For my 3D printed impossible object, I wanted to do an articulated animal. I searched the files on Thingiverse and came across a hammerhead shark I really liked.

I started by printing the shark with the Bambu FDM printer at three different scales at 20, 30, and 50%. The shark had supports to help with the vertical tail and keep the parts stable while printing. The two smaller sharks printed well but only the ends of their tails articulated. The 50% shark had a little more movement but the fins did not fully print. I tried again at a larger scale, but I discovered that to get the shark to fully articulate, it would need to be way bigger than the capsule.

Since the shark was not to fully move at a smaller scale, I decided to switch to printing a lizard which had more flexible joints. 

I printed the lizard at 30 and 40% scale and without supports. With the Bambu printer, the lizard printed very well except for two of its feet. I tested it in the gumball capsule and it had plenty of room. 

I scaled the lizard up to 70% and it printed perfectly. All of the feet printed and the lizard is fully flexible.

For my other printing method, I tried printing the lizard with the SLA resin printer. This was my first time using this type of printer and it was cool to see how the printer made each layer. I used the clear resin and it turned out really nicely. After the first step, I noticed the joints could not move and the lizard would not be able to fit inside the capsule unless I made it really small. I continued with the washing and oven steps to finish the resin, but I knew I would have to pick a different printing method.

I then printed two more lizards on the Mark4 Prusa Printer. These prints turned out well and look exactly the same as the prints from the Bambu. As a result, I was able to create 5 identical lizards that fit inside the gumball capsules.

Cost Analysis

Cost Type	Item	Cost	Source	Quantity	Total
Material	PLA Filament	$16.99	Amazon	1kg	$16.99
	Clear Resin	$79	FormLabs	1L	$79
Labor	3D Printer Worker	$23.09/hr	ZipRecruiter	1 hour	$23.09
	Prototyping Engineer	Custom	Self	1 hour	–
Total Cost					$119.08

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