Practical 3D prints: Making helpful container caps

3D printing project: Learn how one simple design technique can solve a variety of practical problems.

Welcome back to The Fab Lab. In the video above we're going to do another practical 3D printing project. This time what we're going to look at building end caps for containers.

Today we're going to learn how to make two different kinds of end caps, and these are really simple. All they really boil down to is two cylinders, one of which is hollowed out. I'll show you how to do both in TinkerCAD. The first one I'm going to make was a request from my wife to take a pill cup and create a cap for it, so that's what I did.

Creating that kind of flat cover is about as simple as it can get. The hardest part is really just getting the diameter right across the top of the cap so that it fits snugly. As the associated video shows, start with a cylinder. In TinkerCAD, duplicate that cylinder so you have a second one. Make that just a little bit bigger because we actually want the space for the hole.

In the video, you'll initially see that there's one mistake. I created a ring, not a cap. What do we need to do to make it work? Just move the cap hole up a millimeter or so, depending on how thick you want the top of the cap. Now we group it together and you have a cap.

That's all there is to it. You can make caps that fit just about anything.

I also wanted to show you how I get the size right. What I do is, after I design it, I export it from TinkerCAD or Fusion 360, bring it into my slicer, and then lower the model down so there's just a little bit showing. This becomes really clear in the video, where the outcome is lowering the print time allowing repeated testing until the tolerances are just right.

The other item I showed in the video was a cap for a vice handle. The process is very similar to the first cap we looked at, with two small additions. We're going to be adding a little screw hole so that we can screw this thing on and hold it to the wooden part. Then, we're going to be adding a little dome at the top to just make it look better on the wooden handle.

The video shows how to add a sphere to the top of the cap, along with another cylinder used to bore a hole in the side of the cap for a screw. There will be some inevitable drooping of molten filament spanning the gap inside the cap, but because it's hidden and secured with a mechanical fastener, the drooping won't ever be noticed.

And there you go. 3D printing doesn't have to be hard and it doesn't always have to be about printing novelty items. 3D printing can be simple and useful and solve an immediate, tangible problem in a very short time. The cap in the video took me maybe 10 minutes in TinkerCAD to design up and maybe 30 minutes to print.

Is it a big project? No. Is it a practical project? Oh yeah. Go out there and build, make, design 3D print something awesome. If you design and make something cool (especially if it's simple and practical), let us know in the comments below.

You can follow my day-to-day project updates on social media. Be sure to follow me on Twitter at @DavidGewirtz, on Facebook at Facebook.com/DavidGewirtz, on Instagram at Instagram.com/DavidGewirtz, and on YouTube at YouTube.com/DavidGewirtzTV.

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