Resin Stacking Proves Messy And Difficult

December 12, 2021 by Lewin Day 15 Comments

3D printers are typically the tool you use when you want a one-off quick prototype. However, more and more, they’re being used to produce things in quantity. [Uncle Jessy] decided to try out the resin stacking technique in order to quickly produce many figurines on his resin printer. However, not everything went exactly to plan.

The technique is simple. The idea is to produce many copies of an object in a single continuous print on a resin 3D printer. To achieve this, the object is cloned many times, and scaffolding is created to allow the stacking of multiple objects on top of each other. This must be done carefully to avoid ruining the geometry of the object, and similarly to support material, uses more resin in the process.

[Uncle Jessy] experimented several times, but ran into multiple issues with the process when trying to print out some small Magneto figurines. An initial experiment using a raft failed when the print fell off the build plate. With the raft removed, the second print failed as the scaffolding didn’t print quite right. Further tweaks and beefing up the scaffold improved things, and [Jessy] managed to print 93 figurines in a single operation.

It’s a useful technique if you want to print a ton of models on a resin printer in as short a time as possible. However, expect to spend plenty of resin as you refine the technique. You’ll also need a big wash tank to clean the prints during post-processing. Video after the break.

Continue reading “Resin Stacking Proves Messy And Difficult” →

Customize These 3D Printed Cases

December 12, 2021 by Al Williams 27 Comments

Building something, of course, requires your electronics skills. But packaging it is often an exercise in mechanics. You can buy off the shelf, of course, but sometimes it is hard to find just the right enclosure. You probably have a 3D printer, too, but sometimes 3D printing an entire case can be time consuming and isn’t always completely attractive. Enter [Johannes-Bosch] and Fusion 360. These 3D printed frames assemble into boxes and are easy to customize. The panels are aluminum, although we imagine you could substitute wood, acrylic, or even a 3D printed sheet of plastic, if you wanted to.

The video below shows some examples. If your German isn’t up to snuff, ask YouTube to automatically translate the subtitles and you’ll get the idea.

Continue reading “Customize These 3D Printed Cases” →

Vacuum Forming With 3D Printer Filament

December 11, 2021 by Tom Nardi 17 Comments

Even if they don’t have one themselves, we’d wager the average Hackaday reader is at least vaguely aware of how a vacuum former works on a fundamental level. You heat up a plastic sheet until it’s soft, then use a vacuum pump to pull the ductile material down onto an object and hold it there while it cools off. It’s easy to build a vacuum forming rig yourself, but small commercial units are cheap enough that it might not be worth your time. If everything goes to plan, the technique is a quick and effective way of duplicating items around the home and shop.

But we were recently tipped off to a variation of this classic technique that’s certainly worth further research. As demonstrated in a recent video, [Nathan Martinez] shows how 3D printed sheets can be used in place of the 5″ x 5″ squares of thermoplastic film that his imported vacuum former was designed to use. It’s easy enough to do: just model up a square with the appropriate 2D dimensions in your CAD package of choice, and extrude it to a height of about .5 mm.

A printed mesh pattern could be used to form custom shaped filters or strainers.

So what’s the advantage? Well for one thing, it’s cheaper. Though admittedly, not by much. Going rate on Amazon seems to be about 90 cents per sheet for the real stuff, and some back of the envelope math shows the printed version coming in at around 30 cents given nominal filament costs. Whether or not those savings are worth the extra effort is certainly debatable.

But that’s not really the most interesting part. With printed sheets loaded into the vacuum former, you’ve got access to a much wider array of materials to work with. For example, [Nathan] shows off some very interesting flexible pieces he was able to produce using sheets of TPU. You can also experiment with different surface textures. These can not only be used to give your vacuum formed pieces a bit of interesting visual flair, but could actually have some practical applications. In the video we see how a printed mesh could be formed over a piece to create a conformal air vent or filter.

To be sure, there’s some room for improvement here. Not all the pulls were successes, and [Nathan] says getting the printed sheets up to the proper temperature can be tricky. But when it works, it works quite well, and we think there could be some untapped potential in this unexpected melding of new and old methods of at-home plastic production.

Continue reading “Vacuum Forming With 3D Printer Filament” →

Build Your Own Submarine

December 10, 2021 by Al Williams 22 Comments

If you are tried of building things that fly, why not try a submarine like [DIYPerks] did? As you can see in the video below, the key is to control buoyancy, and the mechanism used is impressive. The sub has two giant syringes fore and aft to compress or decompress water. The plungers are now 3D-printed actuators that travel on a lead screw. Two high-torque motors and some batteries sandwiched in acrylic disks make up the rest. This is a big vessel — you won’t be trying this in your bathtub and maybe not even your pool unless it is a big one.

Of course, everything needs to be watertight. Instead of trying to waterproof a power switch, this sub uses a reed switch so that a nearby magnet can turn it on. Not an original idea, but we always think it is more elegant than seals and potting compounds.

Continue reading “Build Your Own Submarine” →

Simple Design Elevates This Mechanical Dot Matrix Display

December 7, 2021 by Dan Maloney 11 Comments

Don’t get us wrong — we love unique displays as much as anyone. But sometimes we stumble across one that’s so unique that we lack the basic vocabulary to describe it. Such is the case with this marble-raising dot-matrix alphanumeric display. But it’s pretty cool, so we’ll give it a shot.

The core — literally — of [Shinsaku Hiura]’s design is a 3D-printed cylinder with a spiral groove in its outside circumference. The cylinder rotates inside a cage with vertical bars; the bars and the grooves are sized to trap 6-mm AirSoft BBs, which are fed into the groove by a port in the stationary base of the display. BBs are fed into the groove at the right position to form characters, which move upwards as the cylinder rotates. Just watch the video below — it explains it far better than words can.

The clever bit is how the BBs are fed into the groove. Rather than have a separate mechanism to gate the feed port, there’s a backlash mechanism that opens the port when the motor powering the drum runs in reverse for a bit. It’s a clever use of cams to get the job done without adding an extra servo, which sort of reminds us of the design parsimony exhibited in his one-servo seven-segment display.

It’s not clear that this would be a very practical display, but that doesn’t stop it from being cool. Although, [Shinsaku Hiura] just released a follow-up video showing a bigger version of this used to display upcoming events from Google Calendar, so perhaps we’re wrong. Continue reading “Simple Design Elevates This Mechanical Dot Matrix Display” →

Secret Ingredient For 3D-Printed Circuit Traces: Electroplating

December 6, 2021 by Donald Papp 45 Comments

Conductive filament exists, but it takes more than that to 3D print something like a circuit board. The main issue is that traces made from conductive filament are basically resistors; they don’t act like wires. [hobochild]’s interesting way around this problem is to use electroplating to coat 3D-printed traces with metal, therefore creating a kind of 3D-printed circuit board. [hobochild] doesn’t yet have a lot of nitty-gritty detail to share, but his process seems fairly clear. (Update: good news! here’s the project page and GitHub repository with more detail.)

The usual problem with electroplating is that the object to be coated needs to be conductive. [hobochild] addresses this by using two different materials to create his test board. The base layer is printed in regular (non-conductive) plastic, and the board’s extra-thick traces are printed in conductive filament. Electroplating takes care of coating the conductive traces, resulting in a pretty good-looking 3D-printed circuit board whose conductors feature actual metal. [hobochild] used conductive filament from Proto-pasta and the board is a proof-of-concept flashing LED circuit. Soldering might be a challenge given the fact that the underlying material is still plastic, but the dual-material print is an interesting angle that even allows for plated vias and through-holes.

We have seen conductive filament used to successfully print workable electrical connections, but applications are limited due to the nature of the filament. Electroplating, a technology accessible to virtually every hacker’s workbench, continues to be applied to 3D printing in interesting ways and might be a way around these limitations.

Rolling-Screw Extruder Goes Brushless

December 5, 2021 by Sonya Vasquez 33 Comments

In the name of saving weight and pushing plastic, it’s nice to see continuous tweaks on 3D printer extruders from folks in their spare time. And to go where no extruder has gone before, [wayne dalton] has managed to combine the rolling screw thread extruder concept directly onto a brushless pancake motor. The result is a filament pushing mechanism weighing in at just under 90 grams. What’s more, this modification arrives a few weeks weeks after we first saw an open source version of the rolling screw thread extruder land on Thingiverse back in September.

Getting a direct-drive BLDC extruder off the ground comes with a number of geometry challenges. First, filament needs to be fed through a motor with a hollow shaft. Since this motor will be operated under closed loop control via an ODrive, the motor also requires an encoder with a hole down the middle too. [wayne dalton] patiently walks us through all the changes made over seven iterations to produce a setup that will eventually mount onto a machine and start printing. But for that last step we’ll need to check back a bit later. Finally, this progress comes with the promise of a possible open source release of the design files, so we’re pretty eager to stay tuned for future videos.

In the last few years, we’ve seen state-of-the-art extruders move away from NEMA 17 motors in favor of more compact solutions like planetary gears and even lasers to push printers faster. We’re excited to see that folks keep trying to set the bar higher.

Continue reading “Rolling-Screw Extruder Goes Brushless” →