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Clayton Cramer's BLOG |
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Clayton's commentary on news and events of the day. Broadly speaking, I'm a conservative with libertarian sympathies (getting more conservative as my children get older).
 Never forget! I'm running for Idaho state senate I've written a number of history books, as well as scholarly and popular articles, (see my web page).
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Saturday, December 22, 2007
Suzuki Aerio SX AWD I drove a 2006 Suzuki Aerio SX all-wheel drive sedan yesterday. I was very impressed--even more so because the dealer was asking for $11,495 for one with only 9300 miles on it. It was nicely equipped, had adequate pep for an automatic--and it would be tempting solution to my snow problem. (Some people put bags of traction sand in the trunk of rear drive cars to solve the snow problem; right now, I have "traction ammunition" instead: a case of 7.62 mm NATO and several ammo boxes filled with pistol ammo. How Idaho!) When I looked at various consumer reviews of the Suzuki Aerio, I noticed a lot of reviews that said what a great car it was--but a disturbing new of complaints about it being nothing but trouble. One of my daughter's friends bought a new Suzuki Aerio last year--and it spent two months of the first year in the shop. It was all covered by warranty--but the combination of the various consumer criticisms (including my favorite: someone who complained about a bumper that fell off in a bad rainstorm, although I can't find that complaint online right now) and this close to home problem makes me wonder if the reason this particular Aerio is two years old--and still only has 9300 miles on it--is that it was in the shop too much to rack up any miles. Almost everyone agrees that Subarus are nearly indestructible--and it shows in the resale price. But perhaps I will just wait until summer, and plan to carpool with my wife when I have to go down the hill into Boise. Labels: cars Sinus Washes Instapundit points to an article about sinus washes as a treatment for sinus problems. I've been using NeilMed's product for several years, and I do think that they help. But I would say that the Breathe Right strips that I have discussed here have been more useful. Of course, it's not a choice; you can use both. One downside to sinus washes--you really need to clean the sink carefully afterwards to maintain domestic peace. There's no question that the saline wash removes stuff from your sinuses--the evidence is unmistakable. Labels: sinuses Wow! $1/Watt Solar Panels! One of the limiting factors on photovoltaics has been the cost. Most solar panels cost about $4 per watt (or more) for just the panel. Nanosolar claims to have shipped their first solar panels using a new process "which we believe will make us the first solar manufacturer capable of profitably selling solar panels at as little as $.99/Watt...." If so, they have crossed the line. Where I live, partly because hydropower makes electricity so cheap, solar panels have to cost $2/watt to be equal to what I can get from Idaho Power. If Nanosolar can actually sell photovoltaics at $1/watt--and assuming that they have a lifetime equivalent to other photovoltaics of 25-30 years--then solar will rapidly replace most other energy sources in the United States. It would even make nuclear power questionable, I suspect. Not only are we talking about something that will render coal, oil, and even hydropower obsolete, but it also means that pure electric cars start to look viable. Chevrolet's Volt concept car, for example, is a hybrid--but a rather interesting twist on the hybrid. The theory is this: "Seventy-eight percent of commuters drive 40 miles or less to and from work." The Volt is intended to carry enough of a charge that most people can plug it in at home every night, and never have the gasoline engine run. Also, unlike other hybrids, where the gasoline engine both recharges the batteries and directly drives the wheels, the Chevy Volt's engine only recharges the batteries: Substituting an electric generator for plug-in hybrids' internal-combustion engine simplifies the engineering process because it doesn't require managing multiple power sources, according to Posawatz, and it cuts costs by eliminating a mechanical transmission.Because electricity is currently so cheap, in commute mode, the cost is about 1/5th that of gasoline. Obviously, at $1/watt for photovoltaics, this might be even cheaper. And because the plan is to have it recharge in about six hours from a 110 VAC outlet, it is a bit more mass market than the Tesla Motors vehicle, which takes either 33 hours to recharge--or a special, 220 volt, 70 amp circuit to recharge in 3.5 hours. Labels: solar power Suppressing Freedom of Speech I mentioned a few days ago the Canadian courts upholding an Alberta Human Rights Commission decision that effectively bans criticism of homosexuality. Here's yet another story, again, from a Christian website, but other than the target of the complaint itself, there seems to be no news coverage of this. TORONTO, December 20, 2007 (LifeSiteNews.com) - In a press release today Catholic Insight magazine responded to the charges in a human rights complaint against it by Edmonton resident Rob Wells. The magazine’s editor, Father Alphonse de Valk, dismisses the complaint as unfounded and says he intends to contest it vigorously. Fr. de Valk says the magazine considers all of the actions against it to be "trumped up and made with the intent to harass".Can you imagine if homosexual advocacy groups had been subject to this kind of harassment in the 1960s for simply advocating their position that people should be free to have sex with members of the same sex? I don't know what it costs to defend yourself from the Human Rights Commission, but I can't imagine that's it $9.99. There comes a certain point where the cost of defending yourself has a severely chilling effect on freedom of speech. Freedom of speech, homosexuality widely accepted: pick one. Labels: freedom of speech, homosexuality Thursday, December 20, 2007
I Do NOT Want To Give Up My Corvette But it isn't looking good. My rationale for maybe buying a beater 4WD was, "They keep state highway 55 pretty well cleared--I only need to get back and forth to the Old Highway." But last night, I was following a snowplow, and this weird slushy snow was falling at the summit--and I could only go about 5 mph. If I turned off traction control, I could get a little more speed, but it was mostly going sideways, which is not particularly useful. I had to park on the shoulder--it wasn't going anywhere. I drove a Subaru Impreza today--the stripper model sedan. I was really impressed--very, very nimble handling, and I could definitely feel the benefits of all wheel drive as I was cornering. It is obviously not going to have the cornering capabilities of the Corvette, but it was surprisingly fun to drive because of the crispness of the steering. I would prefer a station wagon, but the salesman told me that there was no Impreza wagon--you had to move up to the pricier models to get a station wagon. I am going to assume that because he was new there, that he didn't know that there is an Impreza wagon. I can see that the dealer actually has one in inventory, so it couldn't be, "We don't have it so it doesn't exist." I also drove a 2002 Subaru Outback with 36,000 miles--which they were asking only a few hundred dollars less for it than the new 2008 Impreza. Yes, it was more spacious, but it didn't feel as nimble--and for a used car out of warranty, that's pretty silly. I suppose that I should drive the Suzuki SX4 Crossover, and maybe the Suzuki Aerio AWD as well. I really, really don't want to give up the Corvette, but it is increasingly apparent that I need something for December through mid-March. The ideal would be if there was someone with a new 4WD who lived in Boise, and was willing to swap it for the Corvette during the winter. But even Boise in winter isn't exactly optimum Corvette driving conditions. Homelessness, Mental Illness, & Medical Costs Interesting article in the December 18, 2007 San Francisco Chronicle about the high costs that homeless mentally ill persons impose on San Francisco: Niels Tangherlini is willing to state the hard truths about San Francisco's street population. And he's doing it, even if it causes howls of protests from advocates for homeless people or from some city political leaders.Here's some painful truths from those on the front line. Mental illness and substance abuse are strongly correlated, because people with serious mental illness often intoxicate as a form of self-medication. It is often only a short-term solution, and many of the common intoxicants lead to other serious problems, as this article points out. The inability to admit that mental illness is a major part of what causes homelessness in San Francisco (and a lot of other big cities around the country) means that the leftist screeching about "housing" ends up obscuring that for many of the homeless, having housing only solves one small part of the problem--and then, only as long as they can manage a place of their own. The pleasant little theory about deinstitutionalization was that the severely mentally ill would end up back in their communities, receiving community-based psychiatric treatment. It didn't happen, because many of the mentally ill are not sufficiently well--or at least, not consistently so--to hunt up all the social services that they need to keep from freezing to death, or dying of pneumonia, or getting murdered by either other mentally ill homeless people, or common thugs looking for a thrill. As much as the mental hospitals of the 1950s were denigrated as horrible institutions, they at least simplified the providing of basic services to many of the most seriously disturbed parts of our society. What we are doing today in places like San Francisco is not only cost inefficient, it is profoundly inhumane. Labels: deinstitutionalization Wednesday, December 19, 2007
The Alternative to Solar Panels For Backwoodsmen This is one of those news stories that I don't know whether to laugh or cry: Toshiba has developed a new class of micro size Nuclear Reactors that is designed to power individual apartment buildings or city blocks. The new reactor, which is only 20 feet by 6 feet, could change everything for small remote communities, small businesses or even a group of neighbors who are fed up with the power companies and want more control over their energy needs.I'm a supporter of nuclear power. It isn't as dangerous as the lunatic fringe of the environmental movement would like you to believe. But I do cringe a little bit at nuclear power reactors aimed at a market that hasn't quite mastered the art of setting their VCRs to record programs at a particular time. Homelessness in Boise Idaho Values Alliance isn't happy about a Boise City Council decision: The city of Boise last night set aside $2 million in surplus funds (read “overtaxation”) to implement a 10 year plan to deal with homelessness. On the grounds that you always get more of what you subsidize, expect Boise’s homeless problem to be worse, not better, a decade from now.The December 19, 2007 Idaho Statesman reports: The Boise City Council spent $2 million Tuesday to ease homelessness in the city.Now, I can agree that if the money isn't spent sensibly to deal with the root causes of homelessness, there is a real risk that increased funding to help the homeless might increase the number of homeless in Boise. But there's nothing improper or immoral about trying to alleviate suffering. It may be ineffective, if the city spends that money on measures that only alleviate the suffering of the homeless one night at a time. But at least this news account doesn't indicate that is the plan. It may well be that the social programs that they intend won't solve the problem. A significant fraction (although not a majority) of the homeless in Idaho are in that state because of mental illness. There's not much that Boise can do to solve that problem. It will require the state to take steps to correct our current system of institutionalization. A large fraction of the homeless in Boise, from what I can find out from talking to people who have worked at the Boise Rescue Mission, are there because of alcohol and drug abuse problems. There are people whose drinking, meth, marijuana, and other drug problems take precedence over having a place to live. These are tragedies, but I am unclear what social programs are going to fix this. There are children who are homeless because Dad disappeared, or is in prison, and Mom has no job skills, or has a substance abuse problem of her own. There is some hope that some of the social programs that Boise wants to spend that money on will be helpful. Of course, teaching young people to make moral and responsible decisions about sex, children, and marriage would help as well, but obviously, Boise isn't going to be doing anything like that. (The ACLU would doubtless file suit to prohibit anything that even slightly smacks of religion or self-restraint with respect to sex.) We can argue about whether particular policies are pragmatically effective, and at what point governmental assistance crosses the line from "necessary for their support" to "you don't really need this." But in a place like Boise, where it drops below freezing part of the year--and darn cold for several more months--no one should be required to sleep in a refrigerator box, under a bridge, or in a car. We can argue about whether government is the most effective mechanism for providing assistance. In small towns, such as Horseshoe Bend, it appears that voluntarism is alive and well, and working well. In big cities, it is often a different situation, and as much as I would prefer the government not be in the charity business, it may be necessary. Why? Because there are a lot of people who take advantage of the diffuse nature of private charities, moving from one to another to get what they can, rather than confront substance abuse and laziness problems. Let me close with one very important point: America was originally thought of as a Christian commonwealth. As I pointed out a while back, Blackstone's Commentaries on the Laws of England recognized that while the law did not require equality, there was an obligation of the community to provide at least the necessities of life (which would include medical care): THE law not only regards life and member, and protects every man in the enjoyment of them, but also furnishes him with every thing necessary for their support. For there is no man so indigent or wretched, but he may demand a supply sufficient for all the necessities of life, from the more opulent part of the community, by means of the several statutes enacted for the relief of the poor, of which in their proper places.There are certain moral obligations of a Christian commonwealth, and Blackstone captured it well. Liberals will doubtless be cheering about this--while ignoring the rest of the moral obligations that go with it. There are a great many social problems that we are facing today that are the results of liberals refusing to promote or encourage morality. 1. It is not okay to be encouraging the sexualization of children. A 12 year old--or even most 16 year olds--is not capable of making particularly rational decisions about whether to have sex. 2. It is not okay to be encouraging the bearing of children out of wedlock. Marriage isn't a perfect solution to the problems of impoverished single mothers and their children, but it is an improvement over the "Baby Daddy" problem of males (I hesitate to call them "men") who impregnate teenagers and then disappear. 3. It is not okay to tell young people that there is nothing right or wrong--that everything is culturally relative. There are so many pressures encouraging misbehavior even among those who know that they are doing wrong. Telling young people that right and wrong are utterly meaningless terms removes one more restraint on misbehavior that is socially and personally destructive. Does This Mean Edwards is Pro-Life? I mean, if this sleazy story is true, of course. The National Enquirer is among the few newspapers below the New York Times when it comes to credibility with me, and as this article points out, the National Enquirer is owned by a major Clinton backer...but that's probably just a coincidence, of course! Anyway, if Edwards eventually comes clean and admits that he impregnated one of his campaign staffers while courageous Mrs. Edwards has been recovering from cancer, I am sure that his staff will spin this as, "See, John Edwards may believe in a woman's right to choose, but he is personally opposed to abortion!" Or perhaps he is waiting to put the hammer down so that he can demonstrate his commitment to a woman's right to choose, right up to birth! I realize that expecting moral perfection (or even moral adequacy) from elected officials is unrealistic, but it is reasonable to expect enough judgment and good sense to do the following: 1. Stay faithful to your wife at least until after the campaign. 2. Learn the use of condoms. 3. Do not have sex with interns in the Oval Office. 4. Keep your feet and hands entirely within the bathroom stall. Labels: 2008 presidential candidates A New Method For Deciding Tenure? There are a lot of arguments against tenure for professors; I won't go into them here. But this article in the December 19, 2007 Inside Higher Education concerns me, because having failed to win tenure, a gay law professor is now suing on the grounds that members of the tenure committee weren't honest about their reasons: Hammer’s suit is based on contract law, not discrimination law; there are no federal or Michigan laws barring discrimination on the basis of sexual orientation on which he could sue. His suit is based on the idea that he was assured when accepting the job at Michigan (and turning down other offers) of the university’s commitment to equity for gay employees, as outlined in the faculty handbook and various university policies. Hammer’s legal specialties are health policy and Southeast Asia, especially Cambodia. So while he was out to colleagues, his teaching and scholarship did not focus on gay issues.There are at least two major problems with this: 1. People are often members of organizations with whom they do not completely agree. 2. Some of those who voted against Hammer's tenure might well disapprove of homosexuality, and yet made their decision based on the quality of Hammer's scholarly work. In practice, if Hammer gets his way, universities will find themselves pressured to remove anyone from tenure committee decisions who is a member of a church that disapproves of homosexuality--which in practice means that the tiny number of Christians, Orthodox Jews, and Muslims that are on faculty will be further marginalized. Can you imagine the uproar if a conservative denied tenure (which I would presume is extremely common) demanded that members of the tenure committee be carefully examined about their political beliefs, with the assumption that their decision was based on lies? Labels: academic integrity Tuesday, December 18, 2007
Gangs and Child Sexual Abuse Michael Williams points to this disturbing statement in a disturbing article about Los Angeles street gangs in the December 12, 2007 LA Weekly: Sherills told me he became a gangbanger because he was sexually molested. “But that’s taboo,” he said. “You don’t say that. Feeling worthless, like you are an object. In this neighborhood 90 percent of young men have been sexually abused. I will say 99 percent of ladies. Everybody is operating within the cloud. It’s the elephant that is sitting in the room that no one speaks of.”I wouldn't take those numbers as meaning anything more than Sherills' statement that sexual abuse of children is not just the norm, but extremely common. I can remember reading a collection of surveys done in the 1970s, and while the percentage of adults reporting sexual abuse as children was much higher than anyone had expected, one survey done of females in South Central Los Angeles was extraordinary--half reported being sexually abused. One of the shocking discoveries of the 1980s was not just how common sexual abuse of children was, but that it wasn't just in ghettos. I can remember how amazed a lot of people were when magazine and newspaper articles first started reporting that this was surprisingly common in middle class suburbs in Silicon Valley. These days, there is a tendency to overemphasize its ubiquitousness across all classes--perhaps in overreaction to the former tendency to assume that this was almost entirely a ghetto behavior. Labels: child sexual abuse Monday, December 17, 2007
Not Your Ordinary Gift Catalog One of the catalogs that we use every year around this time is a bit different. It's the World Vision Gift Catalog. No, you won't find any iPods in it, or notebook computers. But here's a sample of the kind of stuff that you can buy for someone you don't know: Deep Well for Disease-Free WaterOkay, maybe you don't have $18,000 sitting around for charitable contributions, but smaller donations can add up, and there are a lot of other very worthwhile projects that you can help fund. Tubes? Tubes? We Don't Need No Stinkin' Tubes! With apologies to The Treasure of Sierra Madre. The more I have been looking at the problem of how to reduce the weight of the tubes that carry the mirror and mirror cell on one end, and the diagonal mirror holder and eyepiece focuser on the other end, I find myself wandering back to my original concept--totally tubeless. The original brilliant (or deranged) scheme was three square tubes to which the mirror cell will attach at one end. This has never been the big problem; there's three bolts to hold the mirror cell to the square tubes that provide the necessary stiffness. At the other end, I have to attach a eyepiece focuser, a diagonal holder to position the secondary mirror in place, and a finder scope. But without a tube, how do I attach those items?  The green squares are the 1" (or perhaps less) tubes that provide the rigidity. With a three vane spider, the spider "legs" attach directly to the tubes. These have to be very rigid; probably steel, not aluminum, since you want them as thin as possible to reduce diffraction. But how do you attach the eyepiece focuser? With a piece of aluminum, probably 1/8" thick or more that forms half a hexagon, bolted to the square tubes at the 120 and 240 degree angles (where 0 degrees is the tube at the bottom). The finderscope can bolt directly to one of the square tubes. This approach knocks eight to twelve pounds off the total weight, and even better, knocks that weight off the ends of the scope--where they produce the maximum load on the square tubes. Even if I have to increase the thickness of the tubes somewhat, and even if the increase in the weight of the square tubes were to cancel out the weight savings from the round tubes, this means no money having the round tubes made, and no struggles finding a vendor to make them. The downside is that the diagonal spider legs have to be stronger than before, since they are providing some structural reinforcement at the far end. Alternatively, since I am already putting a shelf in place for the eyepiece focuser to mount, I could just complete this all the way around at both ends. I also have to come up with some way to cover the optics when not in use. I also have to completely wrap the telescope in black cloth when in use, but I was already expecting to have to do that. Labels: machining, telescopes Aluminum Tube Vendor Needed The people that I was planning to use are concerned that they won't be able to weld an aluminum tube that is perfectly round--as much as 1/4" out of round. Since they can only make tubes in 1/4" increments, this means that I have to go to a 20.75" outside diameter tube to get what I want. Maybe the problem is that they don't have a mandrel the right diameter to wrap the aluminum around when they weld it. Any suggestions? The people that did the plates for the mirror cell are high on my list, since they did a good job and fast. Any other suggestions? UPDATE: More details, in case you run a welding shop! 20.40" ID +- .005", .090" wall, 8.00 +- .05" length. It can be roll formed. Cheap is important; an extrusion is unnecessary expense. Grind marks on the weld are just fine; I will polish and paint it myself. I could consider somewhat thicker tubing, but even going to .125" wall increases the weight from 4.52 to 6.28 pounds. I'm reluctant to go thinner out of concern about deformation. One of the tubes is going to carry 30 pounds, supported by three screws, although that weight is such a close fit that it will strengthen the tube (at least in that section); the other tube will carry less than ten pounds. UPDATE 2: At least one vendor says that .090" wall aluminum tubing won't be stiff enough for my purposes. And yes, he is out of .090" anyway at the moment; wouldn't I like it made of .125" instead? There's obviously a formula for computing how much a tube deforms under load, depending on thickness and Young's modulus. My guess is that the formula is pretty much the same as a solid rectangle. Right or wrong? I have an intuitive sense that because the top half of a tube is essentially an arch, which handles load far better than a flat surface (hence, the importance of the arch to creating Roman architecture) that if you use the deformation formula for a plate supported on four sides with a point load that you won't be too far off the same results for a point load at the center top of a tube, since much of the point load would be distributed down through the "arch" into the rest of the tube. If so, a .090" wall tube of the dimensions specified above with a ten pound load (one third of the mirror cell plus mirror weight) would produce a deformation of about .3 mm at the surface. This is acceptable. A .125" wall would knock that deformation down to .1 mm. It's tempting to go for the extra thickness, even though it increases the weight by a bit more than 1 1/2 pounds per tube. Part of what makes the equation so interesting is that most of the weight of the telescope is in the lower part of the tube, where the mirror and mirror cell are located. The upper assembly weighs almost nothing. When computing the deformation of the square tubes on which both assemblies are located, the weight of the lower assembly takes precedence; it is far heavier, and induces far more deformation. I have been working on the assumption that from the balance point of the telescope to the lower end would be 23 inches, but the closer that I get the balance point to the mirror cell assembly, the shorter the distance over which the mirror cell deformation takes place. Reducing the weight in the upper assembly moves the balance point closer to the mirror cell, reducing the deformation in the square tubes, and allowing me to go to smaller, lighter tubes. For example, if I moved the balance point from 23 inches from the mirror end to 15 inches, it reduces the worst deformation from .014" to .0037". At that point, I could consider going to a thinner set of square tubes, reducing the weight a bit more. Labels: machining Sunday, December 16, 2007
Big Bertha Rebuild: Mirror Cell Almost Complete Here you can see it from the side, showing the spring suspension that allows you to collimate the mirror quite precisely to the optical axis of the telescope. Remember that because the collimation screws are 20 threads per inch, one complete rotation of the wing nut moves that screw 50 thousandths of an inch. Applying a little trigonometry to the angle involved shows that you can actually get motions of the mirror's face below a thousandths of an inch, if you make very, very slight movements of the wing nut.  Click to enlarge Here's the back, where the wing nuts do the adjusting. There's only an inch or so of travel, but that's quite sufficient, as long as you aren't grossly mispositioning the mirror cell in the tube.  Click to enlarge What's left? It turns out that the 3/8" long screws for the mirror clips are just a little long. I need to buy some aluminum washers. If I could buy some 1/4" long aluminum screws this size, that would be even better, but there's no local supplier, and buying a box of 100 of them mail order seems a bit excessive. It isn't like the shorter length is going to shave even an ounce off the total weight. I haven't put the furniture glides onto the mirror plate yet. The furniture glides provide both a metal/glass separation, and provide air flow to speed up mirror cooling. Until I paint or have it anodized, there's no point in putting them in place, since they stick to the surface with adhesive. I am ready to verify the dimensions before I order the aluminum tubes in which this, and the diagonal assembly, will fit. Labels: machining, telescopes Why Does Bush Keep Vetoing S-CHIP? Here's his veto message for the second veto. The main points seem to be: 1. The goal should be to move the uninsured to private health insurance, not government health insurance. 2. It covers adults, not just children. 3. It covers Americans with incomes above the median income. 4. "It would still result in government health care for approximately 2 million children who already have private health care coverage." Bush also claims that this second try at S-CHIP was essentially the same as the first one that he vetoed, and that, "The leadership in the Congress has refused to meet with my Administration's representatives." I can't quite tell what the truth of the matter is. I shudder to think of trying to read the bills myself, and make sense of them. When you start reading entitlement program bills, you often I need significant expertise to figure out what the bill actually does--and people who have the expertise, like the Center for Budget Priorities or the Heritage Foundation, often have their own agenda and biases. I do think that politics probably plays a big part in this. According to this December 13, 2007 CNN report: This December 13, 2007 New York Times report also points to political interests in having a fight:
Remember that politicians have an interest in accentuating the differences between the parties. I would not be surprised if some members of Congress passed a bill specifically to have something to use in next year's elections as a differentiator. Bush might well see his sudden willingness to veto an increase in Congressional spending as a way to make voters forget how willing Republicans were to raise spending in the last few years. Labels: health care Big Bertha Rebuild: The Joys of Aluminum Fasteners I mentioned yesterday that I was going to buy some shorter bolts for the mirror cell. When I reached Home Depot, I was overjoyed to discover that they had a number of aluminum machine screws in the sizes that I needed. Reasons for switching from steel to aluminum for the mirror cell fasteners: 1. About 1/3 of the weight. I've knocked three ounces off the mirror cell this way. Final weight is almost certainly going to come in at or below four pounds. 2. If I get the cell anodized, I can get all the fasteners anodized as well. 3. Aluminum to steel interfaces means a bit more risk of corrosion (although Big Bertha is not going to be standing outside in the rain, and this isn't a moist climate). Aluminum to aluminum knocks this out completely. I'm told that using galvanized steel with aluminum helps; no surprise, because aluminum's electronegativity is 1.61, zinc's is 1.65, and iron (primary component of steel) is 1.83. Aluminum and zinc are so similar that their would very, very little electron flow, while aluminum and iron would have a bit more. 4. For certain applications, aluminum's lower tensile strength relative to steel means that I would have to go to much larger bolts. As I mentioned some weeks ago, two 1/4"-20 bolts should be many times more than sufficient to hold Big Bertha to the dovetail plate--but I will probably use four, just to be overcautious. But that's a load of more than 50 pounds. Here, I have a roughly 30 pound load distributed across six 1/4"-20 bolts in the mirror cell, and across three 1/4"-20 bolts holding the mirror cell to the tube. I may end up using galvanized steel bolts to hold the mirror cell to the tube--just to get the advantage of a dramatically higher tensile strength. Labels: machining, telescopes Governor Romney Really Believes This? I've received emails telling me that pro-choice Romney really is following Mormon Church policy--that the Mormon Church opposes abortion, but doesn't believe that it should be illegal. I don't know if this is true or not. I do see this news coverage of how Romney dealt with the question recently, and it just makes me scratch my head: Regarding his flip-flop on abortion rights from the time he was running for office in Massachusetts, Romney said he thinks “almost everyone in this nation” opposes abortion.If he means that "almost everyone in this nation" would prefer that abortion not be necessary, that may be correct. I suspect that the only people who are enthusiastic about abortion are abortion doctors who do it for the money. (I suspect that there are abortion doctors who do it from strongly held beliefs as well--and not primarily for the money.) Pretty clearly, there is a large minority of Americans who believe that there's nothing wrong with abortion--certainly not enough to prohibit it, or even regulate it in a way that discourages it. This poll done a few months back asked how Americans felt about abortion in a number of different situations: the result of rape or incest; fatal birth defect; puts the mother's life at risk. Americans remain strongly supportive of abortion in most cases. This makes the pro-choice position that overturning Roe v. Wade would make abortion broadly illegal pretty silly (although there might be a few states that would regulate abortions much more strictly than today). The highest level of support for making abortion illegal was "If the pregnancy is unwanted" and in that scenario, 39% wanted it still to be legal. I wonder if Romney just didn't explain this well, if he hasn't been talking to people outside his church about abortion, or if he is making a statement that is so absurdly preposterous in the hopes of straddling the fence. Labels: abortion When Engineers Do Theology... The results are often wildly entertaining. Brian Mickelthwait mentions the widespread smuggling of Bibles into China--a nation that is beginning to have a very large Christian population, and the likely long-term impact of that on the political system there. He quotes someone else about the results of 50 million "Bible bombs" on the current thuggish government. Mickelthwait is one of those people that doesn't believe, but recognizes the positive impact that Christianity is likely to have: The more I ponder Christianity, the more (a) I think that most of what it says is barking bonkers, and the more (b) I recognise it to be a profound force in the world, as much because of what it doesn’t do - challenge Caesar on his home turf, basically - as for what it does.One of the comments over there by a Steve Poling is what the title of this posting refers to: Impedance mismatch? What the heck is that? Here's an explanation: The impedance of the load is expressed in ohms, and the relationship between the current and the voltage in the circuit is controlled by the impedances in the circuit. When a signal source, such as our composite video output, sees a very low-impedance circuit, it produces a larger than intended current; when it sees a very high-impedance circuit, it produces a smaller than intended current. These mismatched impedances redistribute the power in the circuit so that less of it is delivered to the load than the circuit was designed for--because the nature of the circuit is that it can't simply readjust the voltage to deliver the same power regardless of the rate of current flow.I don't think that any theologian or pastor would use the analogy of "impedance mismatch" to describe the gap between the wisdom of God and the wisdom of men. One gratifying aspect of the comments over there is how civil they are. A few Christians took exception to Mickelthwait's statement about our faith being "barking bonkers," but more typical were thoughtful and friendly discussions of the gap between faith and reason: Christianity is bonkers by design, if you define bonkers as irrational. Paul noted “The man without the Spirit does not accept the things that come from the Spirit of God, for they are foolishness to him, and he cannot understand them, because they are spiritually discerned.” (1 Corinthians 2:14). But then, I’m a mystic, and view rationalism as one tool, not the only tool we have.And another commenter's single word response to the description of Christianity as "barking bonkers": Woof!As one commenter observed: I don’t seem to see anyone in these comments calling for Brian M. to have his head cut off with a dull knife. That is opposed to another prominent religious belief group that thinks anyone insulting their beliefs should be removed from the living. Big Bertha Rebuild: Mirror Cell Continued I made a bit more progress today. The base plate now has the flanges attached:  Click to enlarge The mirror plate now has the "corral" pieces in place. These I made by rather the same method as the flange brackets, except that unlike the flange brackets which bolt to the top of the base plate, these are bolted to the underside of the mirror plate.  Click to enlarge Here you can see how the mirror clips attach to the corral brackets.  Click to enlarge Because this is only a 1.5" thick mirror, I was originally planning to make these mirror clips quite short--but then it occurred to me that if at some later time I wanted to use a higher quality 17.5" mirror--one that was a bit thicker--better to have enough room. The mirror clips are held in place by 1/4"-20 screws into the threaded hole in the corral brackets. I made a tight enough fit that once the mirror is in the corral brackets, they are effectively a spring fit. Of course, if the telescope ever gets upside down, it would be a very good thing to have something more than a spring fit holding that mirror in place! So I will go ahead and complete the mirror clips. I still need some more parts, which I expect to pick up tomorrow to put this all together. I need some 1/4" long 1/4"-20 bolts for the mirror clips (since they are holding two 1/8" thick pieces of aluminum together, and the extra length would run into the mirror), and some 1/2" long bolts to replace the existing 3/4" 1/4"-20 bolts that hold the flanges and corral brackets in place. It looks a little ugly to have the extra 1/4" of bolt sticking out, and it adds weight that I don't really want. I need some 2" long 1/4"-20 bolts for the collimation adjustments. I already have the springs (which you can see in the picture above) that I salvaged from the existing monstrosity. Because of some compromises that I had made to keep using the existing tube and back door assembly, the current adjustment screws are 4" long--simply too big. I also need some of the furniture pads that I use to lift the mirror off of a direct glass to metal contact (especially of concern where they will be touching the bolts that hold the corral brackets in place). The good news is that the total weight of the current mirror cell components is still only four pounds! I still have to add the 2" long collimation bolts, and the furniture pads, but I also get to knock perhaps an ounce or two off by replacing 12 of the 3/4" long bolts with 1/2" long bolts. I am quite confident that this will still be a 4 1/2 pound mirror cell--or about 1/4th the weight of the only commercial one this size that I could find. And I still have complete confidence in the stiffness of this cell! Materials cost so far is about $150--or about 40% of the cost of the commercial mirror cell for this size. Labels: machining, telescopes |
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