As I was making bath bombs to give for Christmas I felt a little heartburn. I reached for the Alka Seltzer... Wow... $8.99 for 36 tablets! One dose is made of 2 tablets, so that comes to 50 cents per dose. Then I looked at the active ingredients. Citric acid and sodium bicarbonate. Exactly what I was using for the bath bombs! Sour salt and baking soda! I made a rapid calculation: one dose comes to 2 grams of citric acid, and 3.88 grams of baking soda. If I figure that citric acid costs $4/lb and baking soda is $1/lb, the exact same dose of alka selzer's active ingredients would cost me about 2.5 cents to make myself.... Twenty times less than the store bought version! OK to be fair, I didn't figure the cost of filler, and the store bought alka selzer also contained aspirin, but I neither needed nor wanted the aspirin. Even if you end up spending more on the citric acid and less for the Alka Seltzer than I did, you'll still come out ahead.
Last month, engineer Shane Wighton of Stuff Made Here impressed the Internet with his curiously engineered wooden basketball backboard that helps the ball into the hoop. (Video below.) His latest version, above, employs computer vision and robotics to track the ball and tilt the backboard to direct the ball through the basket.
Russian artist Roman Booteen modifies coins with incredible engravings and feats of mechanical engineering. This coin features a beating heart. Other exquisite examples of his work are below. He also customizes Zippo lighters. (via Kottke) View this post on Instagram #hobonickel #goldinlay #morgandollar #engraved #engravedcoin #hobonickel #hobonickels A post shared by Roman Booteen (@romanbooteen) on […]
What’s your biggest gripe about power strips? Since most power servers like that are pretty standard these days, your beef probably isn’t about performance or connectivity. No, the biggest rap on trying to use many power strips is the curious engineering decision that often leaves multiple oddly shaped plugs and charging units unable to all […]
Between work, family obligations, and just getting to bed at a decent hour, we all have a lot on our plates these days. So, it’s easy for things like grooming and skincare to never be a high-priority issue. That is until they become a high priority issue. Like when your face constantly breaks out. Or […]
Today’s teachers extol the virtues of hands-on learning, the method of helping students, particularly the youngest children, learn through basic doing. From trial-and-error methods to practice honing their emerging skills, youngsters can soak up a world of learning opportunities when their developing minds are unleashed. While the thought of dropping a smartphone or tablet into […]