Wednesday, June 23, 2010

Automatic Launching K'nex Ball Lift

This is a new K'nex lift mechanism of my own design. Rather than slowly lift a ball to the top of a tower, this lift launches balls up a small incline with a rubber band driven hammer. All the elements of this lift run off a single motor and 14 gears. The lift took about 5 hours to design, build and fine-tune and uses about 600 pieces. If I have the space and the time, I plan to integrate this lift into my upcoming large ball machine.

Here is a video of the lift in action
video


Overview of the entire machine


Note that half of the pegs have been removed from this gray gear.
This gear powers the red gear for 1/2 rotation (pulling back the hammer)
before disengaging it and letting the hammer swing back to hit the ball.

Thursday, June 10, 2010

Wednesday, June 9, 2010

K'nex Coaster Update 4 - almost there


I have started building the return track. I am still waiting on my 100+ feet of rail to come in the mail, so I have built this track by splicing together small lengths of track, which will later be replaced. The return track starts with a 4.5 foot climb up a hill, then down into a diving turn which sends it back in the right direction.

Because I am building outdoors, supports can be placed wherever I need them and then anchored in place by pounding k'nex rods into the ground. This eliminates the need for bulky bases and allows for strong tracks from very few pieces.


Another view of the diving turn.

Tuesday, June 8, 2010

Worlds Largest K'nex Loop: Test Launch 1 Successful!

video
I finished the runway and launch mechanism today and completed several dozen test runs with a 100% success rate! I was surprised at how little force is needed to launch the cars all the way through the loop, I built a 15 foot runway and it only takes about 3 feet of acceleration track to make it through. Here is a video both in real time and at 210 frames per second showing one of my test launches.

All that remains now is the return track. Construction will begin on that tomorrow.

K'nex Coaster Update 2


I have finally assembled the loop's structure after nearly a week of bad weather. I took advantage of a sunny day and built not only the entire structure, but the track as well. The loop is now 100% finished with a functioning and tested track, so all that remains to be done is the launch track (construction starting tomorrow) and the return track at the end. I am still waiting for about 100 feet of new roller coaster tubing to come in the mail, but I should be done within the next week.




Here is the completed loop structure supported by a gigantic A-frame, one of the largest, if not the largest structures I have ever built. The loop stands 12 feet tall and 12 feet wide. I have no idea how many pieces are in it, an estimate will come later.

Wednesday, June 2, 2010

K'nex coaster update




I have most of the superstructure completed, and it is now awaiting assembly in my yard. The two large half-circle pieces will soon be joined together to form the largest K'nex vertical loop ever built (to my knowledge). The loop will be 12 feet in diameter and will be the main attraction of the launched rollercoaster. The launch track will lead directly into the loop, followed hopefully by a return track consisting of a few small hills. The loop will be supported by the large frame on the bottom, and a 13 foot A-frame on the top. One of the legs of the A-frame can be seen in the grass on the left side. I hope to finish the structure tomorrow and start track assembly for testing by this weekend.

New Record-Breaking Roller Coaster Under Construction (Railgun 2?)

I have started construction of a new record breaking k'nex project. I will provide more information and photos once construction has progressed a bit further, but the design is a step up from that of Railgun. This will be another launched roller coaster, though for financial purposes I will most likely go for a traditional rubber band launch mechanism (rocket motors are very expensive.) The record I am attempting to break has, to my knowledge, never before been set (or even attempted.) The superstructure required to hold up this coaster is quite large, and will take quite some time to construct. I plan to finish the main element this weekend for some test runs, and the complete track within 2 to 3 weeks. Photos coming tomorrow.