Gravitrax Catapult
Print Profile(1)
Bill of Materials
Description
The Gravitrax element does exactly what its name suggests. The ball is launched through the air, and in my tests, regarding height and distance, it was very well reproducible. The catapult works with a standard household rubber band and, of course, heavily depends on it. The stronger the rubber band (depending on the chosen mounting positions for the band), the higher the momentum of the incoming ball must be to trigger the catapult. However, with the rubber band I used, I had no problems in any possible position, and the speed of the ball didn't even have to be very high.
To ensure the precise fit of the individual components, printing should be done at a layer height of 0.16mm (this applies especially to the small black element that is inserted into the larger one from below). They fit quite snugly so that nothing wobbles. Elephant's foot and similar issues will therefore likely require post-processing.
No glue is required, and everything fits quite loosely except for the vertical "stands," which is also necessary for its function.
Loading the catapult is done by simply pushing it down into the launch position. The latch for this is inserted from the front (marble entrance) through the first "arch" and can no longer simply fall out.
There are various stopper positions for the catapult that influence the distance and height of the ball's trajectory. The stoppers can also be changed in position even when the catapult is assembled (this worked very well with PETG, I haven't tried it with PLA).
No supports are necessary except for the small latch.
The following two videos help clarify how the catapult works.
The funnel shown in the video can be found here, and it worked very well for catching the balls. Another way to catch the ball, even on a higher level, is my horizontal funnel:
The balls can also be launched to higher levels and do not necessarily have to land back on the ground.
I printed it with Bambu Lab PETG HF because I have had very good experiences with this filament.
If you have ideas for further building elements, please write them in the comments, my children are happy about every new part.
I would be very happy about comments, experiences, and reviews of the print.
Otherwise, have fun with it!
If you are interested in more Skytrax accessories, you can find more in my collection.
License
You shall not share, sub-license, sell, rent, host, transfer, or distribute in any way the digital or 3D printed versions of this object, nor any other derivative work of this object in its digital or physical format (including - but not limited to - remixes of this object, and hosting on other digital platforms). The objects may not be used without permission in any way whatsoever in which you charge money, or collect fees.
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