What do you get when you throw together the Amazing Gyroscopic Cube Gears and the Fantastical Heart gears and throw in a bunch of hearts for good measure???
You get the ultimate 3D printed mechanical Valentine of course!!
After designing the Fantastical Heart Gears for my wife last Valentines Day, I wanted to create something even more wild for her this year.
I took inspiration from my earlier creations and thought it would be awesome if I could have the heart suspended on an arrow and rotating.
Well, it all came together quite nicely.
Here's a video of it:
My 8 year old daughter helped with the video to demonstrate how easy it is to turn. She kept stopping and starting to try to stop it at a point where the heart was reformed. As it rotates, the heart is reformed at a different angle than the last time. I need to count it to confirm, but I believe that it has to go through 12 cycles at about 3 rotations a cycle to bring the heart back around to the original starting point.
Update - by request, I modified the heart pieces to thicken up the places where the walls were too thin. These new parts have "Thicker" at the beginning of their names.
All pieces are snap-fit. No glue or screws are needed. For this to work well, everything needs to be able to spin freely. That is accomplished via a combination of well-fitting parts and proper lubrication. Make sure that each part fits and turns without catching. If they print well, there should be little to no cleanup needed for that. For lubrication, I use CRC Heavy Duty Silicone lubricant. It works amazingly well and years later is still keeping parts moving well on things I made a couple of years ago. When you first apply it, it will actually make the parts stick to each other. Do not force the parts to move when they are sticking. Wait about an hour or two for the lubricant to dry before turning the parts. After that make a few turns to check that it is turning well.
I printed all pieces at .2mm layer height with 2 shells and 10% infill. I set the slicer to do the shells from inside to outside on the heart pieces because that approach helps with the overhangs they have. I set the slicer to do the shells from outside to inside on the other pieces because that approach helps to ensure that outside dimensions are more exact for a better fit.
With that said, let’s get to the assembly. First you need to assemble the heart with the arrow pins. Start with the tail pin going through heart_2-3_piece_6_arrow. Make sure piece 6 spins freely on it. Then insert it into the one hole in the hear center that is bigger than the rest. The pieces assemble in the same orientation as the original Three Heart Gears that Emmett designed (see “Remixed from”). With the tail pin oriented vertically, The wide edge goes on top. See partial assembly picture for reference of how the pieces should be oriented for assembly. Heart_2-3_piece_5_arrow goes on the opposite side of the heart as the tail pin. Do not attach the arrow point pin yet. Insert the arrow point pin through the hole in the small ring and make sure that it turns freely. With it slid all the way in, there should be enough room to lock the tail pin in the opposite hole. Then lock the arrow point pin into piece 5 of the heart. At this point, you should be able to hold on to the small ring and turn the arrow point pin that sticks out to turn the heart. I hooked up that pin to a drill to turn it for a while to break it in. I then added more CRC Heavy Duty Silicone lubricant into every crack, let it sit for a couple of hours and then turned it again. See this video of it turning on the drill:
When I wasn’t holding the camera and could hold the ring more securely, I actually was able to spin it quite fast with the drill. Be careful though, because pieces can potentially fly off at high speeds if it is going fast. I recommend using a moderate speed like I used in the video.
I used my drill to help break it in at each opportune point in the assembly.
The arrow point pin then attaches to the large ring in the fixed hole. The 8x20 pin goes through the opposite hole in the large ring and locks into the small ring. Lubricate it. Make sure of course that the pin spins freely. At this point, you should be able to turn the small ring and heart gears with the 8x20 pin (I used the drill to work this in). Attach the large gear to this pin. Insert an 8x11 pin into the next fixed hole. Lubricate the small gear and attach it to the 8x11 pin. Again a reminder to let lubricated parts dry. Now you should be able to turn the small gear to turn the large gear to turn the small ring to turn the heart gears. It is important to ensure that everything turns freely with each new part you add so that you can recognize when something is sticking.
Next you attach another 8x11 pin in the hole beside the small gear and attach the right upright. Lubricate it of course. On the other side of the right upright, you attach the heart with an 8x11 pin. On the other side of the large ring, attach the left upright using the 8x22 pin through the hole in the left upright. The uprights attach to the bottom brace with a friction fit. I used the drill one last time at this point. Attach the drive gear to the 8x22 pin and attach the crank to the drive gear.
That should do it.
Now show your valentine how amazing a 3D printed valentine can be!