For many of us, the bane of electronic projects is making a professional-looking enclosure. Sure, 3D printing has made it easier to make the actual enclosure, but there’s still the problem of labeling it. [Richard Langner] has the answer with something he calls easy front panels. You can read about it or watch the tutorial video below.
The concept is easy enough. You create your beautiful artwork in your choice of graphics programs. The example uses Inkscape, but you could do it in anything, even PowerPoint. You print it out and cut it to size. You could, of course, print it in color or — as the example does — color it in by hand.
Last time we talked about how Marlin has several bed leveling mechanisms including unified bed leveling or UBL. UBL tries to be all things to all people and has provisions to create dense meshes that model your bed and provides ways for you to adjust and edit those meshes.
We talked about how to get your printer ready for UBL last time, but not how to use it while printing. For that, you’ll need to create at least one mesh and activate it in your startup code. You will also want to correctly set your Z height to make everything work well. Continue reading “3D Printering: Getting Started With Universal Bed Leveling”→
Have you ever wondered how an electronic wind vane translates a direction into a unique signal? It seems as though it might be very complicated, and indeed some of them are. [martinm] over at yoctopuce.com has an excellent writeup about measuring wind direction using just a single, easily printed disk and some phototransistors.
Commercial weather vanes often use complicated multi-tracked disks with magnets and reed switches, conductive traces and brushes, or some other means of getting a fine resolution. Unfortunately some of these are prone to wear or are otherwise more complicated than they need to be.
What makes [martinm]’s solution unique is that they have applied previous research on the subject to a simple and durable 3d printed wind vane that looks like it’ll be able to handle whatever global warming can throw at it. The encoder’s simplicity means that it could likely be used in a large number of applications where low resolution position sensing is more than enough- the definition of a great hack!
Adding more tracks or even more disks would enable higher resolution, but the 12 degree resolution seems quite good for the purpose. Such a neat wind vane design will surely be welcome if you want to 3d print your own weather station. Thanks to [Adrian] for the great tip!
There’s an old saying about something being a “drop in the ocean.” That’s how I felt faced with the prospect of replacing a 12 V heated bed on my printer with a new 24 V one. The old bed had a nice connector assembled from the factory, although I had replaced the cable long ago due to heating issues with that particular printer. The new bed, however, just had bare copper pads.
I’m no soldering novice: I made my first solder joint sometime in the early 1970s. So I felt up to the challenge, but I also knew I wouldn’t be able to use my usual Edsyn iron for a job like this. Since the heated bed is essentially a giant heatsink for these pads, I knew it would require the big guns. I dug out my old — and I mean super old — Weller 140 W soldering gun. Surely, that would do the trick, right?
[Integza] is on a mission to find as many ways as possible to build rockets and other engines using 3D printing and other accessible manufacturing techniques. He had an a great idea – is it possible to 3D print a solid fuelled rocket, (video, embedded below) specifically can you 3D print the rocket grain itself? By using the resin as a fuel and mixing in a potent oxidiser (ammonium perchlorate specifically – thanks for the tip NASA!) he has some, erm, mixed success.
Effective thrust vs grain cross-sectional profile
As many of us (ahem, I mean you) can attest to, when in the throes of amateur solid-propellant rocket engine experimentation (just speaking theoretically, you understand) it’s not an easy task to balance the thrust over time and keep the combustion pressure within bounds of the enclosure’s capability. Once you’ve cracked making and securing a nozzle within the combustion chamber, the easiest task is to get control of the fuel/oxidiser/binder (called the fuel grain) ratio, particle size and cast the mixture into a solid, dry mass inside. The hard part is designing and controlling the shape of the grain, such that as the surface of the grain burns, the actively burning surface area remains pretty constant over time. A simple cylindrical hole would obviously increase in diameter over time, increasing the burning surface area, and causing the burn rate and resulting pressure to constantly increase. This is bad news. Various internal profiles have been tested, but most common these days is a multi-pointed star shape, which when used with inhibitor compounds mixed in the grain, allows the thrust to be accurately controlled.
[Integza] tried a few experiments to determine the most appropriate fuel/binder/oxidiser ratio, then 3D printed a few fuel grain pellets, rammed them into an acrylic tube combustion chamber (obviously) and attached a 3D printed nozzle. You can see for yourself the mach diamonds in the exhaust plume (which is nice) due to the supersonic flow being marginally over-expanded. Ideally the nozzle wouldn’t be made from plastic, but it only needs to survive a couple of seconds, so that’s not really an issue here.
The question of whether 3D printed fuel grains are viable was posed on space stack exchange a few years ago, which was an interesting read.
Although the widespread use of 3D printers has made things like linear bearings and leadscrews more common, you still can’t run down to your local big-box hardware store and get them. However, you can get drawer slides and any hobby shop can sell you some RC servos. That and an Arduino can make a simple and easy plotter. Just ask [JimRD]. You can also watch it do its thing in the video below.
Of course, servos aren’t usually what you use in a plotter. But the slides convert the rotation of the servo into linear motion. One servo for X and one for Y is all you need. Another microservo lifts the pen up and down using a hinge you could also get from a hardware store.
USB cables inevitably fail and sometimes one end is reincarnated to power our solderless breadboards. Of course, if the cable broke once, it is waiting to crap out again. Too many have flimsy conductors that cannot withstand any torque and buckle when you push them into a socket. [PROSCH] has a superior answer that only takes a couple of minutes to print and up-cycles a pair of wires with DuPont connectors. The metal tips become the leads and the plastic sheathing aligns with the rim.
The model prints with a clear plus sign on the positive terminal, so you don’t have to worry about sending the wrong polarity, and it shouldn’t be difficult to add your own features, like a hoop for pulling it out, or an indicator LED and resistor. We’d like to see one with a tiny fuse holder.
![USB to Dupont adapter by [PROSCH]](https://hackaday.com/wp-content/uploads/2022/01/2022-01-01-USB-to-DuPont-adapter-feat.jpg?w=600&h=450)
