What’s the deal with getting things done? There’s a Seinfeld anecdote that boils down to this: get a calendar, do a thing, and make a big X on each day that you do the thing. Pretty soon, you’ll thirst for chains of Xs, then you’ll want to black out the month. It’s solid advice.
[3D Printy] likes streaks as well, and made several resolutions at the beginning of 2022. As the first of 30 videos to be made throughout the year, they featured this giant 3D printed counting mechanism (video, embedded below) that uses empty filament spools, some 3D prints, and not much else. These are all Hatchbox spools, and it won’t work for every type, but the design should scale up and down to fit other flavors.
This isn’t [3D Printy]’s first counter rodeo — he’s made several more normal-sized ones and perfected a clever carryover mechanism in the process, which is of course open-source. So each spool represents a single digit, and there are printed parts in the core that make the count carry over to the next spool. Whereas the early counters used threaded rod, this giant version rides on 2.5 mm smooth rod, so the spools can slide apart easily. But how does everything stay together? A giant elastic band made of TPU filament, of course — because the answer is always in the room.
Check out the video after the break, and stay for the 900%-sped-up assembly at the end.
Continue reading “Empty Spools Make Useful Tools, Like Counters”
When you really start fine-tuning your 3D printer, you might start to notice that even the smallest things can have a noticeable impact on your prints. An open window can cause enough of a draft to make your print peel up from the bed, and the slightly askew diameter of that bargain basement filament can mess up your extrusion rate. It can be a deep rabbit hole to fall down if you’re not careful.
One element that’s often overlooked is the filament spool; if it’s not rotating smoothly, the drag it puts on both the extruder and movement of the print head can cause difficult to diagnose issues. For his custom built printer, [Marius Taciuc] developed a very clever printable gadget that helps the filament roll spin using nothing but the properties of the PLA itself. While the design might need a bit of tweaking to work on your own printer, the files he’s shared should get you most of the way there.
All you need to do is print out the hubs which fit your particular filament spools (naturally, they aren’t all a standard size), and snap them on. The four “claws” of the hub lightly contact a piece of 8 mm rod enough to support the spool while limiting the surface area as much as possible. The natural elasticity of PLA helps dampen the moment that would result if you just hung the hub-less spool on the rod.
The STL files [Marius] has provided for his low-friction hubs should work fine for anyone who’s interested in trying out his design, but you’ll need to come up with your own method of mounting the 8 mm rod in a convenient place. The arms he’s included are specifically designed for his customized Prusa Mendel, which is pretty far removed from contemporary desktop 3D printer design. Something to consider might be a piece of 8 mm rod suspended over the printer, with enough space that you could put a couple spools on for quick access to different colors or materials.
Hackers have been trying to solve the spool friction issue for years, and as you might expect we’ve seen some very clever designs in the past. But we especially like how simple [Marius] has made this design, and the fact that you don’t need to source bearings to build it. If you’re thinking of giving this new design a shot, be sure to leave a comment so we know how it worked out for you.
Continue reading “Printable Filament Spool Hub Skips The Bearings”
We’ve been seeing an influx of repurposed 3D printers recently. Thrifty hackers have been leveraging cheap 3D printers as a way to bootstrap their builds, on everything from laser engravers to pick and place machines. There’s nothing wrong with that, and honestly when you can get a cheap 3D printer for less than the cost of the components separately thanks to the economies of scale, you’d be foolish not to.
But there’s still something to be said for the classic RepRap mentality of building things using printed parts and smooth rods. Case in point, the largely 3D printed plotter that [darth vader] sent in for our viewing pleasure. This isn’t somebody sicking a pen on the extruder of their open box Monoprice special, this is a purpose built plotter and it shows. In the video after the break you can see not only how well it draws, but also how large of a work area it has compared to a modified 3D printer.
If you know your way around a 3D printer, most of it should look pretty familiar to you. Using the same GT2 belts, steppers, end stop switches, and linear bearings which are ubiquitous in 3D printers, it shouldn’t be difficult to source the parts to build your own. It even uses a Mega 2560 with RAMPS 1.4 running Marlin 1.1.9 for control.
The biggest difference is the physical layout. Since there’s no heavy hotend or extruder assembly to move around, the plotter has a cantilever design which gives it far greater reach. As it only needs to sightly lift the pen off the paper, there’s no need for a complex Z axis with leadscrews either; a simple servo mounted to the end of the arm is used to raise and lift the pen. We especially like the use of a tape measure as strain relief for his wiring, a fantastic tip that we (and many of you) fell in love with last year.
While it’s hard to beat just tossing a pen onto the business end of your desktop 3D printer in terms of convenience, we think it’s pretty clear from this build that the results don’t quite compare. If you want a real plotter, build a real plotter.
Continue reading “The 3D Printed Plotter You Didn’t Know You Needed”