It’s safe to say most Hackaday readers would love to have a mill at home, or a nice lathe, but such equipment isn’t always practical for the hobbyist. The expense and amount of room they take up is a hard sell unless you’re building things on them regularly, so we’re often forced to improvise. In his latest video, [Eric Strebel] gives some practical advice on using a standard drill press to perform tasks you would normally need a mill or lathe for; and while his tips probably won’t come as a surprise to the old-hands out there, they might just …read more http://pje.fyi/Q1qM1C
If you’ve had the classic engineering education, you probably have a hazy recollection of someone talking about control theory. If you haven’t, you’ve probably at least heard of PID controllers and open loop vs closed loop control. If you don’t know about control theory or even if you just want a refresher, [Brian Douglas] has an excellent set of nearly 50 video lectures that will give you a great introduction to the topic. You can watch the first lecture, below.
You might think that control systems are only useful in electronics when you are trying to control a process like …read more http://pje.fyi/PwH3dG
If you have about an hour to kill, you might want to check out [Shahriar’s] video about the Stanford Research SR530 lock in amplifier (see below). If you know what a lock in amplifier is, it is still a pretty interesting video and if you don’t know, then it really is a must see.
Most of the time, you think of an amplifier as just a circuit that makes a small signal bigger in some way — that is, increase the voltage or increase the current. But there are whole classes of amplifiers designed to reject noise and the lock …read more http://pje.fyi/Pqybz9
[Andrew Sink] made a brief video demonstrating how he imported an STL of the well-known 3D Benchy tugboat model, and instead of sending it to a 3D printer used the Brick Mode feature to make a physical copy out of LEGO bricks in an eye-aching kaleidoscope of colors.
For those of you who haven’t used Tinkercad lately, Brick Mode allows you to represent a model as LEGO bricks at various scales. You model something as usual (or import a model) and by pushing a single button, render it in LEGO as accurately as can be done with standard bricks.
In …read more http://pje.fyi/Pn70TQ
Engraved acrylic lights up nicely with LED lighting. Simply engrave clear acrylic with a laser engraver, then edge-light the acrylic and watch the engraving light up. This badge made by [Solarbotics] shows how they used this principle when creating some pendants for an event that performed particularly well in the dark.
The pendants they created have two engraved acrylic panels each, and that’s about it. Two LEDs and a CR2032 battery nestle into pre-cut holes, and the engraved sides are placed face-to-face, so the outer surfaces of the pendant are smooth. By using some color-cycling RGB LEDs on one panel …read more http://pje.fyi/PbQw57
The image shown is the mineral Hackmanite, which fluoresces under ultraviolet lighting. However, not all UV is created equal, and that makes a difference if you’re into UV imaging. The image for this article is from [David Prutchi] and shows the striking results of using different wavelengths of UV. [David] goes into detail on how to make your own DIY Long, Medium, and Short-wave UV Illuminator complete with part numbers and wiring diagram. The device isn’t particularly complicated; the real work was determining the exact part numbers and models of lamp, filters, and ballasts required to get the correct results. …read more http://pje.fyi/PZ5Lxc
Here’s a rec-room ready hack: an automatic drink dispenser.
[truebassB]’s dispenser operates around a 555 timer, adjusted by a potentiometer. Push a button and a cup pours in a few seconds, or hold the other button to dispense as much as you want.
The dispenser is made from MDF and particle board glued together, with some LEDs and paper prints to spruce it up. Just don’t forget a small spill sink for any miscalculated pours. You needn’t fret over the internals either, as the parts are easily acquired: a pair of momentary switches, a 12V micro air pump, a brass …read more http://pje.fyi/PXzMMs