|Eggsact Egg Timer|
|This slick little gadget is the one
of the slickest little kitchen gadgets I've used. Obviously it times
boiling eggs but it does it in a unique manner.
It consists of two hunks of plastic with a color changing layer in between. This layer is red at room temperature. As it gets hot it turns black. Apparently the temperature where the color change occurs corresponds to the egg hardening temperature.
|The really slick part is
that the plastic absorbs and conducts heat at about the same rate as the
egg. Thus the black, the hardening process proceeds inward at the same
rate as with an egg.
This product is widely available at the better department stores. I think I got this one at Target.
|The unit itself showing the various layers.|
|Starting out. The water is boiling and the eggs and timer have just been added.|
|Finished, just like I like 'em. I like my boiled eggs with the yoke still dark yellow but not quite liquid. I do NOT like the yoke light yellow and dry.|
Centrifuge Formula spreadsheet
In discussion with a friend the subject of centrifugal oil cleaning came up. He's interested in running a stationary diesel on waste veggie oil and had found a product that purported to clean WVO by centrifuging it.
There's more scamming going on in the alternative fuels arena than at an Amway conference so I decided to do some math. I used a standard centrifuge formula from here. I put this formula in a spread sheet, used the viscosity of corn oil from here as pretty typical, got the density of the oil from here, assumed that the density of the particles to be removed would have to be similar to the oil to remain in suspension and selected 5 micron as the particle size. I ran the numbers for the smallest device, assuming that the rotor was 1/2 cm smaller than the housing and that 1/2 cm of oil builds up inside the rotor.
The equation computes the time to settle all the particles of that size. Bottom line, with the short transit time of the oil through this gizmo, it isn't going to bother 5 micron particles much at all. AT BEST, it'll maybe do about what a $10 oil filter will do.
The spreadsheet containing these numbers is at right. This is a general purpose centrifuge calculation so you can use it for other purposes. You can also play around with other assumptions for the gizmo in question
Can you imagine starting all those at once?
Click below if you want to see what happens when you try to steal copper from an energized line.