ROKR3D Puzzles for Adults-Wooden Marble Run Chocolate Factory, Brain Teaser Model Building Kits for Adults to Build, Desk Decor for Boys Ages 14+

Great for Adult. Super Fun.

It's a ROKR model so you know it will be well designed and executed. The pieces are cut to very close tolerances and mesh perfectly. They are easily separated from the sheets so you won't wind up with bruised fingers and most pieces are individually identified so if they are separated from the sheet unintentionally they can be identified. The instruction manual is very well done (as with all ROKR kits) and, as an added benefit (at no extra cost!) the manual includes word puzzles where you can attempt to decipher the English translations. If you're a veteran marble run builder, this is not the traditional marble run you're accustomed to as most of the pieces are decorative, rather than functional, and the actual run is minimal. I found the mechanism to raise the marbles unique, clever, and unexpected! Great fun to build!

What can i say!!! I love this one! It is time consuming and some of the parts are very fragile..keep glue by you. But I loved putting it together! Pieces fit where they were supposed to. Directions were clear to read. However alittle misleadleading with the stick to make the gears to go smoothly the pictures says grey area which there is not a gray area. But so much fun. And the end is pretty my kids love it! As everyone I shared the video with. Recommend getting this if you need that time to decompress. But beware you will not be able to stop until you are done.

TLDR: Read instructions and test often. Definitely recommend!The full review:Great build that took around 30 hours to complete. Very decorative and cute. Anyone who builds kits by ROKR/Rolife knows the need to pay very close attention to every single step to ensure correct assembly. Also, for marble runs, it's important to continue testing the functionality throughout the build. The worst is when you build the whole thing assuming you did everything right, only to find it doesn't work at the end. Recommended for anyone who wants a challenging, yet fun project!

Like many other reviews on here, be prepared to buy lithium batteries because this kit doesn't come with it automatically.Putting this together was a challenge - but a really fun one! But in the end, I was slightly disappointed because no matter how careful I was, and no matter how much wax i used on the gears, it didn't work. Still though, it's a very impressive and pretty display piece!

To my surprise, it worked. I had my doubts while building it because the wooden gears kept sticking. The one weak spot is with the gear at the end of the crank handle, it doesn't mesh properly with the next gear in the train. Spacing it further down it's shaft and epoxying it in place solved the problem. This is not for kids, the assembly isn't that difficult, just time consuming and at times frustrating, and you will have to work out difficulties as you go. Still, it is impressive once built.

My eleven year old got this for Christmas and between the two of us we had it done between Christmas and New Year's day. It is absolutely adorable, with a lot of sweet little 'hidden' details, and he is so proud of himself. The only complaint is that we constantly worked the gears each step of the way to ensure they were going smoothly and almost as soon as we installed the last portion that enclosed them and made them inaccessible, something went wrong and now instead of the beautiful smoothness, it's choppy and difficult, so he and my husband are going to try and figure out a way to get it apart enough to find the problem. Such a shame because it really does work beautifully.