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New K'NEX Coaster Design!
digimind
thwack
Yeah, I was tired of my K'NEX Screamin Serpent coaster taking up so much floor space in the living room, so I decided to relocate it to sit on / hang from the entertainment center. Check it out!



I also made a video that catches the action at every turn like olympic coverage of a bobsled run. :)

2MB MPEG

Originally I had shortened the lift hill so that it could sit and run entirely along the top of the entertainment center, but found that the short hill wasn't tall enough to provide the momentum to even get half way around the track.

So I rebuilt the full length of the lift hill according to the directions and added bars that stick out the side so that it can hang off the back of the entertainment center. Fortunately the clearance behind was JUST enough for the width of the hill. :)

The track itself is the same length as the original design, since I didn't want to cut or splice the purple part, which is just one piece for each entire rail. But I had to remove a little of the green supports since I unlooped the loop and that caused the length of green to be too much. (If that confuses you, try this experiment: Curve two Twizzlers into a parallel loop flat on a table. Now, holding the ends together, straighten out the loop. See the problem?) Fortunately the green part is assembled in short lengths so I could adjust its length.

Once I got the lift hill assembled and the track attached to it, I climbed up on the coffee table with the lift hill in one hand and the rest of the loose track in the other. I eased the lift hill into position between the back of the entertainment center and the wall, and dangled the rest of the track wherever.

Then I had to decide how to shape the rest of the track. Due to the fixed lengths of the purple parts, there were forced banked turns I had to deal with. In fact, much of the curvature of the track ended up being whatever the track wanted to do. I couldn't adjust it much without the purple ends not lining up or pieces of the green popping apart.

It ended up being a small first drop followed by a banked turn that plunges over the front edge of the entertainment center. From there I thought I should try to suspend the track from the front of the middle tower so it doesn't obstruct anything around the TV. I discovered that just over the top, there was a gap between two pieces of wood in which I could insert a K'NEX piece as an anchor. I then built off of that, forming a series of A-frames that wrap over the top, down, and around the bottom of the track. I built a matching frame and connected them together, holding up the track on one side of the center tower. Then I built another double-frame to hold up the other side.

An initial test run showed that the first drop barely provided enough momentum to get over the front ledge. Also, the spot where the track comes down to hang from the center tower needs to pass under an outcropping, and the track needs to be held away from it enough so that the train doesn't hit it. The suspended section in front was actually very sturdy, especially compard to what came next... the final turn around the left end of the entertainment center. It was completely lacking support, and flopped around wildly as the train went through.

Since I had plenty of K'NEX pieces left from the original supporting structure that was no more, I decided to build a custom structure that would sit on the CD tower and connect to the bottom of the lift hill. That provided sufficient sturdiness for that bend, and held the track away from the corner of the entertainment center as well, which was another concern.

Then I set out to build supports for the first drop and banked turn. I figured the train was losing momentum at the bottom of the first drop where the track was unsupported and could flex, so I built a support for that. I have the banked curve held up by a small section from the original structure that held up a bunny hill. But I still needed to hold the track away from the outcropping somehow. I built a little frame to hold a nearby section of track, and a long pole that stretches to the end of a section of molding on the entertainment center and hooks around it, pulling back on that section of track.

Voila!

All of that made it quite sturdy, but I found that it was also a bit loud. So I grabbed a bunch of packing peanuts and placed them between the lift hill supports and where they lean against the wall. (That should also help avoid scratching the wall.) I also placed some underneath the support at the bottom of the first drop and under the banked turn. Ah, nice quiet ride.

...except for that darn lift hill motor. Hey, anyone wanna build me a replacement K'NEX motor that is quiter and goes faster? :)

So anyway, I know it's kind of a roundabout way of saying it, but I guess the whole point I'm trying to make here is WE HAVE MORE FLOOR SPACE! That's all I'm really trying to say. And by the way, if someday you wake up and find yourself in an existential quandry, full of loathing and self-doubt and racked with the pain and isolation of your pitiful, meaningless existence, at least you can take a small bit of comfort in knowing that somewhere out there in this crazy old mixed up universe of ours, there's still a little place...

called Liiii-iiii, iiii-iiiive Journal!
Liiii-iiii, iiii-iiiive Journal!
LiveJournal! (livejournal)
LiveJournal! (livejournal)
LiveJournal! (livejournal)
LiveJournal! (livejournal)
I said L! (l)
I! (i)
V! (v)
E! (e)

...

JOURNAL! (journal)

livejournal-livejournal livejournal-livejournal
livejournal-livejournal livejournal-livejournal
livejournal-livejournal livejournal-livejournal
livejournal-livejournal livejournal-livejournal
LIIIIIIIIIIIII-IIIIIIII-IIII-IIIIIIIIIIIIIIIIIIIIIIIVE
JOURNAAAAAAAAAAAAAAALLLLLLLLLLLL!
[guitar solo]
[drum solo]
*BELCH*
[grandioso finale]

  • 1
I'll have whatever he's on, please!

Last I checked, it was going for around $90. :)

"All I have right now is this box of 1 dozen starving crazed weasles"

Oh, alright I'll take that.

  • 1
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