Building A Casting Furnace With Heat Exchanger

This completely DIY casting furnace turned out just great thanks to all the work [Biolit11] put into it along the way. He wanted to replace his older furnace with one that was more efficient, and to that end he built a heat exchanger into the design. This way the exhaust will preheat the intake air.

The furnace itself started with the shell of an old electric water heater. Excluding the design process, the majority of the build involved mold making. For circular parts he’s using quick tube, the paperboard forms used for pouring concrete footings. For more intricate parts he shaped polystyrene. They are layered in place and high-temperature cement is poured to form the permanent parts. After it hardens the polystyrene can be removed in chunks.

The heat exchanger is the part to the left. It includes several wide, flat pipes made of cement for removing the exhaust. Around those pipes a snaking metal chase carries the intake air which picks up the heat as it passes over the exhaust pipes.

For his first run with the new furnace he melted down a bunch of scrap aluminum and poured ingots.

[Thanks DC3]

Building A Coal Forge

We don’t get to see Blacksmith hacks around here too often. But even if they were rolling in on a weekly basis we think this one would be considered the special expanded edition with full-color centerfold. The sixty-five images in this coal forge build log are all commented and just begging to steal your attention for part of the afternoon.

The build mostly involves fabricating a system for injecting air into the forge and providing a mechanism for evacuating the waste ash. [BillDaCat] starts with a 3″ pipe as the ash dump, adding a latching door used to empty it when full. He then welds together a metal trough with a slotted bottom to hold the fiery fury, attaching the ash dump below. He uses a plasma cutter to add an opening in the upper portion of the ash dump for a blast gate.

If you’re excited about his build you should also check out the metal pour and the induction furnace.

[via Reddit]

Electromagnetic Field Camp

Emf Electromagnetic Field Camp is a three-day camping festival for people with an inquisitive mind or an interest in making things: hackers, geeks, scientists, engineers, artists, and crafters.

There will be people talking about everything from genetic modification to electronics, blacksmithing to high-energy physics, reverse engineering to lock picking, crocheting to carpentry, and quadcopters to beer brewing. If you want to talk, there’ll be space for you to do so, and plenty of people who will want to listen.

EMF is a volunteer effort by a non-profit group, inspired by European and US hacker camps like CCC, HAR, and toorcamp.  This year on Friday 31st August – Sunday 2nd September 2012 Will hold the first Uk meeting of its kind.

Events and activities will run throughout the day and into the evening, everything else (chats, debates, impromptu circus performances, orbital laser launches) will run as long as your collective energy lasts.

The Event is to be held at Pineham Park, Milton Keynes, UK.

As a Hackaday viewer you can get discounted tickets.

[thanks Jonty]

Iron Casting In The Parking Lot

Here’s one good thing about the bitter cold Midwestern winter, it helps keep you from overheating when working around a hot furnace. Back in February this iron pour happened in the parking lot of the Madison, Wisconsin based Sector67 Hackerspace. Look, they’re making iron hearts!

Now this isn’t just a bunch of members who got together and decided to do some casting. As you can tell in the video after the break the team knows what they’re doing. The event was a collaboration with FeLion Studios, a custom cast-iron art boutique. But the Hackerspace participants did get to take part in the process of building the cast, watching the pour, and cleaning up the rough results.

One of the people from FeLion Studios just appeared on the Martha Stuart Show, along with a 550 pound cast-iron frying pan United States map.  [Chris] from Sector67 tells us the New York frying pan that [Martha] is hold was a product of the parking lot pour.

Continue reading “Iron Casting In The Parking Lot”

Build An Induction Heater And Become A Metalsmith

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.

Smelting Metal In Your Microwave Oven

Grab some scrap metal and a microwave oven and you’ll be casting your own metal parts in no time. [Mikeasaurus], who is known for doing strange things like making Silly Putty magnetic or building his own spray paint bottles, doesn’t disappoint this time around. He read about microwave smelting in Popular Science and is giving it a shot himself.

The image above shows him pouring an ingot. He build an insulated brick enclosure inside of the microwave oven, then set it to go ten minutes for a 50/50 lead/tin mixture, or fifteen minutes for silver. This will vary based on the power rating of your microwave. You can see in the video after the break that the setup gave him some trouble shortly after pouring. It wasn’t a problem with the molten metal, but spontaneous combustion of the rigid foam insulation that did him in. We shouldn’t say ‘I told you so’, but that insulation says right on it that it’s flammable!

This isn’t the first time we’ve looked at casting metal melted in a microwave. Check out this other version posted back in 2005. Continue reading “Smelting Metal In Your Microwave Oven”

Hacking In Cameroon For Profit And Entertainment

[Bill Zimmerman] is in Cameroon and has been posting some really interesting articles about life in the central African nation. It comes as no surprise that imported goods can be prohibitively expensive for many of the country’s residents, so building tools and goods is way to improve life and save money. The image above is a metalworking cooperative where any number of products are manufactured from recycled materials, often using tools that the craftsmen made themselves. Their wares are amazingly wide-ranging; crow bars, motorcycle seats, buckets, plows, hammers, knives, cold chisels, and much more. The video after the break shows the tradesmen hard at work. See some video of the cooperative after the break.

But adults aren’t the only ones getting in on the action. Remember [William Kamkwamba] who built a wind generator for his villiage? It seems the tinkering spirit runs deep in the children of Cameroon as well. [Bill] came across some kids who grabbed leftovers like the soles of sandals, scraps of rope, and empty sardine tins to build a steerable toy car.

Continue reading “Hacking In Cameroon For Profit And Entertainment”