[Florian] has a few arcade games and MAME machines, and recently he’s been trying to embed objects in those hard plastic spheres on the end of joysticks. A common suggestion is to 3D print some molds, but even though that’s a great idea in theory the reality is much different: you’re going to get layer lines on the casting, and a mirror finish is impossible.
No, a silicone mold is the way to do this, but here 3D printing can be used to create the mold for the silicone. Instead of a few pieces of hot glued cardboard or a styrofoam cup, [Florian] is 3D printing a a container to hold the liquid silicone around the master part.
After printing a two-piece part to hold both halves of a silicon mold, [Florian] put the master part in, filled it up with silicone, and took everything apart. There were minimal seam lines, but the end result looks great.
In addition to making a 3D printed mold container, [Florian] is also experimenting with putting 3D printed parts inside these joystick balls. The first experiment was a small 3D printed barrel emblazoned with the Donkey Kong logo. This turned out great, but there’s a fair bit of refraction that blows out all the proportions. Further experiments will include a Pac-Man, a skull, and a rose, to be completed whenever [Florian] gets a vacuum chamber.
With resin printers slowly making their way to hackerspaces and garages the world over, there is a growing need for a place to cure these UV resin prints. No, they don’t come out of the machine fully cured, they come out fully solid. And no, we’re not just leaving them in the sun, because that’s not how we do things around here.
[Christopher] whipped up a post-cure lightbox meant to sit underneath his Form 1 printer. It’s made of 1/2″ MDF, with adjustable feet (something the Form 1 lacks), a safety switch to keep the lights off when the door is open, and a motor to rotate the parts around the enclosure.
The light source for this lightbox is 10 meters of ultraviolet LED strips. The LEDs shine somewhere between 395-405nm, the same wavelength as the laser diode found in the Form 1 printer. Other than a bit of wiring for the LEDs, the only complicated part of the build was the motor; [Christopher] bought a 2rpm motor but was sent a 36rpm motor. The vendor was out of 2rpm motors, so a PWM controller was added.
It’s a beautiful build that shows off [Christopher]’s ability to work with MDF. It also looks great sitting underneath his printer, and all his parts are rock solid now.
There are only a few more days until The Hackaday Prize semifinalists need to get everything ready for the great culling of really awesome projects by our fabulous team of judges. Here are a few projects that were updated recently, but for all the updates you can check out all the entries hustling to get everything done in time.
Replacing really, really small parts
The NoteOn smartpen is a computer that fits inside a pen. Obviously, there are size limitations [Nick Ames] is dealing with, and when a component goes bad, that means board rework in some very cramped spaces. The latest problem was a defective accelerometer.
In a normal project, a little hot air and a pair of tweezers would be enough to remove the defective part and replace it. This is not the case with this smart pen. It’s a crowded layout, and 0402 resistors can easily disappear in a large solder glob.
[Nick] wrapped the closest parts to the defective accelerometer in Kapton tape. That seemed to be enough to shield it from his Aoyue 850 hot air gun. The new part was pre-tinned and placed back on the board with low air flow.
How to build a spectrometer
The RamanPi Spectrometer is seeing a lot of development. The 3D printed optics mount (think about that for a second) took somewhere between 12 and 18 hours to print. Once that was done and the parts were cleaned up, the mirrors, diffraction grating, and linear CCD were mounted in the enclosure. Judging from the output of the linear CCD, [fl@C@] is getting some good data with just this simple setup.
Curing resin and building PCBs
[Mario], the guy behind OpenExposer, the combination SLA printer, PCB exposer, and laser harp is chugging right along. He finished his first test print with a tilted bed and he has a few ideas on how to expose PCBs on his machine.
You don’t need props to test a quadcopter
Goliath, the gas-powered quadcopter, had a few problems earlier this month. During its first hover test a blade caught a belt and bad things happened. [Peter] is testing out a belt guard and tensioner only this time he’s using plywood cutouts instead of custom fiberglass blades. Those blades are a work of art all by themselves and take a long time to make; far too much effort went into them to break in a simple motor test.
Power for your breadboards. It’s a USB connector, a 3.3V voltage regulator, and a few pins that plug into the rails of a breadboard.
“Have you seen those ‘Portable battery chargers for smartphones?’ Well the idea of the device is based on it , but the difference here is the internet part.” That’s a direct quote from this Indiegogo campaign. It’s funny because I don’t remember losing my damn mind recently. Wait. It’s $200. Yep. Yep. Definitely lost my mind there.
Putting the Internet on a USB stick not weird enough? Hair Highways. Yep, human hair. It’s just embedding human hair into resin, cutting everything up into plates, and assembling these plates into decorative objects. As a structural material, it’s probably only as strong as the resin itself, but with enough hair set in layers perpendicular to each other, it would be the same idea as fiberglass. Only made out of hair.
Tesla is building a $30,000 car and Harley is building an electric motorcycle. The marketing line for the bike will probably be something like, “living life on your own terms, 50 miles at a time”.
PixelClock? It’s a 64×64 array of red LEDs built to be a clock, and low-resolution display. It looks blindingly bright in the video, something that’s hard to do with red LEDs.
After several months of work, [Greg] has completed one of the most polished LED clocks we’ve ever seen. It’s based on the WS2812 RGB LEDs, with an interesting PCB that allowed [Greg] to make a huge board without spending a lot of money.
The board is made of five interlocking segments, held together with the connections for power and data. Four of these boards contain only LEDs, but the fifth controller board is loaded up with an MSP430 microcontroller, a few capsense pads for a 1-D touch controller, and programming headers.
Finishing up the soldering, [Greg] had a beautiful LED ring light capable of being programmed as a clock, but no enclosure. A normal plastic case simply wouldn’t do, so [Greg] decided to try something he’d never done before: casting the PCB inside a block of resin.
A circular mold was made out of a piece of MDF and a router, and after some problems with clear resin that just wouldn’t cure, his ring light was embedded in a hard, transparent enclosure. Conveniently stuck in the mold, of course. The MDF had absorbed a little bit of the resin, forcing [Greg] to mill the resin ring free from the wood, with a lot of finish sanding to make the clock pretty.
It’s a clock that demonstrates [Greg]’s copious manufacturing skills, and also his ability to troubleshoot the problems that arose. While he probably won’t be casting things inside an MDF mold anymore, with the right tools [Greg] could easily scale this up for some small-scale manufacturing.
Visiting the Midwest RepRap Festival, you will, of course, find a ton of 3D printed baubles and trinkets. A slightly more interesting find at this year’s MRRF was a lot of resin cast parts from [Mark VanDiepenbos]. He’s the guy behind the RotoMAAK, a spinny, ‘this was in the movie Contact‘-like device designed for spin casting with resins. At the festival, he’s showing off his latest project, 3D printed resin molds.
With the right mold, anyone with 2-part resins can replicate dozens of identical parts in an hour. The only problem is you need a mold to cast the parts. You could print a plastic part and make a silicone mold to cast your part. The much more clever solution would be to print the mold directly and fill it with resin.
[Mark] printed the two-part rabbit mold seen above out of ABS, filled it with urethane resin, and chucked it into his RotoMAAK spin casting machine. Six minutes later the part popped right out, and the mold was ready to make another rabbit.
Continue reading “MRRF: 3D Printed Resin Molds”
If you’re playing along with Twitch Plays Pokemon, you might as well do it the right way: with the smallest Game Boy ever, the Game Boy Micro. [Anton] needed a battery replacement for this awesome, discontinued, and still inexplicably expensive console and found one in a rechargeable 9V Lithium battery. You get two replacement cells out of each 9V battery, and a bit more capacity as well.
Every garden needs garden lights, right? What does every garden light need? A robot, of course. These quadruped “Toro-bots” react to passersby by brightening the light or moving out of the way. It’s supposed to be for a garden that takes care of itself, but we’re struggling to figure out how lights will do that.
Flexiable 3D prints are all the rage and now resin 3D printers are joining the fray. The folks at Maker Juice have introduced SubFlex, a flexible UV-curing resin. The usual resins, while very strong, are rock solid. The new SubFlex flexible resins are very bendable in thin sections and in thicker pieces something like hard rubber. We’re thinking custom tank treads.
Remember this post where car thieves were using a mysterious black box to unlock cars? Looks like those black boxes have moved from LA to Chicago, and there’s still no idea how they work.
Have a Google Glass? Can you get us on the list? [Noé] and [Pedro] made a 3D printed Google Glass adapter for those of us with four eyes.