K'NEXThrill Rides – Electric Inferno Roller Coaster Building Set – 639 Pieces – For Ages 9+ Engineering Education Toy

This set literally took three hours to build by an adult. I thought it wouldn't take as long if I sorted out all of the pieces first. I think it did save time, but still, three hours is long. I enjoyed building it while listening to a television show, something I rarely get to do these days. The instructions could always be better. I find on the bigger sets there's room for confusion because there's so much you need to do and the pieces are little and somethings just bound to happen. I didn't make as many mistakes, and nothing that wasn't easily fixable. But just as I had it all ready to go I had to assemble the chain. I found this to be the most difficult part. You get more links than you need, and it's difficult to keep up with counting them. In any event, I think I had 107 links on there. It took a bit of adjusting to get the right tension and adjust parts so the chain wouldn't keep snagging. Once I had it all together and made a few changes it worked beautifully! And continues to delight our family. It's not really one of those toys you build and then take apart for a rainy day. It's a large set, so you need space for it. Fortunately we have a free spot where the Christmas tree would go, so we're really enjoying it along with a couple other large K'Nex coaster sets. Together they are all mesmerizing and the entire family loves them. Haven't had any issues. Except if you need to change the batteries you need to take the battery box off. The design of it doesn't allow you to simply remove the batteries and add new ones. That's the only issue.

Got this when it was a Deal for my kids. Bought this instead of another set (the "Web Weaver") which used a rechargeable car on the track using a lithium battery which requires charging.Ended up spending Christmas afternoon setting it up. One piece was missing, but it was not a show stopper. The rods and connectors are positioned so that the track follows the path shown in the picture with only a few excess parts.The motor driven chain pulls the car up to the highest point on the track, releases it and the car then travels around the loop and reattaches to the chain at the base of the tower. This takes about a second or two.Now, the chain has some play and this may cause parts of it to run on the edges of the chain guide. When this happens the car get stuck and it could result in the chain snapping/breaking. If this happens, you'll have to re-thread it and snap the links together. This gets tiresome after a while.Chain slippage may also be cause by the surface on which the tower rests not being vertical or parts not firmly put together. The upper and lower sprockets should be in line to have the chain travel correctly. Tightening the chain by removing links caused it to break.In addition, as the chain guides cannot swivel where they are fixed on the track. At the apex of the tower, this may result in the car getting stuck and the chain snapping. Re-positioning the chain guides and the supports,helped to getting it work more reliably.Perhaps these problems with the chain and guides were caused by the missing part which was part of the track support close to the apex of the tower.In any case, it was a great set at the price, but perhaps I should have got the "Web Weaver"...

This was a super fun project to build with my daughter! It took a couple days but, worth it! There is one area that pictured 3 wide washer beads when it really only needed 2. We thought we dropped it and the dog ate it so we went on a manhunt for alternatives around the house and found 4 washers only to realize it was a misprint. We used 3 less pieces of the black cart track used as the machenism to make it pull up to the top of the coaster. Still, loads of fun and beats an iPad any day of the week!!! Piece unnecessary is marked with an X on page 21 in picture.

My grandson had this pit together in a few hours. He thought it was a great gift. Would recommed this to a teen who is intersted in building, engineering and physics

This thing is awesome but there is going to be some tweaking. Make sure you start by doing a count of all the pieces. We were missing 2 pieces but I have a six year old that dumped all the stuff into a pile so maybe that's on us. Kinex responded right away and sent out the pieces once we emailed then.It's good to separate all the pieces into groups and put then into Ziploc bags. Helps so much. Other than that, it's was good for my six yr old to follow directions and works in steps. We used it as a father son project and he loved it.As far as the tweaking we didn't use one link and disconnected a top support. Seems to make the chain run smoother and more reliably.

I thought that this knex was not as sturdy as some of the others my son built. it was kind of leaning a little too much that is what my son said. but other that that it a fun project and a great build. it is also very cool looking and my son said that he was impressed by it besides the leaning problem.

We got this for our 8 year old daughter for Christmas, and she loved it (as did her 6 year old sister). I built most of it because she was tired after having built the Ferris wheel set, but she was able to help. Upon taking it down to pack it for the return trip home, she broke two connector pieces. Thanks to the tip of another parent, I learned that K'Nex will replace broken pieces! I ordered the replacements online in about three minutes, and it was done. So, not only was the product fun for the kids, it was a relief knowing that if we need parts in the future, it is a simple process.

So disappointed. I bought this for my son for Christmas. He spent over an hour putting it together just to find out the car just gets stuck every other curve/flip. Not worth the money, I'm returning it.

We bought it for our grandson’s birthday and he loves it. It took several hours along with his father’s help to put it all together

Llego en perfectas condiciones, y es muy divertida . . . . . . . . . . . .

Parfait pour un enfant de 12 ans. Pas facile à faire et fonctionne bien. Des heures de plaisir.

My grandson loves it! I very much appreciated the speedy shipping as well!

Purchased for 7 and 5 yr old brothers, very cool. Does, at their ages, require parent help but fun for them as well!