Restoration of Antique Clock With Unique Oscillator
Adding Wire Races Improves 3D-Printed Bearings
Like a lot of power transmission components, bearings have become far easier to source than they once were. It used to be hard to find exactly what you need, but now quality bearings are just a few clicks away. They're not always cheap though, especially when you get to the larger sizes, so knowing how to print your own bearings can be a handy skill.
Of course, 3D-printed bearings aren't going to work in every application, but [Eros Nicolau] has a plan for that. Rather than risk damage from frictional heating by running plastic or metal balls in a plastic race, he uses wire rings as wear surfaces. The first video below shows an early version of the bearing, where a pair of steel wire rings lines the 3D-printed inner and outer races. These worked OK, but suffered from occasional sticky spots and were a bit on the noisy side.
The second video shows version two, which uses the same wire-ring race arrangement but adds a printed ball cage to restrain the balls. This keeps things quieter and eliminates binding, making the bearing run smoother. [Eros] also added a bit of lube to the bearing, in the form of liquid PTFE, better known as Teflon. It certainly seemed to smooth things out. We'd imagine PTFE would be more compatible with most printed plastics than, say, petroleum-based greases, but we'd be keen to see how the bearings hold up in the long term.
Maybe you recall seeing big 3D-printed bearings around here before? You'd be right. And we've got you covered if you need to learn more about how bearings work -- or lubricants, for that matter.
Thanks to [Nick Dunham] for the tip.
#mischacks #3dprinting #ballbearing #bearing #composite #lubricant #powertransmission #ptfe #races #teflon #wire
Three Ways to Detect the Silver Ball
We speak from experience when we say that making pinball targets is harder than you might think. The surface area of the part of the ball that touches is oh-so-small, and you really need to have gravity on your side for best results. Luckily, [TechnoChic] did the work for us and came up with these three versatile sensor designs that would be good for any game, not just pinball. They all use fresh, pristine cardboard from the Bezos Barn and a conductive fabric tape made by Brown Dog Gadgets that they call maker tape.
With the possible exception of not being solderable (can you solder it? ours hasn't showed up yet), maker tape is seemingly superior to copper tape because it is designed to be conductive in the Z-direction, and if you've ever laid out a copper tape circuit, you know that tape overlaps are pretty much par for the course.
First on the list is the track switch, which we think is pretty much necessary. After all, what fun is a pinball machine without at least one pair of rails to ride? Might as well score some points at the same time. This one looks to be the trickiest since the rails have to be consistently spaced, otherwise the ball will fall. The drawbridge target uses a cardboard hinge and the weight of the ball to force two pieces of tape together to complete the circuit.
The flappy hole target is probably our favorite because it's the most adaptable. You could use it for all kinds of things, like getting the ball to a basement level of a pinball game, or if you want to be evil, set it up in the drain area and deduct points every time you lose the ball, or just use it to trigger the next ball to drop. This one would also be really good for something like Skee-Ball and would really keep the BoM cost down compared to say, IR break-beam targets or coin slot switches.
You can check out these sensors in a brief demo after the break, and then see how [TechnoChic] put these ideas to use in this winter-themed pinball machine we showed you a few weeks ago.
#games #howto #ballbearing #cardboard #conductivetape #makertape #pinball #pinbox3000
BEAM-Powered, Ball-Flinging Beam Has Us Beaming
We have a soft spot for BEAM projects, because we love to see the Sun do fun things when aided by large capacitors. [NanoRobotGeek]'s marble machine is an extraordinary example -- once sufficiently charged, the two 4700 μF capacitors dump power into a home-brew solenoid, which catapults the ball bearing into action toward the precipice of two tracks.
[NanoRobotGeek] started with the freely-available Suneater solar circuit. It's a staple of BEAM robotics, slightly modified to fit the needs of this particular project. First up was verifying that the lever (or beam, if you will) principle would work at all, and [NanoRobotGeek] just built it up from there in admirable detail. The fact that it alternates between the swirly track and the zigzag track is entrancing.
There are several disciplines at play here, and we think it's beautifully made all around, especially since this was [NanoRobotGeek]'s first foray into track bending. We love the way it flings the ball so crisply, and the track-changing lever is pretty darn satisfying, too. You can check it out in action in the video after the break.
Although this was [NanoRobotGeek]'s maiden marble track, it's not their first circuit sculpture -- check out this flapping, BEAM-powered dragonfly.
#classichacks #solarhacks #ballbearing #beam #marblemachine #solarpanel #solarpower #solenoid
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