the fact that it was built using only parts from a single set, the 8294 Excavator, only gives it more value. Indeed, I've never seen a TECHNIC Parrot (or any other animal, for that matter) until I saw grohl666's Brickshelf folder. Not only it looks quite good, with Track Links covering empty areas on the body (another display of imagination), but it also has functionality: turning a knob on its back rotates its head, and via another knob on its butt (!) its wings flap. Truly brilliant!
I searched Brickshelf for quite a few sets, and these are what I found. It's interesting to see that the 8294 Excavator, last year's favourite set because of its versatility and selection of parts, was the one most used for single-set MOCs!
I'm pretty sure many of you TBs readers have also, on some occasion, bought some set, assembled its main model and perhaps the B-model, and then disassembled it and invented something with its parts. At least I have done it a few times in the past, only didn't document them. Want to share it with us? Then feel free to leave a comment with it!