Hello hello!

For my 3D printing project, I immediately decided I wanted to make chains. During class when we were learning about 3D printing techniques, I saw various types of chains and was immediately enamored by then so I had to try to make some myself!

I found a nice and simple 5-link chain from thingiverse. A picture of the .stl file can be seen below: I decided to use chain as my impossible object, as the only way to make this exact piece out of one constant material with no any gaps is 3D printing. Another manufacturing technique for chaain link could include cutting bars, bending them, and welding the ends together, but that would utilize multiple small pieces, rather than one continuous piece of stock material.

 

FDM Printing!!!

I then imported this file into 3Dprinteros to prepare the file to print it on the 3D printers on the maker bar wall at the OEDK, which included both the Prusas and the Ultimakers. Here is the initial size of the model: I sliced this file so that I could print it on the Prusas since more of those were available to use when I was doing the work at the OEDK. Here is the preview of the file I was printing initially:Soon after I started this print, I realized that this detached skirt was not sufficient to help the chain attach to the Prusas’ bed, as the piece quickly didn’t stick to the bed, causing the print to fail. I then went to add a full raft to the base of the print to help with bed adhesion. However, there is some bug in 3Dprinteros’s slicer that causes it to believe that a raft will take 50+ hours to print. Additionally, the OEDK prevents you from printing something that will take greater than 24 hours, so I wasn’t able to attempt this print. Here is a screenshot from that:Without the ability to easily print this model on the Prusas, I decided to switch gears and attempt to make a Quad Cube since it wouldn’t have as many issues with bed adhesion. Here is that model’s layout and sliced file preview:I went to print this file and was right – it stuck to the bed very well! However, the insides components of it did not work correctly without any supports.

After this frustration, I left the OEDK for the day to return to other assignments for other classes, only to be informed that I had to quarantine for the next two weeks. So fast forward two weeks + Thanksgiving, and it was now time to return to this project!

Still set on making chains, I returned to that thingiverse file. I decided to make the chain bigger, hoping that would help with bed adhesion, realizing that a much bigger chain could fit in our gum-ball containers.  Here is the resized chain:

Using this resized chain, I again printed it on one of the Prusas with the following path preview with a brim this time, as the raft feature was still not working:

For the first ~half of the print, it was working flawlessly! By the end, a few of the chains had shifted a little bit however, resulting in the following print failure where the tops of some the chains are shifted or non-existent:  But hey I am making some progress and have the beginning of a physical chain 🙂

With this half-success, I began printing some more on the prusas with less luck. Here are some more failures of mine:  After numerous failures, one of the Ultimakers became available! I then created new gcode (seen below) and began printing on the Ultimaker which much greater success! The second preview is the gcode using the second extruder of the ultimaker depending on what filament was available.

Here is one of my prints in progress on the Ultimaker!

And here are four of my chains, all printed from the Ultimakers. Do to the availability of filament, the two tannish-yellow colored chains were printed out of PVA (using the second extruder on the ultimakers), while the grey and white chains were made out of PLA (using the first extruder on the ultimakers). So voila! We have four chains made using the FDM printing method on the Ultimakers!!!

Now on to the SLA printed chain. After hearing that the formlabs were out of commission for the rest of the semester, I received news that they were alive again so I was able to use those to print another set of chains using SLA.

I began by downloading my scaled .stl file from 3Dprinteros, to ensure that the different chains were all the same size. I then uploaded that into the Pre-Form software on the Formlab 2’s computer. I set up the orientation, supports, and layout automatically using the Formlab’s preferred settings. Here are some screenshots of the build path preview:After it finished printing on the Formlab, I removed the build plate.

Put it in the curing bath for 15 minutes (the time specified for the specific grey resin used).

Then I was able to take my chain off the build plate and remove the supports. I then realized that the individual chain links were actually fused together with spare resin. I tried breaking the chains apart with no luck.

I then re-made the file and started the print on the Formlab 3. After attempting to print a few more times on both the Formlab 2 and 3, I kept receiving this error on both machines

Unwilling to try to fix these expensive machines without any other lab assistant or a lab technician at the OEDK, I called it a day.

I was able to learn a lot about how to use the machines and the parts post-processing steps. However, I have yet to make a successful chain with them – hopefully in the next couple days if I have time and there are people at the OEDK to help me.

So there we have it! Four amazing “impossible” chains 3D printed with FDM technique! And a lot of knowledge gained on how SLA printing works.