How To Make Your Own Springs for Extruded Rail T-Nuts

Open-Source Extruded Profile systems are a mature breed these days. With Openbuilds, Makerslide, and Openbeam, we’ve got plenty of systems to choose from; and Amazon and Alibaba are coming in strong with lots of generic interchangeable parts. These open-source framing systems have borrowed tricks from some decades-old industry players like Rexroth and 80/20. But from all they’ve gleaned, there’s still one trick they haven’t snagged yet: affordable springloaded T-nuts.

I’ve discussed a few tricks when working with these systems before, and Roger Cheng came up with a 3D printed technique for working with T-nuts. But today I’ll take another step and show you how to make our own springs for VSlot rail nuts.

Continue reading “How To Make Your Own Springs for Extruded Rail T-Nuts”

ABS: Three Plastics in One

It would be really hard to go through a typical day in the developed world without running across something made from ABS plastic. It’s literally all over the place, from toothbrush handles to refrigerator interiors to car dashboards to computer keyboards. Many houses are plumbed with pipes extruded from ABS, and it lives in rolls next to millions of 3D-printers, loved and hated by those who use and misuse it. And in the form of LEGO bricks, it lurks on carpets in the dark rooms of children around the world, ready to puncture the bare feet of their parents.

ABS is so ubiquitous that it makes sense to take a look at this material in terms of its chemistry and its properties. As we’ll see, ABS isn’t just a single plastic, but a mixture that takes the best properties of its components to create one of the most versatile plastics in the world.

Continue reading “ABS: Three Plastics in One”

Experimenting With Extruded Elements

Conventional 3D printing and other additive manufacturing methods are highly effective at producing parts of irregular geometries that are difficult or impossible to create with other methods. However, there is a whole set of compromises that come with it – material uniformity, strength, and size are just some that come to mind. There are, however, other techniques that can be used in conjunction with these technologies, and the use of so-called “extruded elements” may be one of them.

The idea is to break up large models into a series of smaller mutually interlocking pieces of an extruded form. This is done by importing an STL model into OpenSCAD and processing it with a special script. This script essentially intersects a matrix of extruded forms upon the original part geometry, allowing it to be printed as a series of seperate pieces that can later be assembled. The instructions are long and detailed, but are an accurate guide of how to create your own extruded element parts.

There are options to customise the process, allowing for filled and skeleton type extrusions and various ways of interlocking the parts. There are interesting implications for this technology, thanks to the benefits of interlocking parts. Particularly, it could have great benefits for the repair of damaged structures and for building objects that exceed the size of the build platform on a smaller 3D printer. The technique looks especially good for building up lightweight cores for big objects. [Toby] is working on a stand-up paddle board.

We look forward to seeing how this particular project develops. We’ve seen other techniques to build large printed structures, before, too – like this giant RC F1 car.

Camera Slide Pans and Tilts Camera Mechanically

A camera slider is a popular and simple project — just a linear slide, a stepper, and some sort of controller. Adding tilt and pan axes ups the complexity until you’ve got three motors, a controller, and probably a pretty beefy battery pack to run everything. Why not simplify with an entirely mechanical pan-tilt camera slider and leave all that heavy stuff at home?

There’s more than one way to program motion control, and [Enza3D]’s design uses adjustable rails to move the gimballed pan-tilt head through two axes of motion. One rail adjusts vertically to control tilt, while the other adjusts in and out relative to the slider to control pan. Arms ride on each rail and connect to the gimbals to swivel the camera in both dimensions while it travels down the manually cranked slide. It’s pretty clever and results in some clean, dynamic shots as in the video below.

Our quibble is that the “program” is only linear since the control rails are straight lengths of aluminum extrusion; seems to us that some sort of flexible control rails might make for more interesting shots. [Enza3D] has amply documented the build and is looking for feedback, so comment away. And if you don’t have a 3D printer to make the parts, wood works for a slider too.

Continue reading “Camera Slide Pans and Tilts Camera Mechanically”

Self-assembling Polymers Support Silicone 3D Prints

We all know what the ultimate goal of 3D printing is: to be able to print parts for everything, including our own bodies. To achieve that potential, we need better ways to print soft materials, and that means we need better ways to support prints while they’re in progress.

That’s the focus of an academic paper looking at printing silicone within oil-based microgels. Lead author [Christopher S. O’Bryan] and team from the Soft Matter Research Lab at the University of Florida Gainesville have developed a method using self-assembling polymers soaked in mineral oil as a matrix into which silicone elastomers can be printed. The technique takes advantage of granular microgels that are “jammed” into a solid despite being up to 95% solvent. Under stress, such as that exerted by the nozzle of a 3D printer, the solid unjams into a flowing liquid, allowing the printer to extrude silicone. The microgel instantly jams back into a solid again, supporting the silicone as it cures.

[O’Bryan] et al have used the technique to print a model trachea, a small manifold, and a pump with ball valves. There are Quicktime videos of the finished manifold and pump in action. While we’ve covered flexible printing options before, this technique is a step beyond and something we’re keen to see make it into the hobby printing market.

[LonC], thanks for the tip.

CNC Machine Boasts Big Bed, Impressive Power from Off-the-Shelf Parts

A lot of homebrew CNC machines end up being glorified plotters with a router attached that are good for little more than milling soft materials like wood and plastic. So if you have a burning need to mill harder materials like aluminum and mild steel quickly and quietly, set your sights higher and build a large bed CNC machine with off-the-shelf components.

With a budget of 2000 €, [SörenS7] was not as constrained as a lot of the lower end CNC builds we’ve seen, which almost always rely on 3D-printed parts or even materials sourced from the trash can. And while we certainly applaud every CNC build, this one shows that affordable and easily sourced mechatronics can result in a bolt-up build of considerable capability. [SörenS7]’s BOM for this machine is 100% catalog shopping, from the aluminum extrusion bed and gantry to the linear bearings and recirculating-ball lead screws. The working area is a generous 900 x 400 x 120mm, the steppers are beefy NEMA23s, and the spindle is a 3-kW VFD unit for plenty of power. The video below shows the machine’s impressive performance dry cutting aluminum.

All told, [SörenS7] came in 500 € under budget, which is a tempting price point for a machine this big and capable.

Continue reading “CNC Machine Boasts Big Bed, Impressive Power from Off-the-Shelf Parts”

Bachelor Builds Enormous Laser Cutter, Nobody Complains

Nothing says swinging 21st-century bachelor pad better than a laser cutter. To really make a statement, you want a custom-built, 100 Watt, 1200mm x 900mm laser cutter.

The bachelor in question, [drandolph], rightly points out that a $6,000 build that takes up a significant fraction of the floor space in one’s apartment is better attempted without the benefit of spousal oversight. Still, what spouse couldn’t love the finished product? With a custom aluminum extrusion frame (which barely made the trip from China intact) it’s a sturdy affair, and who could deny the appeal of the soft glow of an LED-illuminated work chamber? A custom exhaust system with sound-deadening, a water chiller for laser cooling, an Arduino-controlled status beacon – there’s even a 3-D printed beer holder on the control panel! And think of all the goodies that will come off the enormous bed of this thing. Note to self: make sure wife sees this post.

There are cheaper and smaller laser cutters, but what’s the point if you have the freedom to go big?

[via r/DIY]