Recovering Nichrome Wire From Unexpected Sources

April 10, 2014 by James Hobson 41 Comments

115b-guitar-hero

Don’t you hate it when you’re in a pinch and all your favorite surplus or electronic stores are closed? You’ve gotta finish this project, but how? He’s a nice real hack for you guys. How to recover nichrome wire from a ceramic heater!

Necessity spawned this idea, as [Armilar] needed to make 45 cuts in two pieces of foam in order to ship some long circuit boards. Not wanting to make the 90 cuts individually, he improvised this nichrome slicing jig. Not having a spool of nichrome handy, he decided to use a less conventional method. He pulled out a sledgehammer and smashed open a ceramic wirewound resistor.

According to him, nice big ceramic resistors like this 10W one have about a meter of nichrome wire inside! After breaking the ceramic, it’s quite easy to remove. He made up a jig using nylon spacers and rivets, and then wrapped his wire back and forth across the whole length. It worked perfectly — though he was using 240VDC @ about 1.2A…

If you don’t need such a complex setup, there’s always the bare bones wire foam cutters we’ve featured many times before.

Using Nichrome Wire To Repair Broken Plastic Parts

February 5, 2013 by Mike Szczys 44 Comments

nichrome-wire-plastic-repair

It’s a real bummer when injection molded plastic parts break. We’ve never found a gluing technique that works for a part which is exposed to force like the clamp on this camera tripod. But [Matthias Wandel] may be on to something. Here he’s using nichrome wire to reinforce the broken plastic part.

The repair process is demonstrated in full in the video after the break. He scavenged the wire from the heating element of broken hair driers. the idea is to wrap the wire across the broken piece, then apply power from a bench supply. This heats the wire, which can then be pulled beneath the surface of the plastic. [Matthias] likens it to using rebar in concrete.

His implementation could be improved just a bit. Getting the wire to embed evenly is a problem, but using a pair of pliers instead of just alligator clips may yield better results.

Continue reading “Using Nichrome Wire To Repair Broken Plastic Parts” →

Hot Wire Foam Cutter Does Circles, Too

December 2, 2020 by Kristina Panos 3 Comments

Foam is all kinds of useful, but trying to cut it with scissors or a serrated plastic knife is usually an exercise in futility. What you really need is a hot wire for nice clean cuts. [Elite Worm] built a hot wire foam cutter that can cut any type of foam with ease, be it Styrofoam or grey craft foam.

There are a ton of ways to heat up a taut piece of nichrome wire, but few of them are as good looking as this one. [Elite Worm] designed and printed a table with an adjustable fence so it can be used like a table saw. There is also a circle-cutting jig that looks really handy.

This design uses a 12 V power regulator to heat up a piece of tension-adjustable nichrome wire for buttery smooth cuts. This thing looks fantastic all the way down to the cable management scheme. All the files are available on Thingiverse if you want to build one for yourself, but you’ll need to use something other than PLA.

This wire cutter is pretty versatile, but you could go even smaller with a handheld version, or build a larger, CNC-based machine.

Continue reading “Hot Wire Foam Cutter Does Circles, Too” →

Hot Wire Ribbon Cutter Ceremoniously Heats Up Productivity

March 16, 2020 by Kristina Panos 8 Comments

Anyone who’s ever cut ribbon, grosgrain or otherwise, may be dismayed by the frayed edge. There are methods of avoiding this, like cutting the ribbon diagonally, or double-diagonally into a forked point, or cutting it straight across and cauterizing the threads with a lighter. But if you have a thirteen dozen baker’s dozens’ worth of goodies to festoon, ain’t nobody got time for that.

[IgorM92] made this hot wire ribbon cutter for his wife, who has a yummy-looking baking business. It combines the cutting and the heat-sealing into a single step by using the heating element from an old soldering iron. If you don’t have one of those, you could just as easily use the nichrome wire from an old hair dryer, a toaster, or wire-wound resistor.

Since the idea is essentially shorting a power source to heat up a wire, it should be done safely. [IgorM92] used a phone charger to condition mains power down to 5 V. There isn’t much else to the circuit, just a rocker switch, a power-indicating LED, and its resistor, but this simple project will no doubt save a lot of time and labor. Burn past the break to watch it ramp up production.

Nichrome wire is good for cutting foam, too. Here’s a bare-bones version that can be made in minutes.

Continue reading “Hot Wire Ribbon Cutter Ceremoniously Heats Up Productivity” →

CNC Hot-Wire Cutter Gives Form To Foam

February 1, 2020 by Dan Maloney 12 Comments

Rapid prototyping tools are sometimes the difference between a project getting off the ground and one that stays strictly on paper. A lightweight, easy-to-form material is often all that’s needed to visualize a design and make a quick judgment on how to proceed. Polymeric foams excel in such applications, and a CNC hot-wire foam cutter is a tool that makes dealing with them quick and easy.

We’re used to seeing CNC machines where a lot of time and expense are put into making the frame as strong and rigid as possible. But [HowToMechatronics] knew that the polystyrene foam blocks he’d be using would easily yield to a hot nichrome wire, minimizing the cutting forces and the need for a stout frame. But the aluminum extrusions, 3D-printed connectors. and linear bearings he used still make for a frame stiff enough to give clean, accurate cuts. The addition of a turntable to the bed is a nice touch, turning the tool into a 2.5D machine. The video below details the construction and goes into depth on the toolchain [HowToMechatronics] used to go from design to G-code, including the tricks he used for making a continuous path, as well as integrating the turntable to make three-dimensional designs.

Plenty of hot-wire foam cutters have graced our pages before, everything from tiny hand-held cutters to a hot-wire “table saw” for foam. We like the effort put into this one, though, and the possibilities it opens up.

Continue reading “CNC Hot-Wire Cutter Gives Form To Foam” →

Wire Wound Resistors On Your Own

July 21, 2018 by Al Williams 17 Comments

In all kinds of engineering, we build on abstractions in a kind of inverted pyramid. Lots of people can, for example, design a system using ready-made building blocks on printed circuit boards. Fewer people can do the same design using ICs. Fewer still can design with components. But who designs the components? Even fewer people. Then there are the people designing the constituent elements of those components. [Learnelectronics] wanted to break one of those abstraction layers so he shows how to make your own wire-wound resistors.

Wire-wound resistors are often used when you need resistance with a higher power dissipation than a common film or composition resistor. Using nichrome wire makes this more practical since a meter of it has nearly 20 ohms of resistance. A regular wire has much less resistance. The video shows a drill winding a coil of wire neatly, but this also highlights one of the problems with wire wound resistors.

Continue reading “Wire Wound Resistors On Your Own” →

Robotic Muscles From Fishing Line And Nichrome

July 11, 2018 by Donald Papp 19 Comments

Did you know that under the right conditions, nylon can be used as a type of artificial muscle? We certainly didn’t until we came across [Brandon T. Wood]’s Material Linear-Actuator for Robotics entry for the 2018 Hackaday Prize.

When [Brandon] first learned about Nylon Linear Material Actuators (NLMAs), he became determined to find a repeatable and practical method of making and experimenting with them. This is how it works: hyper-wound coils of nylon, when heated, will contract along their length while expanding in width. Upon cooling, they return to their original shape.

[Brandon] has been busy mainly with the kind of work that is important but not very flashy: finding accessible methods to reliably create strands of artificial nylon muscles cheaply and reliably. His current method uses a jig to wind nylon fishing line until it coils upon itself tightly, then twist a length of nichrome wire around the outside to act as a heater. Using this method, the coils can be electrically controlled. [Brandon] is currently experimenting with creating bundles of individual nylon coils to act all together as one big muscle, because while one wire isn’t particularly strong, a bundle could be quite another story. It’s definitely unusual and is doing a lot of work to turn a known phenomenon into something hackable, which makes it lovely to see in this year’s Hackaday Prize.