A friend of mine is a geometry teacher who loves nature. So for this holiday season, I thought of making her some earrings where I mix the two things that are very prominent in her life.

Alright! Without further adieu, let's get this ball rolling! :D

Supplies

So for this tutorial, you will need the following:

A TinkerCAD account
A slicing program (I am going to use Chitubox)
a thumb drive
3d Resin printer (I have an Elegoo Mars 2 Pro)
water washable resin (I used black from Elegoo)
paper towels
A pickle jar with a basket inside filled with water (I got mine off Amazon for like 8 bucks)
A UV light and a UV turntable
a funnel
some form of strainer for the funnel (I have one that came with my funnel that is metal and reusable)
A small cardboard box lined with aluminum foil
two scrapers: one metal with a fine edge. One plastic without a harsh edge
Rubber/latex gloves
A set of needle nose pliers
Two earring hooks
Jump rings: 2 medium size, 2 small size
Feather charms (I got these in a strand from Joann Fabrics)

One optional item:

an arm adapter for your 3d printer that will allow excess resin drip off after printing. My printer came with on, but I don't know if all do, so its optional.

Step 1: Creating the Design for the Back Piece

*** This step is very detailed. If you are familiar with TinkerCAD, you could probably use the images to recreate it, but if you are not familiar, I hope the details help. ***

The images I have added to this step follow along with the steps below to help visually.

If you don't have a TinkerCAD account, it is free to sign up and it is very user friendly. I am going to go through the steps of how I made the design for the back of these earrings.
Once you are signed into TinkerCAD, you will see a "Create" button. Go ahead and hit that and select "3d Design" and it will bring you into a new file.
On the right hand side, you will see a bunch of shapes. We are going to create a box, which is the red box. To do that, click the red box icon and drag it into the workplane. The workplane is the main area with the light blue grid.
If the box isn't already selected, you can click on the box and an info box will pop up next to the shapes where you can change the perimeters. We are going to set the length and width to 9 and the height to 1.
Next, with the flatter box we just created still selected, you are going to click the "Copy" button right under the TinkerCAD logo in the upper left corner. Once you click that, without clicking anything else, click the "Paste" button right next to the "Copy" button you just clicked. This will create a duplicate of your box just to the right of it.
With the new box selected, in the info box with the perimeters, you can now change the length and width to 7 and the height to anything over 1, I am going to choose 3. Also, we are going to change this box to a "Hole". Above the perimeter sliders, you can see where you can choose "Solid" or "Hole", click on "Hole" to make this happen. You will see the box change from red to a see through gray.
Next, we are going to select both boxes and align them. To select them, you can click anywhere around them and drag to create a selection box. If you drag the selection box to go over both boxes and let go, it will select them both. With both selected, we are going to click the "Align" tool that is above the info box. Once you click it, it will put new tool manipulators on the boxes. They will appear as black dots, 3 on each axis. We are going to want to click on the middle black dot of the length and the black dot on the height, as seen in the images here. They will be orange when you hover your mouse over them and will turn gray once you click them. The centers of both boxes should now be aligned so it looks like the hole one is cutting through the center of the red box.
Next we are going to group the boxes. When you group a solid and a hole object, it will cut the hole object out of the solid. To do this, with both boxes still selected, click the "Group" button that is over a couple buttons from the "Align" button we just used. Once it is done, you will see the box now has a hole in it. We now have one full piece of the two pieces we need to make this.
Now we want repeat the steps in Step 5 to create a second object like the one we created.
After that, we are going to move the copy by clicking and dragging on it until the two corners meet up. There will be two position indicator boxes that will update everytime you move it. You will want it to say 8.00 in one and 3.5 in the other. You may need to click in the one that isn't 8.00 and change it to 3.5. In the images you will see that just by dragging it, I could only get 3.75, but you are able to manually enter just by clicking in the indicator box. You just want to make sure the two corners are overlapping perfectly.
The last step is to select both boxes again by clicking and dragging over them like we did in first part of Step 7 before aligning. Once you have them both selected, we are going to repeat Step 8. When you group two solids together, it combines them into one object.

Now we are ready to get this out of TinkerCAD and into the next program to set up for printing.

Step 2: Getting Our File Ready to Print

In this step we are going to take your TinkerCAD file out of TinkerCAD and start working with it in Chitubox to get it ready to send to the 3d printer.

While still in TinkerCAD, you can hit the "Export" button in the upper right corner right above the Shapes. When you hit this, you will get a dialog box that will ask if you want to do everything in the design or what you have selected. If you have the object selected, you could choose either. Then under "For 3d Print" select .OBJ.
When TinkerCAD has finished exporting your file, you will be able to find it in your Downloads folder on your computer. It will be in a zip file, so open that up to extract the files. Extract them to any place you find convenient for yourself. I am going to keep them in my Downloads folder for the purpose of this tutorial.
Once you have it unzipped to the location of your choosing, let's move on to Chitubox. If you have not downloaded the program yet to your computer, you can find it at https://www.chitubox.com/en/page/chitubox-free We will be using the free Basic version. It is pretty easy to use, but I will be going over it with you.
To download it, follow the link above and hit the blue "Download" button. It will prompt you to choose what OS you are running. Choose which one you are using and then click the blue button below it to download.
In your Downloads folder on your computer, it will show up once it is done downloading. You will find either an .exe or a .dmg depending on which OS you have. Follow the installation instructions and once you have it installed, you can find it on your computer by performing a simple search for "Chitubox" in your search bar (Windows) or in your quick search (Mac).
Let's open up the new program and get started. Once you have it open, you may have a pop up asking you if you want to automatically get updates, you can either accept it or not. I am going to click it off and close it.
In the upper left corner, you will see the "Open" button. Let's click on that and navigate to our .obj we exported from TinkerCAD.
Once you open it up, you will see it shows up on the grid. On the right hand side, you will see the name of the obj and that it is selected by the color around the name. Since it is selected, you can now copy it because we want two of these printed to make the pair of earrings. The "Copy" button is on the top bar 5 buttons over from the "Open". It looks like a piece of paper with a second one behind it. When you click on it, a second obj will show up. The nice thing about Chitubox is that it will automatically copy something so its not overlapping with your previous one.
Now we are ready to set up the settings for our printer. I recommend the settings in the images. I have used these for smaller objects a lot without much failure. The only ones you will need to change are the "Print" and "Advanced" tabs in the Settings.
Some people may cringe at this, but I am keeping these flat on the build plate since they are flat. Some models I recommend rotating them and adding supports, but for the purpose of this model, there is no need.
To get this out of Chitubox and ready for your printer, hit the gigantor "Slice" button.
You will see some details regarding the Chitubox slice file on the top. Make sure to pay attention to the "Volume (ml)" number. This shows you how much of the resin you will need to finish this print. Since this is a very small object, it isn't much at all.
Make sure you have your thumb drive plugged in to your computer and go ahead and hit "Save". Navigate to your thumb drive and save it. Make sure to choose the ".ctb" extension for it when you save.

Now we are ready to zoom on over to the 3d printer and get it ready for the magic... and the waiting... oh the waiting.

Step 3: Printing Your Pieces

NOTE! A lot of newer 3d printers are now becoming wireless. I am very excited to get that and if you have that ability, you could just wirelessly send your file over, but for the less fortunate of us... like me, thumb drives are our friends.

First thing you need to do is boot up your printer. With mine, I need to do this before inserting the thumb drive. If I do before booting it up, it won't be able to read it. To boot up your printer, there should be a hard switch. Mine is on the back and when I flip it on, you can hear the printer start up and the LCD screen will light up as well.
Once you have it completely booted up, go ahead and eject your thumb drive from your computer and plug it up to the USB port on your printer.
Before moving on to the printing, we want to make sure we get the resin in the vat. For this step, please! put your gloves on. Take your little graduated cup and your resin. Measure out how much you needed based on what Chitubox box said when you saved out your file in the "Volume". I always like to add a little more because I like to be safe than sorry. I don't know how many times I had prints fail when I started out printing because I under estimated the resin.
Go ahead and take the cover off your printer and pour your measured resin into the vat.
Once you have that in, you can put the cover back over it and we can start printing.
On the Mars 2 Pro, the LCD screen will have three buttons, choose the "Print" button. In here, it will bring up the directory of your thumb drive. Select the file you are printing. OBSERVATION! Make sure it shows an image of the obj, if it doesn't that means it will not be a recognizable file and you will need to go back to Chitubox with your thumb drive and resave it. It happened to me, but it was because my thumb drive was formatted for a Windows rather than a Mac, so make sure your thumb drive is formatted correctly and that may fix the issue.
Once you find your file, select it, then hit the "Play" button. Once the build plate reaches the bottom and it starts the first layer, it will show you on the bottom how much time you have. This one is pretty fast since it is a small print and we are only going to have to wait 10 minutes. The more layers you have, the longer it will take.

Step 4: Cleaning Up Your Print

This step we will be cleaning up our print for the final piece. Oh so close to finally have finished earrings!

This step of this step is optional. Once it is done printing, I like to take the arm adapter that came with my printer and hang the build plate on the arm for an hour or so to let any excess resin drip down into the vat. If you don't have one, you can still let it set in your printer and let is drip for a while before moving forward. Remember to put the cover back over it as it drips to prevent any UV's getting in. You can also turn off your printer at this time.
After it has dripped to your liking, you can take the cover off and take your build plate off.
Get your gloves back on and get your metal scraper. We are going to use this to scrap the pieces off the build plate.
Lay a paper towel down on your table and put your build plate on it. With gloved hands, take your scraper and lightly pry the pieces of the build plate. If they aren't budging, you can run hot water over the build plate for a bit and that will assist with getting them to pry off safely. Mine popped off pretty easily.
Next, get your "wash", which is our pickle container with the basket that is filled with water.
Drop them in and lift the basket up and plunge it back down over and over for about 3 minutes to wash the pieces.
Once you have them washed, dry them off with a paper towel and put them on the turn table with the UV light facing it. Turn it on and put the aluminum foil lined box over top. Let me cure for about 30-40 minutes. After that time, if you come back and they still feel gummy to the touch, cure them for longer. You don't want a gummy feel to them. Once you don't feel that, they are cured and you can wipe them with a paper towel.
Last thing is go ahead and turn your UV light off, you are done with it. :)

And on that note, get ready to assemble your earrings!

Step 5: Assembling Your Earrings

Now for the fun! Not saying the last steps weren't fun, but cmon, this is what you came here for!

Gather your supplies. You should have your pieces you just finished, the earrings hooks, the 4 jump rings (2 medium, 2 small), and the two feather charms.
Grab your needle nose pliers. If the jump rings aren't open already, just lightly pry them open with your plier and your fingers. if you don't have the dexterity to use your fingers, a second plier would work just as well.
Take one of the earring hooks and loop a small jump ring through the end of the earring. Close it up with the pliers, reverse of how you opened them. Make sure the two ends are nice and snug together so the earring hook won't escape.
Next grab one of the medium jump rings and loop that through the small one.
Next go ahead and grab one of your printed pieces and loop that on to the jump ring. I find holding this all with a pliers makes it east to just look it on.
Finally grab the feather charm and loop that on. You want to make sure that when you have it all assembled that the feather will be facing forward and in front of the 3d printed pieces.
Once you have them on the jump ring, go ahead and close up that jump ring like you did the first. Again, make sure the ends of the ring are snug so nothing can fall off your earring.
Now you should have a finished earring! If the pieces are in the wrong order when its done, you can easily open the medium jump ring back open and reserve them and reclose it. Easy Peasy.
Repeat these steps to finish up the other earring and VIOLA! You have some super cute earrings.

Step 6: OPTIONAL! Cleaning Up Your Mess

This step is optional, but it is all about cleaning up your printer and making sure things are put away. Please excuse my lack of descriptive photos on this step. I had to use one hand and really it is a two hand job to clean it, so some of the images aren't very telling on what I am doing.

Your build plate should still be on the paper towel, with gloved hands again, you can take a second paper towel and wipe all the excess resin off it and put it back on the arm of the 3d printer once all the surfaces are wiped off. This includes the sides of the build plate as well as the top.
Once you have that in place, go ahead also wipe off your metal scraper and put that away.
Next, put the top back on the pickle container and put that away and also double check you turned your UV light off.
Now, grab your resin bottle and the metal funnel with the strainer. Put it in the top of the bottle and go ahead and loosen your vat on your printer.
Take it out as to not spill any resin. With the corner that has the round divet in it pointing down to the funnel, go ahead and pour the excess resin through the strainer back into the bottle. The strainer will help get any solids that may have come from the print out of the good resin and keep it out of your bottle.
Next take your plastic dull scraper and scrap LIGHTLY any other resin you can get out into the funnel. I say lightly with emphasis because if you press on the film it can damage it and also potentially puncture it. Just get as much out as you.
Once you have enough out as you can get, set the bottle with the funnel aside to let it finish straining while you finish cleaning.
Set your vat on a new clean paper towel. Then take one of the ones you already used and wipe all the other excess out. Make sure nothing is under it that can press up on the film and also don't scrape the paper towel over the film too hard. Just get as much out of the corners and along the sides as you can. Also wipe down the metal part also. Once you are done, you should be able to put it up to the light and see its relatively clean.
You can also do this again with a wet paper towel to get more of it out if you want then dry it with yet another, but I find just doing the one go is efficient. I have been using the same vat and cleaning it this way after each use for about a year and its still going good.
If your vat is clean to your liking, go ahead and put it back in the printer, fasten it back in place and put the top back on your printer. You are now done cleaning that and it is ready for your next print job.
Next take your plastic scraper and wipe that clean and put that away with your other scraper from earlier.
Lastly, let's clean our funnel and strainer. You can either continue to use the paper towels you've been using, or you can grab a new one.
Take the strainer out and wipe it clean on all surfaces, under and over. Go ahead and put it away.
Take the funnel and string the paper towel through the stem of it and twist a couple times, then pull it all the way through. Then wipe down all the other parts of to make sure there is no resin. Once it's clean to your liking, put that away and you are done.
Dispose of your gloves and all the used paper towels responsibly.