This papercraft is the Blendin's Time Machine, based on the animated television series Gravity Falls, the paper model was created by RocketmanTan. Blendin's Time Machine is first seen in the episode "The Time Traveler's Pig."
The major plot line of the episode revolves around the time machine. The time machine is yellow in color with a greyish trim, and operates much in the same method as a tape measure. To operate the time machine, the user must pull out the tab to a desired point in time and press the button on the top. It will retract and the user will be send to the desired point in time. It is because of this feature that Mabel and Dipper are accidentally sent back to the pioneer time, when settlers were still moving through the Oregon Trail. It has been noted that the symbol on both the time machine, and in the book 3, seem to be representing a sand timer. The top half of it is shown above.
Gravity Falls is an American animated television series created by Alex Hirsch. The first episode aired as a preview on June 15, 2012 and the series officially debuted on June 29, 2012. The series is rated TV-Y7 and TV-G. [source: wiki]
The show concerns the adventures of 12 year-old twin brother and sister Dipper and Mabel Pines, whose summer plans are ruined when their parents send them off to their Great Uncle Stan in the fictional town of Gravity Falls, Oregon. "Grunkle" Stan lives in and runs The Mystery Shack, a tourist trap which overcharges unlucky visitors for a glimpse at the world's most bizarre museum, but little do Dipper and Mabel know that there really is something very strange going on and they must rely on one another to find their way in this unfamiliar town.
You can download the paper craft template here: Gravity Falls - Blendin's Time Machine Free Papercraft Download