Compact Tinkercad Drill (+ Tinkercad Tips, Hacks, and Tools)

TLDR: I needed a drill. So I 3D printed a drill.

(Edit: Updated 8/21/2022 to include tips for using with smaller drill bits)

I am in the process of building a travel ukulele. I didn't have a bench vise when I used a power drill for the tuning peg holes - and resorted to holding the board between two boxes. I did a reasonably decent job of drilling straight down, but then I had to use one hand to hold things down and the holes were very slightly angled upwards. I had tried to drill the holes a little straight several times with the power drill, but it never quite worked.

I needed a new approach. What I really needed was a single hand operated, high precision, medium torque, low speed drill. This 3D printed tool can be used as a drill, screwdriver, and ukulele / guitar string winder and is small enough to fit inside your drill bit case.

Also, if you scroll to the bottom, I added several TinkerCAD tips, tricks, hacks, and tutorials - including screenshots, animated GIFs, and links to models so you can try these out for yourself. :)

To build this tool, you'll need:

1. A 3D printer
2. If you don't have one, perhaps a friend, local makerspace, or nearby library has one you could use
3. The STL file
4. You can download the STL for 3D printing or remix / adjust the design file over on TinkerCAD.
5. The TinkerCAD model includes two files. One of them is so you can print a thin cross section of the model to test fit with the screws and drill bits before printing the entire thing.
6. I've also uploaded a copy to this Instructable :)
7. If you just want to download the file, you can pick it up over on Printables
8. Filament
9. This model uses less than 2 meters / 5 grams / $0.13 worth of filament
10. Most give-away samples of filament spools have enough plastic to print about 20 drills
11. 3x #10-24 machine screws and matching nuts
12. You can buy a bag of 5x of these for under $1.50 at your local big box hardware store
13. Bonus: I've also uploaded the STL for the string winder and here's a link to the TinkerCAD model :)

Once you've 3D printed the model, there's really only one step - insert the nuts and machine screws.

When you're ready to use the drill, loosen the machine screws, insert the drill bit, screwdriver bit, or string winder, then tighten the three screws evenly.

Just loosen the screws and store everything back in the drill bit case!

This little drill actually works. It's not going to work fast and it's not intended for every project or every drill bit, but it may be what you need for your project or get be able to get you out of a jam in a pinch. In my case, I needed something I could operate with one hand and use with a lot of precision. This tool helped me drill a straighter hole into the side of my travel ukulele build than I ever would have been able to do with a power drill. I tried to do this with a power drill three times before getting it right with this tool!

Update: I needed to use the drill again for some small holes, so I wrapped my smallest drill bit in a thick rubber band, then tightening it into place. Worked great!

I suppose these TinkerCAD tips should technically come before the "put it all together" in step one. But, I used every one of these tips and tricks in making these models, so I figured why not share these too?

1. Hotkeys are super helpful:
2. "Ctrl-G" will Group objects
3. "Ctrl-Shift-G" will ungroup objects
4. "L" will show some Lines to aLign (get it?) objects which came in very handy for me
5. Hacks:
6. Holes. Making an object or shape a "hole" won't actually look like a hole at all until you group it with a solid object.
7. Grouping, Aligning, and then Ungrouping objects is a serious time-saving hack
8. In designing the string winder, I had to make sure some of the interior shapes were aligned with the exterior shapes, with a mixture of holes and solids. To do this, I aligned and grouped some of the parts, then aligned them with others, then ungrouped, and turned a few back into holes. This won't make a lot of sense until you start designing things, but as you do, just keep the idea in the back of your mind how switching up grouping/aligning/ungrouping can help achieve the shapes you need.
9. Start With A Dodecagon to Make Perfect Regular Polygons
10. I needed a hex "shaft" for my string winder, so it would fit into the drill. However, if you create a "hex" shape and then start to resize it, you end up skewing the hex so it's no longer a regular hexagon.
11. My "hack" was to make a hexagon, increase the sides to 12, scale it along the X and Y axes to the size I needed, then changed the number of sides from 12 down to 6, creating a perfectly sized hexagon. This would work well with a triangle, pentagon, etc as well!
12. You can see in the animated GIF above how using this method allowed me to scale a 20mm hexagon to a 15mm hexagon perfectly, while trying my best to eyeball it resulted in a slightly squished hexagon.
13. I've shared an animated GIF of this process plus created this TinkerCAD model so you can try for yourself.
14. Making & Deleting Parts is useful!
15. When making the drill, I was stumped on how to create a series of three evenly spaced holes (both for the cylinders and the nuts) in the drill. It's easy to spin a cylinder around it's midpoint - but I needed to spin the cylinder around a central point.
16. My "hack" was to make two cylinders, stack them on top of one another, then group them. When I rotated these, they were both rotated around the midpoint (which just so happened to be the seam between the two cylinders!). Once the doubled-cylinders were rotated exactly 120 degrees, I deleted the extra and, voila! I had perfectly positioned voids for the screws! (By grouping the boxes for the nuts with the cylinders, I was able to keep these positioned perfectly too).
17. I've created a screenshot so you can see how this works and a TinkerCAD model so you can try for yourself. You'll note I used yellow/red/orange colors to show the original shapes, when they were grouped/mixed, and when then the temporary shapes were deleted.
18. Tools:
19. I found this blog post of TinkerCAD hotkeys helpful.
20. This hexagon calculator helped me calculate some of the sizes I needed. There are a lot of shape calculators out there.

If you've read this far and thought my travel ukulele looks neat, it's based on the fantastic work, templates, videos, and instructions from Daniel Hulbert.

I've been working on it very slowly, a little bit at a time, usually before work, late at night, or on the weekends for about two months. If you have a lot of time on your hands and want to see 250+ progress photos and more than 15,800 words about my journey, I've been documenting my travel ukulele build journey on my website.