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Comment Re:Great, first, global warming, now global fatten (Score 2) 34

Did you completely flunk Physics??? Orbital speed is set by orbiting mass. . .

Well, it looks like you struggled in either physics or English. Your statement only bears meaning if the orbiting mass is any significant portion of the primary body. Even Jupiter is only 0.1% of the mass of the sun, so it's mass is irrelevant in computing its orbital velocity about the sun.

Comment Re:Why not lost wax? (Score 1) 49

I had the same thought recently. Shapeways offers parts printed in wax for casting. I question the value, though, as shipping may well warp waxy materials. There are also others selling materials intended specifically for lost investment casting. Still others thought to see whether PLA could be used directly for lost investment casting with good results. The author at the second link used foam strips, presumably because it's cheap and fast, which 3d printing generally isn't.

Comment Re:Use a hair dryer (Score 1) 347

A hair dryer also softens the decal, which tears. These remove decals very quickly. Most of the residue is gone, and you have no worries about overheating the paint. It's best done with a pneumatic die grinder with a mandrel. After the decal is removed, the use of rubbing compound removes the top layer of oxides from the paint, and only the fussiest of inspections will find any sign that there was ever a decal.

Comment Re:Fake Fake Fake! (Score 2) 276

I don't think that it delivers 1,600J, so much as it consumes 1,600J. Quoting the numbers you printed:

1.1g sabot
300 m/s (above 250 m/s, so let's be generous).

E = 0.5*M*V^2, so
E = 0.5*1.1*300*300 = 49,500mJ = 49.5J. So, the muzzle energy is about 1/30th of the energy it appears to be using.

Poking around a bit, I found a variety of velocities and masses for paintballs, so I'll posit that the muzzle energy of a paintball pellet varies between 12J-20J. So, assuming the pressure system is imparting similar energy as a paintball gun, this guy's rail is imparting a maximum of about 30J-38J to the slug, or about 1/50th of the energy consumed. No wonder his graphite sabot didn't reach a target.

Comment Re:techie thoughts on Alaska (Score 1) 284

it's also cyclical based on I think a 5 year average of the price of oil - that means it's going to start going down next year as gas starts to plummet

It's based on the fund income, which doesn't necessarily correlate to oil prices. The Alaska Permanent Fund Corporation manages a *widely* diversified portfolio. An oil income deposited into the fund becomes a part of the principal and may contribute to the income.

Comment Re:Not free money (Score 1) 284

The permanent fund is ultimately a rainy day fund. The distribution of the dividend from the permanent fund can be redirected into the state budget when it's needed. It's difficult to do politically, though.

Recognizing, I suppose, that the Permanent Fund dividend will be difficult to touch, there's a Statutory Budget Reserve (~1.7B, easy to draw from) and a Constitutional Budget Reserve (~$10.1B, harder to draw from). There are also a bunch of smaller savings accounts that do things like offset the high cost of electricity in the villages. All told, Alaska has about $70B in savings, and about $20B of that can be used directly for the budget. That $20B can fund the government at it's current budget for about 4 years without any of the permanent fund earnings.

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