Quick home foundry to melt aluminium

Today I decided to take a creative break and turn our old Weber grill into a foundry… because who doesn’t want to melt down old hard drives and turn them into art?

Aluminum ring
A quick and dirty “ring” cast from aluminium

There are a number of ways to build a home forge using paint cans, flower pots, chimney pipes and more, but while planning out my strategy last night I came across a YouTube video by “LifeBuzzN” which used an old grill. Our old grill sitting behind the trash cans was just asking to get the treatment. First to Goodwill to pick up an old hair dryer then a quick trip to Home Depot (and then the requisite second trip to get the part I overlooked) and I was ready to go.

Grill turned into a foundry
Home foundry courtesy of Weber and Vidal Sassoon

The setup is pretty simple, 1.5″ pipe is bolted to the bottom of the grill and an old hair dryer acts as an always-on bellows to get the coals extra hot. I used an old cast iron pot I also picked up at Goodwill to act as my crucible. After a half a day of tinkering and learning I figured out just what was needed to turn old hard drives into aluminum mini-muffins (ingots, if you must).

Aluminum ingots cast in a muffin tin
Aluminium ingots ready for reheating and casting.

Since I had the forge going and a bunch of molten metal I had to try a quick casting. I made a hasty form out of some foam insulation and buried it in a bucket of sand. This “lost foam” casting process is quick and easy, leveraging the low boiling point of foam to have it boil away when molten metal is poured in. If you’re careful with your foam form and use a coating to keep the sand out you can get really clean results. I wasn’t careful, I was just to enthusiastic to try out my new toy. The result wasn’t pretty, but it was mine.

Cast aluminum ring held in pliers
My aluminum ring with sprue still attached.

 

Next up I’m going to try getting refined and use the lost wax casting process. I’ve ordered some casting wax from Amazon, so I should be ready to try to create something a bit more refined this weekend.

Tweeting washer and dryer for Arduino with Ethernet

My tweeting washer and dryer have been running great for a bit now and I’ve done some code cleanup to make it less embarrassing to share. The code attached to the post  is designed to use an Arduino Ethernet shield, not the WiFly module from the original example. If you already changed your tweeting dryer to use an Ethernet shield you can probably just download this code and upload it with little-to-no modification.

Download the Arduino code, circuit diagram and PHP files from my Git repo: WasherDryerMessenger

I’ve added a number of things to my code which weren’t in the original. I have, however, put them behind configs so I believe you should be able to use the code without hardware changes.

Here are two relevant configs at the top of the code:

  1. #define WASHER 0: In the sample code I have tweeting for the washing machine turned off. If you add another current sensor to your hardware you can turn this on to get tweets from your washer too.
  2. #define WEBMSG 0: This setting enables pulling the pithy tweets from a database on the web. Before enabling this there is some setup required, see: Getting a random string from MySQL for Arduino

If you want to have a tweeting washer as well as dryer, the hardware change you’ll need to make is to duplicate the current sensing circuit already in place for the dryer and add a third LED. In the diagram below left I have recreated the original circuit from Thomas’s Dryer Messenger in breadboard format (click for full size). On the right I show the added washer circuit (note: Ethernet shield not shown for simplicity).

Breadboard circuit diagram  Circuit diagram for washer and dryer

When you finish the modified circuit you can test it by plugging the dryer into the new transformer jack and updating the dryer pin setting in the code. Only after you’ve tested the hardware should you plug in both appliances and turn on the washer tweeting using the WASHER define (see the configuration notes earlier in this post). If you want the same account to tweet both washer and dryer status you can duplicate your dryer OAuth token for the washer on line 103. I elected to have separate handles for my washer and dryer and obtained a second OAuth token from Arduino-tweet.appspot.com.

At this point you should have a tweeting washer and dryer but you’ll notice the tweets are the same every time and rather boring. To add variety back to your tweets you should follow my instructions for enabling the WEBMSG for getting random tweets from a database on the web: Getting a random string from MySQL for Arduino.

Have you added a washer to your setup? Share your washer’s twitter handle in the comments below.