The techniques for making single-digit quantities of custom molded parts don’t scale well when you need to make dozens, as [Kevin Holmes] discovered. He needed to make 80-some sets of a silicone motor mount, and the one-up mold process was not going to work. He explores several solutions, which he rejects as being too complicated. Finally [Kevin] comes up with the idea of daisy-chaining banks of molds clamped together with rails of stock metal bars. It’s a pretty nifty process to watch and you can check the video out below, which is not unlike a very slow 7495 four-bit shift register.
Even though the silicone he uses is clear, pay attention and you can still see the carry-out as it propagates from mold to mold. He manually performs the nibble carry operation from one bank to the next — we wonder if he could cascade these banks, and inject all 80 in one really big squeeze?
Why would someone need 80 sets of silicone rubber motor mounts, you may ask? Well, you may remember the 4-mation 3D zoetrope that we wrote about back in 2018. [Kevin] is one of the founders of this mesmerizing project, and it would seem that their Kickstarter project has been successful. As he demonstrates in the video below, without some type of noise dampening mounts, a rumble from the motor is amplified through the stage of the zoetrope. If you have any favorite mold-making tips for small batch manufacturing, let us know in the comments below. Thanks to [George Graves] for sending this tip our way.
Continue reading “Serial Silicone Molding”
The Apple Watch was the tech company’s attempt to bring wrist computers into the mainstream. It’s naturally available in a variety of fits and finishes, but if you want something properly original, you’ve got to go custom. [Useless Mod] does just that with a clear case for the popular smartwatch.
The mod starts with a patient, careful disassembly of the watch – necessary given the delicate components inside. It’s achieved in the end with only having to drill out 1 screw and an unfortunately snapping of the crown wheel axle. However, [Useless Mod] presses on, and silicone casts the original Apple enclosure. The video goes over all the finer points, from degassing to using strips of acrylic plastic to act as runners. Once done, the silicone mold is used to produce a replica case in transparent epoxy, and the watch is reassembled.
The final result is impressive, with the case optically clear and showing off the watch’s internals. The look is improved by removing some of the original insulation tape to better reveal the PCBs inside. Unfortunately, the design of the watch, which is largely covered by a screen and heartbeat sensor, means it’s not the greatest choice for a clear case mod, but it works nonetheless. We’ve seen similar work before from [Useless Mod] too – like this transparent drone case for the Mavic Mini. Video after the break.
Continue reading “Apple Watch Gets Custom Transparent Case”
If you’ve got one of something and you want more, duplicating it with a silicone mold can be a great way to go. This is applicable to 3D printing something you need many copies of, and a whole variety of other usecases. [Eric Strebel] prides himself on his abilities in this area, and has put out a guide to producing very large silicone molds in a simple and reliable manner.
The overarching process is simple, but followed properly, it produces great results. [Eric] starts by building a mold box out of wood, coated in shellac to ensure it doesn’t stick to the silicone. The master part is then stuck to the base, surrounded by a lasercut cardboard strip which acts as a seal and key. Once properly degassed silicone is poured in and cured, the second half can be made. The mold is flipped in the mold box, the seal key removed, and release agent applied to the silicone surfaces. With another pour and cure, the mold is ready for casting new parts.
While simple, if the correct equipment isn’t used or steps skipped, you’ll end up with a useless mold full of air bubbles or surface irregularities. It’s useful to see just what it takes to get a mold of such scale (13″ x 19″!) completed without flaws. We’ve featured [Eric]’s work before, such as his fine detail improvements on the Apple Pencil. Video after the break.
Continue reading “Making Silicone Molds – Big Ones!”
Making silicone molds seems easy, but there are a lot of missteps to be made along the way that can mean the difference between a great, reusable mold, and one that’s a sad waste of silicone. If you’re helpless to know the difference, then check out [Eric Strebel]’s 9-minute masterclass teaser video on making a two-part mold for resin casting, which is also embedded below.
Even if you already know how to do this, there’s probably a good tip in here somewhere. One of them being that you should always pour your silicone from one place and let it coat the piece being copied. Otherwise, there might be lines on the mold. Another tip is for DIY mold release made from petroleum jelly thinned with naphtha.
Our favorite tip has to do with the way [Eric] makes this a reusable two-part mold, which is more akin to injection molding. To pour silicone for the second part and get it to separately nicely, [Eric] uses sprues made out of resin rods that were cast inside of drinking straw molds. These he chamfers against a belt sander to minimize the contact with the cast part, which makes them a snap to break off. [Eric] says this is just the beginning, and there are more videos to come that will break down the steps.
There’s more than one way to make a mold, especially for casting in metal. We’ve seen everything from 3D-printed molds to kinetic sand.
Continue reading “Mold-Making Masterclass In Minutes”
Hackaday Editors Tom Nardi and Mike Szczys comb through their favorite hacks from the past week. We loved Donald Papp’s article on considerations before making the leap from FDM 3D Printers to a resin-based process, and we solidify our thoughts on curing cement in low-gravity. Tom’s working on a Cyberdeck build, and he also found an ancient episode of an earlier and much different version of the Hackaday podcast. We’re impressed with a mostly 3D-printed useless machine, a thermal-insert press that’s also 3D-printed, and the Raspberry-Pi based Sidekick clone that popped up this week. A DIY wire-bending robot is an incredible build, as is the gorgeous wire-routing in a mechanical keyboard, and the filigree work on this playing card press. Plus you need to spend some time getting lost in this one hydrogen-line telescope project.
Take a look at the links below if you want to follow along, and as always tell us what you think about this episode in the comments!
Direct download (53.5 MB)
Places to follow Hackaday podcasts:
Continue reading “Hackaday Podcast 038: Cyberdecks Taking Over, Resin 3D-Printing Vs FDM, Silicone Injection Molding, And The Pickle Fork Fiasco”
RFID payment systems are one of those things that the community seems to be divided on. Some only see the technology as a potential security liability, and will go a far as to disable the RFID chip in their card so that it can’t be read by a would-be attacker. Others think the ease and convenience of paying for goods by tapping their card or smartphone on the register more than makes up for the relatively remote risk of RFID sniffers. Given the time and effort [David Sikes] put into creating this contactless payment ring, we think it’s pretty clear which camp he’s in.
Alright, so the whole ring making part sounds easy enough, but how does one get an RFID chip that’s linked to their account? Easy. Just call the bank and ask them for one. Of course, they won’t just send you out a little RFID chip and antenna to mount in your hacked up project. (If only things were so simple!) But they will send you a new card if you tell them your old one is getting worn out and needs a replacement. All you have to do when it gets there is liberate the electronics without damaging them.
[David] found that an hour or so in an acetone bath was enough to dissolve the plastic and expose the epoxy-encased RFID chip, assuming you scrape the outer layers of the card off first. He notes that you can speed this part of the process up considerably if you know the exact placement and size of the RFID chip; that way you can cut out just the area you’re interested in rather than having to liquefy the whole card.
Once you have your chip, you just need to mount it into a ring. [David] has designed a 3D printable frame (if you’ve got a high-resolution SLA machine, that is) which accepts the chip and a new antenna made from a coil of 38 AWG magnet wire. With the components settled into the printed frame, its off to a silicone mold and the liberal application of epoxy resin to encapsulate the whole thing in a durable shell.
If a ring is not personal enough for you, then the next step is getting the RFID chip implanted directly into your hand. There are even folks at hacker cons who will do that sort of thing for you, if you’re squeamish.
Continue reading “RFID Payment Ring Made From Dissolved Credit Card”
Plastic is a highly useful material, but one that can also be a pain as it ages. Owners of vintage equipment the world over are suffering, as knobs break off, bezels get cracked and parts warp, discolor and fail. Oftentimes, the strategy has been to rob good parts from other broken hardware and cross your fingers that the supply doesn’t dry up. [Eric Strebel] shows us that’s not the only solution – you can replicate vintage plastic parts yourself, with the right tools.
In the recording industry there’s simply no substitute for vintage gear, so a cottage industry has formed around keeping old hardware going. [Eric] was tasked with reproducing VU meter bezels for a classic Neve audio console, as replacement parts haven’t been produced since the 1970s.
The first step is to secure a good quality master for replication. An original bezel is removed, and polished up to remove scratches and blemishes from 40+ years of wear and tear. A silicone mold is then created in a plywood box. Lasercut parts are used to create the base, runner, and vents quickly and easily. The mold is then filled with resin to produce the final part. [Eric] demonstrates the whole process, using a clear silicone and dyed resin to make it more visible for the viewer.
Initial results were unfortunately poor, due to the silicone and hardener used. The parts were usable dimensionally, but had a hazy surface finish giving very poor optical qualities. This was rectified by returning to a known-good silicone compound, which was able to produce perfectly clear parts first time. Impressively, the only finishing required is to snap off the runner and vents. The part is then ready for installation. As a final piece of showmanship, [Eric] then ships the parts in a custom laser-engraved cardboard case. As they say, presentation is everything.
With modern equipment, reproducing vintage parts like knobs and emblems is easier than ever. Video after the break.
Continue reading “Reproducing Vintage Plastic Parts In Top-Notch Quality”