Wood TrickWooden Marble Run Spiral Electric Motorized - Wooden 3D Puzzles for Adults and Kids to Build - 13x13 - Roller Coaster Mechanical Wooden Model Kits for Adults and Teens to Build

This was my second kit from Wood Trick. I assembled the Galaxy set a few months ago, and wanted to try this Spiral kit. I read reviews calling out "obvious design flaws" in the cam system that moves the stairs up and down. Cam shaft breaking, wire modifications to the lifting rods, etc. So, I paid maybe some more attention to that part of the kit. I smoothed the stairs, the connecting rods and the lower "forks" that ride on the cam wheels. Smoothed the cam wheels and waxed everything well. After assembly, I tried the cam set-up by hand. It turned and worked smooth and easy. When I completed assembly, there was no hint of a problem with the stairs.The problem I had, was with the outer return run from the trap, back to the pick-up deck. The ball was just coming down too fast and would often jump the last corner. I lightly sanded the top inside corners of the rails, to let the ball ride deeper between the rails and that slowed it down just enough to where it "almost" never jumps the track anymore.Running this kit for an hour or so, you may still find some places here and there that may need a little tweaking or smoothing, but right from the first start, it worked fine. All in all, I am very satisfied with the kit, impressed with the way everything fits together, and the clear instructions. (And I did not break a single piece while removing or assembling it).

Though this did need some powt-vukls tweaking, it was a nice build. Drive shaft needs to be VERY WELL WAXED. I snapped arm 2 before I noticed it caught. After that, I went back and rewaxed and it was fine! If you fit the pieces back the way they were with some glue, it works well enough.The pieces all were sturdy enough, but definitely take care on long, narrow parts. I did snap some of the outside marble track from pushing down on the middle of it, but that also glued back together smoothly. One actual design flaw that I might point out is that Some of the 90° turns on the marble track do allow the marbles to go off still sometimes. Could just be I need a little more tweaking or from the glued track 😅

This was a fun and challenging project for my wife and I. We enjoyed working together to put it together. I recommend you have a partner to check your work. There is a youtube.com video with detailed instructions. You'll need it because the static images in the book are often difficult to interpret. But the video clarifies thing. The reasons I only gave a 4 star rating is that when we were finished and started it up, the shaft on the eccentric cam shaft driving the ball elevator, broke and it was very expensive to have replaced. We had expected that Wood Trick would replace the defective items, but they don't. You pay for international shipping! Also Once everything is together and double checked, it requires a lot of tweaking to get it to work. Then because all connections are friction, the loosen with use. Then the balls start dropping and rolling on the floor, or flying off the rails, or getting hung up mid journey. I recommend once you get it running properly (not all that easy) you use spots of super glue to hold keep joints solid. Still, this is wood. it is not meant for continuous use. It's a novelty, not a running display. All of this said, we had a great time building it and were impressed with the creative design and engineering as well as the precision laser work.

This is my second WoodTtrick marble run puzzle/maze. Like my first the "roller coaster" it was challenging and fun to assemble. The use of a watchmaker's hammer definitely helped. Some of the parts are quite fragile and I broke a couple removing them from their respective sheets, fortunately spares were provided for the few i broke. After completing the maze a few days ago I am still tinkering with the arm to get it to pick up the steel balls. It seems as if this maze's operation is susceptible to "tweaking" when picking up and moving it that can disrupt it's smooth operation. However, overall very satisfied with the kit and quite frankly amazed with the design and engineering that goes into it. I highly recommend.

Way too hard there are several small pieces that broke, and we were dead in the water for days, We have done many 3D puzzles and are good at them and this is by far the worst. I don't know if it was specific to this puzzle or to the company, i did get my refund pretty fast, but upset that I wasted time on this and it was not really a good strong product.

Terrific hobby project. The mechanical engineering is great. This is my 3rd marble run and even though it cost the least it is my favorite. Looking forward to their next design.