I have been doing a bad job keeping track of how quickly my 3D-printed ultralight fingertip mouse project, the Li’l Magnum!, has been progressing. I took the first photos on January 8, so that means I have been using this mouse in one form or another for about a week. That isn’t a long time, but I have learned a lot so far.

I am still waiting for the non-Pro version of the VXE Dragonfly R1 to arrive. The screw holes and microswitches on its circuit board (PCB) should line up with my design, but I don’t think the tray that adds lateral strength for the grips will line up quite right. There is a make of my mouse on Printables. It seems to be working, but the PCB doesn’t match mine! I wonder which version of the mouse that is?

I can’t make the frame compatible with the cheaper version of the mouse until it arrives, so I am at a bit of a standstill. It seems like a good time to talk about what I have learned in the past week.

You shouldn’t daily drive a fingertip mouse

I am doing it because it is helpful to eat your own dog food. I want to dial things in so the buttons feel as locked in as possible. I want the grips to line up exactly where they need to be. I want my tiny mouse to feel right, so I am using it as much as possible to expose the flaws.

I am also trying to get good at using such a light mouse while playing Team Fortress 2, and I was more than a little worried that switching back and forth between a 21-gram mouse and an 87-gram mouse might hinder my progression.

There is nowhere to rest your hand when using a fingertip mouse. Your hand is always at the ready. You can’t just relax, read a few paragraphs, then spin the scroll wheel. You are always holding your fingers somewhere.

I find myself perching my thumb and ring finger on TOP of the side grips when I am heavily using the scroll wheel. It is very weird, and the sharp top edges of the grips aren’t exactly comfortable.

Using the mouse for productivity tasks has helped with the design. I think I have things dialed in quite nicely now. I am not completely certain that everyone’s PCB and microswitches will match mine, but at least I am understanding what it takes to dial in a good feel.

I know this is contradictory to the heading up there, but I think you SHOULD daily drive your new fingertip mouse. Not for forever! Just until you get the feel for it in your favorite games.

I am testing out some grip tape

The VXE Dragonfly R1 Pro game with a bunch of custom-shaped grip tape. It is grippy, but hate the way the texture feels on my fingers. What I do love is that the tape is just a bit squishy.

I manually cut some pieces down to fit my mouse buttons and the side grips. I love it and I hate it.

My mouse looks a big goofy, because this free grip tape has silly patterns on it.

The grips only added 0.25 grams, which is nice. The texture feels weird, which is a bummer. The tape is soft, which is really nice.

I didn’t have any trouble with my fingers slipping off the mouse. I am grabbing the sides, so my thumb and fingers don’t go anywhere. My buttons have a bit of a texture from the layer lines from the 3D-printing process, so I don’t think I really need the grip tape on the buttons.

This will come down to personal preference. It looks like I can buy full sheets of grip tape, and it would be easy to laser cut them into exactly the right shapes.

Getting the clicks to feel exactly right is challenging!

There are little plungers on the flappy paddles that engage the microswitches for the left and right mouse buttons. If they are too long by 0.16 mm, then the button will be stuck. If they are too short by 0.16 mm, then you have to push the end of the paddle an extra 1.2 mm to get the button to click.

I have also found that if the plungers are JUST BARELY too long that the button feels like it will click if you just breath on it. It sounds like this should make for an extremely responsive mouse, but it doesn’t feel great in practice.

There are all sorts of great ways to make the length of the plungers adjustable, but they all add weight, and we really don’t want to be adding weight. The less tension I put in the spring mechanism for the buttons, the more leeway we have in setting the plunger length. I think this will get dialed in over time as more people print the mouse and report back on whether the prints are coming out too loose or too tight.

I feel like I have done a good job getting the spring tension, plunger lengths, and post-travel stops set up correctly. I rarely have a print where things don’t feel right now, though I do have the occasional weird snot of plastic that doesn’t land well on the support material.

The bummer is that this works for me, with my circuit board, with my printer, and with my microswitches. It wouldn’t take much for yours to not fit quite as well as mine!

How long is a PLA mouse shell going to last?

I am more than a little torn here. PETG, ABS, or ASA would all stand up to the repeated flex of clicking much longer than PLA, and ABS would save around 0.5 grams of weight. I did test prints in both PETG and ABS. Both were soft and too weak with my lightweight PLA settings.

I would either need to tweak the slicer settings to beef up the weakest parts of the print for PETG or ABS, or I would need to redesign the weak areas. I am not excited about maintaining two or three sets of parameters for every mouse circuit board that my 3D model supports.

PLA is awesome because anyone with a 3D printer has a really good chance of printing their own fingertip mouse shell. That is more than enough reason for me to stick with PLA.

I would enjoy being able to stock these in my store at a reasonable price, but I want to bang on a PLA mouse for at least a few weeks before I even think about attempting this. You’d think I would already have a week’s worth of clicks into one of my mice by now, but I seem to find an excuse to make a tweak and print a new frame every single day!

Do you even want or need a fingertip mouse?

Most people probably shouldn’t own a fingertip mouse. It is really nice having a 20-gram mouse when playing Team Fortress 2. It is probably giving me a slight edge over using the R1 Pro at its full original 49 grams, but that really only matters here because I am playing on a team against 12 other human players. A slight advantage doesn’t matter if you’re playing Red Dead Redemption 2 or Borderlands 3!

You can buy a 36-gram VXE Mad R mouse with an 8K receiver for $46. That is about what I paid for my VXE R1 Pro, but it is lighter and comes with a better receiver. You could also spend a little more on a 30-gram Zen 8K. If you could have regular mouse that weighs 30 or 36 grams, do you really need a 21-gram fingertip mouse?

I didn’t choose the Dragonfly R1 Pro because it was the lightest mouse for the price. I chose it because there is also a $19 version with slightly reduced specifications. Maybe you don’t want to spend $150 to try a Zeromouse Blade. Maybe you don’t want to take apart a $50 mouse to try my fingertip mouse mod.

I don’t know about you, but I would spend $19 and print 6 grams of PLA to try out an ultralight mouse. I might hate it, but who cares?! It is a fun project. Even if you hate it, you can put original mouse back together and have a nice 52-gram mouse.

The $19 Dragonfly R1 was out of stock, so I ordered a $22 Dragonfly R1 SE. Both of these mice share the same PCB, but I believe my R1 SE will come with a larger battery that is 3 or 4 grams heavier.

battery  pcb  wheel lens li'lmagnum final w/skates SE+ 9.5/520  9.2  2.04  1.2             26.24 pro 5.2/250  9.9  2.04       3.2        21.16

Conclusion