Sometimes Square is Square: Basic Machinist Skills

Is it possible to make an entertaining video about turning a cube of aluminum into a slightly cubier cube? As it turns out, yes it is, and you might even learn something along with the sight gags and inside jokes if you watch [This Old Tony] cover the basics of squaring up stock.

Whether you’re working in wood or metal, starting with faces that are flat, smooth and perpendicular is the key to quality results. [Tony] is primarily a machinist, so he works with a nice billet of aluminum and goes through some of the fundamental skills every metalworker needs to know. When you’re working down to the thousandths of an inch it’s easy to foul up, and tricks such as using a ball bearing between the vise jaws and the stock to prevent canting are critical skills. He covers tramming the mill, selecting which faces to cut and in which order, and ways to check your work on the surface plate and make any corrections if and when things go wrong. Look for cameos by fellow machinist [Abom79] and [Stefan Gotteswinter], including one with [Stefan] in a very compromising position. But a ball in a vise and no [AvE] reference? C’mon!

[Tony] makes a potentially tedious subject pretty entertaining by keeping things light, and we appreciate both the humor and attention to detail. He’s turned out some great videos that we’ve covered before, like making your own springs or a shop-built boring head, and his stuff is really worth checking out.

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This piggy bank is our stock broker


[Johna and Justin] are working to take the emotion out of playing the market. They built this piggy bank which automatically purchases stock when your coinage totals the cost of a single share. That’s right, just turn the selector to one of your three chosen stocks (Google, Facebook, and Apple are used in this example) and plug in some coins. The bank counts your money, compares it to the current online stock price, and pulls the trigger if you have enough dough. You can check out a demo clip after the jump.

The hardware is rather simple thanks to Adafruit’s programmable multi-coin acceptor. It handles the cash and it’s pretty easy to interface with the Arduino which handles the rest of the work. It connects to a computer via USB, depending on a PHP script to poll the current price. We dug through the code repository just a bit but didn’t find the snippet that does the actual stock purchase. Whether or not they actually implemented that, it’s certainly an interesting concept.

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