Hi

 

I would like to talk about my description of my project by saying that I thoroughly enjoyed this project because I found it most relevant to the research I was conducting and found it easier to balance my schedule with this project.

 

In this project, I created a gyroscope ring toy, as seen below, for my impossible object.  I used an FDM Prusa 3-D printer and an SLA stereolithography 3-D printer using ABS-resin. Specifically, I used a 3-D Prusa printer; however, because I wanted my skills to translate well to the skills I needed for research, I decided to use the SLA 3-D printer in my lab called an Eleego Mars Pro printer. Both the Form Labs and Eleego Mars printers are SLA printers, and while I understand that Form Labs is considered the nicer, I figured I should learn to use the Eleego Mars printer because it was most relevant to my research skills. 

 

The original dimensions for the following print was 550 mm x 50 mm x 20 m. I scaled this by 50% on all dimensions, 25 mm x 25 mm x 10 mm, to fit the gumball holder. However, I didn’t realize this size would fit all five of my prints in one gumball holder. 

 

The first print I made was with the Prusa. The infill would mess with how easily my prints would turn out or how easily for a low in-fill of 30%. I also saw that the higher the in-fill, the higher the print time, so I decided to use a low-infill for that reason as well. 

 

The first print I made turned out nice; however, when I needed it to post-process, it took quite a bit to achieve some form of mobility. The top of the print was loose and mobile, but the base, due to supports, needed to be sanded quite a bit until I could scratch off the connections. I used 300-grit sandpaper to sand down the supports, and I even used a scaffold blade in my lab to cut or separate the circles from each other.  It should be noted that I used the Prusa software to do all this. 

 

The sanding worked to produce the mobility with the print. However, I did not like how it looked with all the edges uneven as it was clear the post-processing happened. I tried creating a different piece, and I made a second piece that turned out fantastic. And I did not even have to do any post-processing to produce mobility. I still sanded them to avoid any remnants of the base, but I used a small grit.

One issue I encountered was that I decided to print all 4 pieces at once on my lab’s prusa. I decided to return after a couple of hours, and everything was gone as a clump of PLA surrounded the entire nozzle. I had to start the Prusa again and scrape any PLA off when the nozzle heated it. 

I found working with the SLA Lego Mars printer easier and harder at the same time. I found using the SLA printer much faster than using the Prusa printer and much easier to print multiple at a time. However, I also learned the importance of using support when printing with SLA printers. 

 

The first print, without support, printed nicely, but when I had to take it out, I had to scrape it off and use excessive force that damaged the print, as seen below. Furthermore, the exposure time needed to be higher as cracks were present in the print. For the next print, I doubled the exposure time and more closely aligned it with the resin I used.  

Since the print was directly on the metal holder, I used supports to take off the print more easily, as seen below. To be safe and ensure that the print could be as good as possible, I put as many supports as possible to easily twist my print. 

Overall, my SLA prints turned out nicely. I decided to post-process them by rinsing them in isopropyl alcohol(IPA) for 20 minutes and curing them for an 30 min in a UV system. This reduced the resin feel surrounding them. 

Next time, I would use the FormLabs printer, which is much better. I would also like to sand my SLA resin pieces since they have the following pattern on the back. I sanded the SLA and FDM samples but I feel that I could have done more to make them smoother or used  more consistent and uniform sanding. 

Cost Type	Cost	Price	Source	Quantity	Total
Materials	Resin	$39.99/kg	Amazon	30 g	$1.2
	Grey PLA Filament	$18.99/Kg	Amazon	60 g	$1.14
Labor	3-D printing technician	$21/hr	ZipRecruiter	4 hours	$84
	Project engineer	$38/hour	Salary.com	4 hours	$152
Overhead	Prusa -SLA printer	$0.21.hour	blog.prusa.com	5 hours	$1.05
	Eleego AMRs pro-SLA printer	$330	Toms hardware critic	~	$330
Design	Design Engineer	$38.55	Indeed	1.5 hour	$57.83
Total					$628.22