(My first Instructable!)
So, I kind of stole the idea for this from https://www.instructables.com/id/Book-Reading-Ring/
But anyway, I made my own design using Tinkercad. Added dragon wings and all that. Okay, so you can't really tell they're dragon wings, but that's not the point.
I got the 3D print of the ring from Shapeways... I don't have my own 3D printer. Yet.
Step 1: Tinkercad!
If you want to make this ring or a variation of it for yourself, you could take the shortcut and go to https://www.tinkercad.com/things/gZDm7RNowdu-readi... then print it, download it, or whatever; or you can keep reading and make it from scratch.
By the way- I'm assuming you're familiar with Tinkercad basics. If not, go through a couple of their tutorials first.
So. Start with a thin tube. Well, it's called "Tube thin" actually. Rotate it upright.
Then, stretch 2 boxes into a handle shape. Group them together. Duplicate the handle, and position one on each side of the Tube thin. Rotate as needed.
Step 2: Wings
This is probably the hardest part...
Take a Tube thin, and slice off the ends. (Meaning, group it with several holes.)
Duplicate it so you have a copy. Then rotate the copy and group it with the original so it forms an S shape.
Duplicate the S shape 5 times.
Rotate as needed as you fit the 5 S things into a single wing. Then group.
Trim off the ends if you want, then duplicate the wing.
Step 3: Top Thingy
Okay, I'll admit the top thingy is a bit useless, so you might want to skip this step. (I was planning on putting a page counter thing on the top, but meh.)
Just use 2 boxes as columns. Add a horizontal box, with a hole in it, to the top. Then rotate 3 smaller boxes so they fit on the Tube thin.
It's needlessly complicated, really. You should probably come up with your own idea or something. Although it does look nice when you're done.
Step 4: Put Together
First, take your Tube thin and group it with the handles if you haven't already. Make sure they're similarly rotated.
Add a wing on each side. To keep it symmetrical, flip the wings inside out. Meaning, if the wing is 20 cm wide, stretch it to "-20" cm wide. Then elevate the wings. Keep in mind how you want them to press pages down, and spin them around a bit.
Add the top thingy. Don't rotate it, just elevate it. Rotate the Tube thin if it doesn't fit.
Make adjustments, then group the whole thing together.
Step 5: Print!
Don't forget to resize the whole thing so it will fit on your finger!
Click "Download for 3D Printing" and choose an option. I think I used .stl, but you should choose depending on whether you want multicolor and stuff.
Then print with your 3D printer. I personally don't have a 3D printer (yet.) so I have no idea how that works. Or just order a print online. Shapeways worked fine for me; I did normal shipping and I got it in a couple weeks. You could probably get it faster if needed, but I wasn't really desperate to get my plastic ring.
I used Blue Strong & Flexible plastic and it turned out alright. Good detail. It's not really a shiny plastic, but I'm fine with that. It's pretty strong, too- I don't really want to see how far it will go, but it would probably be able to hold a thick 600 page book, if you're careful.