A couple of Lego Power Miners sets my kids got had some structural pieces that looked like crane parts. So, when they dismantled those sets and we started building a Lego city, a construction site with a crane was naturally on the to-build list!
The crane pieces were so obviously crane pieces that I figured I'd save myself some design time by looking up the instructions on Lego.com or google for pictures of how others had built cranes out of these Power Miners pieces. Strangely, I didn't find anything. So -- since the crane I designed worked out pretty well -- I thought I'd do a quick explanation of how to make one.
Start with the stem of the crane. For stability, rods should hold the pieces together wherever possible (though sometimes it's not possible, such as when adding the turntable to allow the crane top to rotate). A round piece should be included below the platform (and connected with a rod) for added stability.
The crane arm also needs to be reinforced with support rods, and -- naturally -- also needs angle pieces to attach it to the base and to the part that extends above the base.
Then there's the cable mechanism, which starts from the weight/reel on the short end of the crane arm, goes through the loop at the top of the crane stem, and is directed by a moveable attachment that goes around the long end of the crane arm. Here, I've taken the little ball off the end of the reel axel so that you can see how the reel fits together.
The last bit is the crane operator's cabin. There's a lot of leeway in precisely how to design it (depending on the pieces you have). The only important part is to include a piece with two holes near the top so you can connect it to the top of the crane stem:
Then, all that's left is to put the components together!
Now, at this point, probably a lot of people are asking: "Are you doing this for yourself, or for your kids?"
Answer: both. I think that -- in order to spend quality time with your kids -- it helps to take a sincere interest in the things they're interested in, and talk with them about things they care about. And these kids love Legos!!! Here they are taking publicity photos for their own invented Bionicle sets:
I wanted to make a city for the kids to play with so that they'd see what you can really do with Legos when you get a certain number of them. And Leo absolutely got into it -- here's the city he made, inspired by the one I made:
Legos were some of my very favorite toys as a kid, so it's easy to get excited about what they're up to! Here are a few more vehicles I made for Leo this morning: