Misc Hacks

4187 Articles

Build An Induction Heater And Become A Metalsmith

April 8, 2012 by 84 Comments

If you’ve ever wanted to forge, cast, or smelt metal, this project is right up your alley. It’s a 30 kVA induction heater built by [bwang] over on Instructables. It gets hot enough to melt and forge steel, iron, and aluminum.

An induction heater operates by surrounding the object to be heated with a coil carrying high frequency AC current. Basically, the entire setup acts like a huge transformer with a shorted secondary. To get these currents into a workpiece, [bwang] used a TL494 PWM controller as an oscillator. The output of the TL494 is filtered and amplified a few times to generate a huge amount of AC current.

Larger versions of [bwang]’s induction heater are found in foundries and forges all across the land; even though this small version sucks down 50 A out of a dryer or stove outlet, induction heating is very efficient. We’re actually wondering why we don’t see many home blacksmiths using induction heating, so we’ll leave that for our readers to discuss in the comments.

[sessions] reminded us of this induction heater from a few years ago. A little smaller, but still usable.

Displaying Bubbles In Mineral Oil

April 6, 2012 by 15 Comments

After he saw a ‘falling water display,’ [Matt] figured he could turn that idea on its head. He built a display that uses bubbles for pixels. Even though the build isn’t complete, we love the results so far.

[Matt] began his build constructing a tall, thin water tank out of acrylic. Eight solenoids were mounted in the base of the tank, attached to an aquarium air supply, plastic tubing, and one way valves. The first run of the bubble display didn’t go too well, but after adding dividers between each column the display started working.

With the dividers, [Matt] no longer had to worry about bubbles colliding or moving any direction but up. The bubbles weren’t moving consistently, so he replaced the water with mineral oil. Oil made a huge improvement, but the bubbles still float up at different speeds. [Matt] ascribes this to the unregulated air supply, but we’re thinking this problem could be mitigated with glycerine like the previous bubble display we saw.

It may still have some problems, but we love the result. Check out the video of bubbles in mineral oil after the break.

Continue reading “Displaying Bubbles In Mineral Oil” →

A Little Geneva Drive Made Of Wood

April 1, 2012 by 14 Comments

MDF Geneva drive in action

Long ago, before servo motors and linear actuators were common, clever mechanical devices were what engineers used to produce the needed motion for their processes. The CNC-cut Geneva Drive may not be fit for industrial use, but this type of device has been used in everything from film projectors to rotating assembly tables. The constant rotation of the driving wheel is translated into intermittent motion by the [Maltese cross] driven wheel.

The drive and Maltese cross section of this particular drive are made out of MDF with the exception of a putty material that the motor shaft press-fits into. The article claims that this is the only Geneva drive in existence made out of MDF, however, we’d love to see that proven wrong in the comments!

If you’d like to make one of these yourself, CAD and G-code files are given for the hand-cranked version that this Drive is based off of in a separate post.  If you’re not familiar with how a drive like this works, or would just like to see everything in action, be sure to check out the video of it after the break! Continue reading “A Little Geneva Drive Made Of Wood” →

Floppy Autoloader Takes The Pain Out Of Archiving 5000 Amiga Disks

March 31, 2012 by 71 Comments

floppy-autoloader

Archiving data from old floppy disks can be a tedious process at best. Poorly labeled disks combined with slow transfer speeds put it high on the list of things we would rather not do, and it turns out that [Dweller] was of the same opinion. With an estimated 5,000 floppies in his collection, he finally decided it was time to clean house.

With no idea of what was stored where, he decided the best way to go about the process was to read all of the disks, archiving everything, saving the sorting process for later. He originally started by building a floppy autoloader out of Lego Mindstorm parts, which looked good on paper, but performed pretty poorly.

He came across an old floppy duplicator on eBay and figured that since the machine was built for handling gobs of disks, that it was the perfect base for his autoloader. He pulled the mechanical bits from the machine, incorporating them into the rig you see above. He swapped out the duplicator’s brains for an Arduino, which allows him to batch copy his disks and save a picture of each label with little effort.

He says that the system works great, making his life a lot easier (and less cluttered!)

Check out the video below to see his floppy autoloader in action.

Continue reading “Floppy Autoloader Takes The Pain Out Of Archiving 5000 Amiga Disks” →

glue stick linear actuator

Glue Stick + Servo = Linear Actuator

March 29, 2012 by 24 Comments

What do you get when you cross a glue stick with a hobby servo motor? A linear actuator, of course! Although this could be done with other household implements, the form factor of this glue stick seems perfectly suited to sit on top of a servo horn.

The servo, as you might have guessed, has to be converted to rotate fully instead of the 180 degrees or so that is typical of these types of motors. The trick to this, and what really makes it shine in our eyes, is that instead of attaching two resistors in a normal continuous rotation mod, the potentiometer is used on the glue stick allowing for position feedback.

The resulting force from this gear-reduced actuator is quite impressive, giving an “err” (over 3 Kilograms) on the scale used for testing. [Gareth] or [Chiprobot] gives a great tutorial of how to make one of these after the break, but if you’d rather just see it in action, skip to around 8:20! Continue reading “Glue Stick + Servo = Linear Actuator” →

[Aaron] Shows Us What Life Would Be Like If [Bob Vila] Started Hacking Headphones

March 27, 2012 by 19 Comments

construction-headphones

[Aaron Horeth] had a pair of headphones that had seen better days, and before he tossed them out, he realized that he could use them to build a set of custom cans. He had always wanted a pair of headphones with a detachable cord to prevent damage when tripped over, and thought that his old set would be the perfect donor.

He swung by his local hardware store to peruse their collection of construction earmuffs, eventually finding a set that looked decent and didn’t cost an arm and a leg. Using construction earmuffs as the framework for his headphones gave him the durability he was looking for with the added bonus of being designed to deaden extraneous noise. Once he got them home he pulled the drivers from his old set of headphones installing them into the earmuffs, but not before he wired them up to support a breakaway input cable.

There’s no doubt that the modifications are simple, but we imagine they come in pretty handy when tinkering around the shop.