Sunday, June 17, 2018

Followup on Flywheels and Drilling and Tapping

Reference here, and comments on how to drill and tap the 8-32 holes that are 10 degrees from vertical.  To begin with, the easy part was getting the angle.  I have an adjustable angle plate from my Sherline tools that I could incline at the 10 degree angle and then clamp the flywheel to the table with the Sherline clamps.  This is where having been playing with the Sherlines since 2003 is really helpful. 

Actually drilling and tapping at the 10 degree angle turned into a job where none of the tools I have would work.  I wanted to use the big mill as a precision drill press (it's really good at that), but its drill chuck is so wide in diameter that it can't get close enough to the hub to use a center drill to give the bit a good start, and since the the surface is both inclined and round, the drill bit won't start by itself.  Time to use my tools to make tools - a recurring theme. 

I ended up trying two approaches that didn't really work, before settling on one that worked fine.  This picture shows the first two.  The very first is the bottom one.

The bottom piece is a quarter inch diameter brass rod, drilled out with the drill bit recommended for 8-32 threads (#29 - conveniently shown in the right end of the top rod), then drilled perpendicular to its axis (near the right end) with that bit and tapped for one of those 8-32 setscrews.  The problem was that there wasn't enough meat in that brass for more than about 2 threads, and they stripped out when I tightened the setscrew.

Onto rev 2, the top one.  The top holder is 3/8" aluminum, drilled with same drill bit.  Now that there's more metal, it grabs the bit securely and doesn't rip out.  This is when I realized I had to use the center drill, and repeated the drill along the bore (3/16") and drill/tap for the setscrew.  Which is when I realized this approach was screwed.  The tool holder holding the drill bit cleared the flywheel, but the center drill is much shorter and the setscrew wouldn't clear it. 

Time for rev 3 of the holders.  Go back to quarter inch brass and soft solder (tin-lead electronics solder) the bits into the holder. 

Back when I was in the biz, if someone showed me that soldering job (top) I would have told them, "it looks like a solder-eating bird took a shit on it", but holding a file against it while it was rotating in the spindle cleaned it up and made it look pretty.  To me, the important part was that I could do it with my Metcal soldering iron rather than a torch.  I doubt the Metcal got it hot enough to damage the temper, while a torch might have.  

You'll notice the drill bit is not soldered in.  I pressed that in by using my drill chuck in the lathe tailstock as a ram and putting a piece of scrap between the bit and and the lathe chuck.  Then I tried to remove it, even using big pliers on both the brass rod and the drill bit.  No luck.  I test drilled a piece of scrap aluminum with it and the bit didn't move.  Then I sharpened the bit to add whatever advantage I can get. 

All of the tool holder work was done on my manual Sherline lathe.  They're all small work pieces, and I don't need horsepower, I need precision.

Now it was time to set up for the drilling, which I did on the big mill using my Rumblepad hand controller to position everything properly before drilling.  I let the brass rod holding the center drill clear the most protruding edge of the flywheel by 0.020".  I found I didn't get a good picture of the angle plate, but grabbed a couple after the main work was done.  I stopped during tapping to grab this shot which kinda shows the overall setup. 

In this picture, the metal bit hanging down at top center is countersink cutter; it's held in the same 1/4" collet that held the tools and is just there to match a divot in the top of the tap wrench.  It helps ensure that the tap stays vertical (although it doesn't look that way in the picture).   As I advance the tap, one half rotation of the wrench at a time, I lower the countersink. 

Yet another example of how a task that should be a simple operation turns into something quite a bit more involved.  I should have realized that a quarter inch long set screw would interfere with things and not bothered with the first attempts, but I rushed in rather than spending more time visualizing what was going to happen.  This is straightforward geometry/trigonometry and I could have anticipated all these issues better.  

Now it's on to the next part, the bracket that holds this flywheel.  I'm going to redesign that to use ball bearings, rather than use Duclos' approach of letting a steel shaft rotate on aluminum. 

Saturday, June 16, 2018

RIP Matt "Guitar" Murphy

I was saddened to get an email from a friend saying that Matt "Guitar" Murphy passed away Friday.  He was 88.  Most people will probably know Matt from the 1980 comedy "The Blues Brothers".
Murphy's death was first announced in by his nephew Floyd Murphy Jr, who performed alongside his uncle. "He was a strong man that lived a long long fruitful life that poured his heart out in every guitar solo he took," Floyd Jr. wrote of Matt Murphy in a Facebook post (via Deadline). No cause of death was provided. In 2002, Murphy suffered a stroke that forced the guitarist into semi-retirement.
There are no details on the effects of that stroke, but I presume it hindered his ability to play, which would have been sixteen years of living in hell for a musician like Matt Murphy.   Murphy was probably hired for the Dan Ackroyd and John Belushi movie as a well known musician they had heard.  Rolling Stone says he was a product of the legendary Chicago blues scene of the Forties and Fifties, and had worked alongside artists ranging from Ike Turner (as members of Junior Parker's Blue Flames) and Etta James to blues musicians like James Cotton, Willie Dixon and Sonny Boy Williamson. 

One of the most popular scenes in the movie depicts Matt as husband to Aretha Franklin in small restaurant in Chicago.

Blues music has brought me tons of joy over the years.  RIP Matt, we loved your work. Some good old videos at the Rolling Stone link.

Friday, June 15, 2018

If You've Worked for a Big Company You'll Understand This

Given the FBI Inspector General's report detailing the horrific ethical issues at the top of the agency in DC, Director Christopher Wray said all the lower level employees will be sent for training
The FBI will make its employees undergo bias training, Director Christopher A. Wray promised Thursday, after a devastating report found the bureau made bad decisions, has a culture of leaking sensitive information, and may have skewed campaign-season decisions because of bias.
If you've worked for a Fortune 500 company, or probably any company with more than something like 100 employees this is a familiar script.  Business as usual.  One of the executives on Mahogany Row does something wrong, so for the rest of time the rank and file workers get penalized.  Like when company officials from some place were accused of "insider trading" and as a result, every employee in the big companies has to take a mandatory insider training class every year.  In perpetuity.  Or when someone decided that a CEO being optimistic about the company wasn't to encourage the group to but was a dishonest ploy to swindle investors, so Congress passed the Sarbanes Oxley act, and now every employee at a publicly traded company has to take an annual SOX class. 

Here, the top layer of officers in the FBI were as biased as a skunk's spray is stenchy, so the rank and file agents will get training in being objective while - from all we can see now - none of the actual offenders will suffer any consequence whatsoever. 

Buck Sexton, talk radio guy and expert on the talking head circuit due to being an ex-Three Letter Agency guy, sums it up nicely on Twitter (via Twitchy): 

The IG report itself reminds me of the Comey press conference on Hillary from July of '16.  That time out of 15 minutes of air time, he spent 13 of them listing every federal felony and other crime that Hillary committed.  Then he spent the last 90 seconds explaining he was going to do nothing, turned and walked off stage without taking questions or interacting at all.  In this case, the IG points out example after example of all the wrong things the FBI did that were biased and/or illegal, but then said there was no evidence of bias.  Again, these were the headquarters staffers, including the Weasel Comey, Andrew McCabe, Peter Strzok and Lisa Page.

People have been saying for a while that this might well be the biggest political scandal in our country's history.  To have what's supposed to be the premier law enforcement agency in the country apparently trying to take out the lawfully elected president is just so wrong it's hard to wrap my head around it. 

Thursday, June 14, 2018

Family Portrait -- Sort Of

I spent the last couple of afternoons making the next part for my flame eater engine, the flywheel.  Here I pose big brother flywheel along with the smaller version that you've seen before, if you're a long time reader. 

The big brother is 3-3/8" diameter and the holes are 3/4" diameter.  Little brother is 2-1/2" diameter and the holes are 1/2".   Little brother is actually a bit more complex because the hub is threaded 1/4-28 for about a third of its length and reamed to 1/4" on the rest while big brother is reamed 1/4" the whole way.

Actually, this is my "done with the flywheel picture", but I realized I'm not really done.  I realized that I haven't drilled and tapped the set screw holes in the hub.  That will involve a setup that'll be a new technique for me, clamping the wheel to vertical surface with a spacer at the bottom to introduce that ~10 degree angle.


Wednesday, June 13, 2018

Improving the Performance, Reliability and Cost of Fuel Cells

I was mildly surprised to find the most recent thing I'd written on fuel cell cars was back at the very end of 2015.  That piece was based on a Design News post that said for fuel cell vehicles to be successful, fuel cell costs have to come down.  I'm interested in the technology, and I think someone should be researching them, I just don't think it's the federal governments place to use tax money for this research.

This is the province of fundamental engineering research in universities, probably funded by companies with interest in commercializing the technology.  Power Electronics magazine runs a piece on some of the work this week.
To meet this need, R&D at several U.S. universities and national laboratories is focused on making fuel cells a more widely used energy source. Some of this R&D is in the basic research phase, some is more advanced. This R&D is complex because it combines chemical and electrical disciplines, so it needs scientists with an understanding of both. And, sometimes it is hard to find people with this inter-disciplinary background.
First stop is the University of Delaware’s Center for Fuel Cell Research (CFCR), a resource for innovative energy technologies under the umbrella of the University of Delaware Energy Institute (UDEI).
Ajay Prasad, director of the CFCR, says, “Hydrogen-powered polymer electrolyte membrane fuel cells have already demonstrated the potential to replace internal combustion engines in vehicles and to provide power in stationary and portable applications.” He notes that a major challenge to commercialization of this technology is the durability of the membrane, which is typically made from a polymer called Nafion. During fuel-cell operation, the membrane undergoes chemical and mechanical degradation, leading to cracks and pinholes that shorten its life.
Prasad and two colleagues from the UD Department of Mechanical Engineering, Liang Wang and Suresh Advani, have developed a self-healing membrane incorporating microcapsules prefilled with a Nafion solution. A patent application has also been filed. “The microcapsules are designed to rupture when they encounter defects in the membrane and then release the prefilled Nafion solution to heal the defects in place,” Liang Wang explains.
Lian Wang with a sample of their enhanced polymer.  Power Electronics photo. 

Test results have shown the newly invented membrane with the self-healing property could greatly extend its useful life.  A prototype fuel cell system using this technology is currently being tested in an all electric bus, run by the University of Delaware.  It's not a typical fuel use, as far as I know: the bus runs on a 300V NiCd battery pack, and the fuel cell provides recharging for those batteries, making the fuel cell system a range extender.  The fuel cell, by the way, runs on 16kg (7.3 lbs.) of hydrogen stored at 5000 psi.  That piece I linked to on fuel cell cars talked about 11 lbs. of Hydrogen in 10,000 psi tanks in a Toyota electric car. 10,000 PSI anything sounds scary to me.

Next stop is Georgia Tech Research Institute’s (GTRI) Center for Innovative Fuel Cell and Battery Technologies, where researchers believe that understanding how and why fuel cells fail is the key to both reducing cost and improving durability.
Center director Tom Fuller has been trying to solve what he deems the top three durability problems since he joined GTRI from United Technologies in 2004. “My philosophy is that if we can really understand the fundamentals of these failure mechanisms, then we can use that information to guide the development of new materials or we can develop system approaches to mitigate these failures,” said Fuller, who is also a professor in Georgia Tech’s School of Chemical & Biomolecular Engineering (ChBE).

One of the problems Fuller is addressing includes the chemical attack of the membrane. In a typical fuel cell, hydrogen is delivered to the anode side of the cell that contains a catalyst, such as platinum. The platinum splits the hydrogen molecules (H2) into hydrogen ions and electrons. On the cathode side of the fuel cell, an oxidant such as a stream of oxygen or air is delivered.

With a proton exchange membrane in the middle, only hydrogen ions can travel through the membrane to the cathode. Electrons travel on a different path through the electrical circuit to the cathode, creating an electrical current. At the cathode, the hydrogen ions combine with oxygen and the electrons that took the longer path to form water, which flows out of the cell.
In an interesting comparison to the University of Delaware research, GTRI researchers also find that damage to the membrane in the fuel cell is a root cause problem they're fighting. 
Fuller’s research shows that the membrane, commonly made of a synthetic polymer, is prone to attack by free radicals that create holes in the barrier. The free radicals are formed by the decomposition of hydrogen peroxide (H2O2), a strong oxidizing chemical that can form near the membrane. Perhaps the work done at the University of Delaware can solve this problem.
There's more in the article at Power Electronics, but I think I've hit the most interesting parts. They write about involvement of the Department of Energy's Oak Ridge National Labs (ORNL) in Tennessee and tests at the The National Renewable Energy Laboratory (NREL). 

It sounds to me like basic research, with small scale testing going on, and therefore a couple of years before fuel cell makers can tell if this is progress or not.  There's nothing in the article about the costs of these cells, which seems to go with the immaturity of the technology. 

At this point, there's nothing to lead to a solid prediction of costs reaching "commodity level", not the current astronomical costs that lead to the automakers being unable to profit on a fuel cell electric vehicle even including the Federal subsidies they get. 
Honda Clarity, fuel cell powered EV.  It appears these can be bought now in limited areas, but there isn't much hydrogen infrastructure around, either. 

Tuesday, June 12, 2018

Some Trump/Kim Comments - Because Why Not?

The 24 hour news cycle was predictably all abuzz about the summit between President Trump and First Secretary of the Party Kim Jong-Un.  Last night, I watched Fox's Chris Wallace talking about how nothing has been achieved yet and Kim hasn't given up anything.  I almost yelled at the TV that he was a waste of valuable air time: the meeting hadn't even started yet, of course nothing had been accomplished.  What are you gonna say next, Chris, "water is wet"?

I don't want to talk about what they're saying.  This is just an "as I see it" hodgepodge of thoughts.

To begin with, it's widely known that Kim Jong-Un attended school in Europe.  It's widely reported that one of the ways the people are repressed is by ensuring they don't know how badly they have it.  The people are told they live in a near paradise.  Unlike the vast majority of his subjects, he knows that's a lie; he knows the kingdom is a wreck and he knows he presides over a human rights disaster.  It's also widely reported he really likes much about the US and western cultures.  He loves NBA basketball - hence the peculiar role of Dennis Rodman in the story.  He loves American action movies. 

Someone in the White House, or somewhere else along the line of involved people, got the idea to make a movie trailer to show Kim as the summit opened.  It's an unabashed attempt to show Kim that if he plays nice, he can have personal longevity, wealth, and be recognized as world leader.  It's full of scenes that seem to have been chosen because someone thought he'd like them.  Perhaps you've seen a clip.  That's all I had seen until doing some research here online.  Here is the full, HD version of the video.

Blogger LL over at Virtual Mirage (you are reading him, right?) had some important insights into the chances of getting something through even with a signed document from the summit.  The North Korean economy, such as it is, is largely involved in their military and weapons research.
The North Korean economy is a dependent of the armed forces and the arms industry. North Korea has a mostly closed society and economy that supports and sustains a million able-bodied men in uniform from a population that the CIA World Factbook estimates is 25 million. Four percent of the population is on active duty in uniform. In the US and China, people in uniform account for less than a percent of the total population.
The military reserves and red guards represent at least 20 percent of the population. Adding in family dependents and connections, we estimate that at least a third, and probably closer to half, of all North Koreans depend on the armed forces and the arms export industry as consumers. 
The economic ripple effects of supporting the army, the reserves and the red guards affect every sector of economic activity and almost every household. Without the Korean People’s Army, the North Korean economy would collapse. Without an identifiable enemy (the USA), there is scant need for 50% of a nation to be TOTALLY dependent on the military for sustenance.
As I said in a comment there, I had never considered the terms "military industrial complex" and "North Korea" in the same sentence, but having 50% of the economy dependent on the military could conceivably be a big problem.  It's important to note, as LL does, that South Korea also spends a large part of its budget on the military.
Millions of livelihoods on both sides of the Military Demarcation Line are tied to maintaining the existing conditions of no war and no peace for the past 65 years. Those conditions are so deeply rooted that change itself has become a threat and a huge challenge.
Of the two Koreas, I think the South Koreans could handle workers coming out of the defense sector much easier and an order of magnitude or two faster than the North Koreans.  

In the history of the world, as far as I can tell, one constant of societies has been palace intrigue; someone plotting to off the guy in the throne to take it themselves.  Isn't there a favorite fantasy TV series about this?  Stories are starting to circulate that Kim has replaced "hard liners" in his government with others more open to, if I can reuse the old term from the Reagan era, dĂ©tente.  Depending on how many "hard liners" there are and how well they are hidden in the palace, it's worth asking if Kim can survive.  We know he has no reluctance to kill those he considers a threat, extending to their entire family, so his ruthless brutality may work out to be something that raises his chance of survival. 

Another "information-free" sound bite (in the sense that you already know it) is that "this is just a first step; step one of hundreds to follow".  Among the most important steps are (1) keeping Kim alive - if he's really committed to this, (2) figuring out ways to get the North Korean economy to survive the economic shock.  The real problem here is the double burden of not just having an 18th century economy, but having it organized as a communist economy. 

Monday, June 11, 2018

Confidential to the SAF: Fire Your Ad Agency!!

Let me start here:  I really respect the Second Amendment Foundation.  I know I've donated to them in the past.

Since the crap of the last months, the abandonment of Florida gun owners by the GOP establishment (the Truly Stupid Party) and the rest, I've been thinking about new groups to support.  On the face of it, the SAF has a good pedigree.  The SAF, after all, is the organization that took McDonald v. City of Chicago to the Supreme Court and won (pdf warning).  All together, the SAF has been involved in more important progress and legal victories for the pre-freedom side than any other group I know of.  More here.  It's important to know, the SAF isn't perfect either. 

The thing that bothers me is that every time I'm ready to push the button or write the check, I get some horrible click-bait style, snail mail solicitation from them.

They write like they're trying to attract the absolute lowest IQ voters.  Today I get one that is made up to look like it's some sort of jury-duty related thing.  Seriously.  In big bold letters it says, "Official Jury Ballot Enclosed"; then it's emblazoned with something similar to crap you get on the junkiest of junk mail; it reads like a warning to the postal service.  Rather than describe it, let me show it to you.

Does anybody associate anything but low-budget, bulk-rate junk mail with that?

The inside is just as bad, with single sheet made up to look like a legal draft except for the large bold font at the top declaring it a "Juror Ballot".   It's a "survey" set up to get you mad at the Brady Bunch, Bloomberg, Schumer, Feinstein, Pelosi, and the usual cast of villains so that you'll send in a check.

Again: does anybody take this kind of stuff seriously? 

I can't tell you how many times I put aside an envelope with some low-brow marketing scam in it from the SAF and thought that maybe I'd be less annoyed with them later, but never got past it.  After all, when we respond to this crap, we're rewarding them for it.

Yo, Counselor Gottlieb: talk to us like we didn't just crawl out from under a rock.  Your ads come across as thinking less of gun owners than Bloomberg, Brady, or any of those parties that you list think of us. 

Maybe it's worse than I thought.  According to the Wikipedia, Allan Gottlieb might be the owner of the company that's doing this atrocious advertising.
Gottlieb owns Merril Mail Marketing, Inc., a for-profit corporation, that is his direct response mail fund-raising business.
Gosh, if he owns a "direct response mail fund-raising business" I'll bet chances are pretty good that's the business that's the ad agency I'm asking him to fire.  Yeah, I know enough about business that it's easy to think a guy who owns all the businesses he does isn't familiar with this level of detail of the various operations.  

Saturday, June 9, 2018

Remind Me Not to Go to Kansas City

Busy day, so a saved funny.

Just one letter away from being a typical tourism board sign.

Friday, June 8, 2018

Bernie Sanders' War on Reality

That's not really the title PJ Media used; they said Bernie Sanders Declares War on Disney Over the Minimum Wage, I'm just going with the shorter, more pithy version.
On Saturday, Sen. Bernie Sanders (I-Vt.) declared war on Mickey Mouse. The self-declared socialist launched an assault on Disney for not paying its workers enough, just as minimum wage increases have hurt local economies and Sanders' own liberal state of Vermont has worse inequality problems than Disney.

"We need to shame Disney," Sanders declared at a rally in Anaheim, Calif. "I want to hear the moral defense of a company that makes $9 billion in profits, $400 million for their CEOs and have a 30-year worker going hungry."
You can tell this is either preparation for a 2020 primary run or simply dementia because Sanders is also lying about Disney's union contracts. Disney has already promised to increase wages for Disneyland workers to $15 per hour in under two years - by 2020.  Amid ongoing union negotiations, Disney offered an immediate pay increase to entry-level employees to $13.25 per hour, up from $11 currently.

Over five years ago, I wrote that I'm so tired of this issue that it's hard to even write about it, and I'd already written several pages on it by then, the third year of this blog.  In essence, those of us who oppose federal wage control like minimum wage laws always predict that it's not actually going to help people.  The laws are passed, the predicted bad things happen, and the answer is always to raise the minimum wage higher. 
I'm tired of arguing over this issue because, to be honest, I'm always right and I always lose.  I'm right because I say it will cost the jobs of the people it's trying to protect and it will lead to inflation.  Those things then happen.  And I always lose because not enough politicians have the guts to stand against a minimum wage increase. 
Which is why I say it's declaring war on reality.  Sanders argument, and the argument of all income redistributors, is that the company is making a profit so therefore they should be paying their workers more.  Disney, though, is a publicly traded company (DIS) and they are legally obligated to work for the financial interests of their investors.  The balance of how much the company should pay in dividends or other things counted as returns on investment (like stock splits) vs. the financial needs of the company is not a trivially easy question.  Companies have to balance their expenses vs. their income and a host of other things.  The idea that there should be no profit is pure idiocy.  Why would anyone go into business if there's nothing in it for them?

If history teaches us anything, it's that the free market is better at solving problems like wage levels than big governments.  We can cite examples all day, but here's a few.  There are places all around the country where higher minimum wages have been mandated.  The amount of troubles they've had are directly related to how much increase was mandated.  Seattle workers found they had less pay when the hourly wage went up.  Some lost their jobs as the companies went out of business.  There's a similar case study between Wisconsin and Minnesota that shows where the minimum wage was mandated higher, job growth lagged behind.  The kicker is that Minnesota's minimum wage law wasn't as bad as Seattle's, yet it still happened.  How long before all minimum wage jobs become robots and self-service kiosks?  

The new face of McDonald's  (Getty Images)

The guys at Values & Capitalism mentioned an aspect I'd not thought of.  Big companies, like Disney, are better able to handle these laws than smaller companies.  In their example, minimum wage was increased from $9 to $15/hour, the equivalent of a $12,500 per year tax.  The small restaurant, the small business can't ignore that. 
Some advocates of the $15 minimum wage wish to “stick it to the man,” hitting the billionaire CEOs. This small business CEO, however, claims that “last year, my employees made more than I, the owner, did. I am still trying to pay off the line of credit that got me through the recession.”
Could big businesses be part of the minimum wage talk?  We've seen many times that big businesses are in favor of "lawfare" and using the law to keep small companies from becoming a threat to them.  It's not out of the question. 

This week, we read that medicare is going bankrupt sooner than expected; Bernie and the Evil party are still saying Medicare for all.  People who can't understand what you just read rally for it, just as they rally and strike to hurt themselves by raising the minimum wage.  We try to tell them it's not going to work out the way they think, like we'd tell a 6 year old they really shouldn't stick their finger in that candle flame, and they respond by calling us "Hatey McHater". 

Thursday, June 7, 2018

Finally Done With The Replacement

The replacement for the cylinder I ruined about two weeks ago is complete and ready to put aside for later (except for a little cleanup).  This is it immediately after the last cut completed; not cleaned up at all. 

The fins and slots in the end are matched to those on the diameter of the cylinder: 3/32 (.094") wide with 3/32 spaces.  Just as the slots on the diameter were cut to 3/32 wide with a cutoff blade in that width, for these I had to buy a slitting saw blade that width.  I had some trouble with the first slot and didn't realize what was wrong for an embarrassingly long while, (the spindle's R8 taper was loose) so the first one has varying widths - which you can see if you look at the right end of the cut (the bottom).  It's a little stepped.   

After the first one, I decided it would be smart to write a little G-Code to eliminate the possibility of entering the wrong commands.   I lowered the slitting saw the expected amount, just barely cut into the end about .003 or .004, then used calipers to verify the fin being started was the right thickness.  If it was off slightly (the second one was off because it referenced the first slot), I corrected it, then ran the code to cut the slot.  Each slot took almost exactly 6:00 minutes.  

Somewhat cleaner at this point, just not deburred, yet. 

There are some marks from being in the vise that I need to either address or live with, and it has a bit of oil residue on it.  A little cleanup is needed. 

The next part is probably going to be the flywheel.  At 3-1/2" diameter, it will be the largest thing I've ever put on a lathe.  I not only had to buy a larger chuck for my big lathe, I'll have to use the "outside jaws" on it.  Aside from size, though, it will be just like the one I drilled on the rotary table for my first engine. 

Wednesday, June 6, 2018

Miss America Contestants to Drop Their Swimsuits

There it is: the headline I've been waiting to write for days.  Thank you! Thank you! I'll be here through the weekend.  Remember to try the veal parmigiana, and for God's sake, tip your waitress.

The real story is that the Miss America competition is being reformed in this "PoundMeToo" age and they're going to drop the swimsuit competition.
ATLANTIC CITY, N.J. –  The Miss America Organization is dropping the swimsuit competition from its nationally televised broadcast, saying it will no longer judge contestants on their appearance.

The competition began nearly 100 years ago in Atlantic City, New Jersey as a bathing beauty contest designed to keep tourists coming to the seaside resort in the weekend after Labor Day.
Gretchen Carlson, a former Miss America who is head of the organization's board of trustees, made the announcement Tuesday on "Good Morning America."
"We're not going to judge you on your appearance because we are interested in what makes you you," she said.
Can they survive? Mrs. Graybeard summed it up about as well as can be when she said, "men watch the pageant for swimsuits; women watch it for the gowns, fashions and the other stuff. Each one has something to watch if the other turns it on first. What happens to that audience?"  Which is too bad, because Miss America is also dropping the evening gown competition

For her part, Gretchen Carlson doesn't think it will make any difference.  She said, "the swimsuit portion is not the highest rated section of the broadcast. Viewers seem to be more interested in the talent competition," adding
“We are no longer a pageant, we are a competition,” she said. “We will no longer judge our candidates on their outward physical appearance.”
 Perhaps not surprisingly, the actual contestants - present and past winners - aren't uniformly considering it a good change.   Lea Schiazza, a former Miss Pennsylvania, asks if her winning a swimsuit competition trophy is now something that makes her "not good enough" now.
People have been arguing for years over the validity of a competition that awards scholarships for T-and-A. Feminists say there is no place for it in today’s society. People who have never been in a pageant say that the women are being exploited by walking down a runway in a swimsuit and high heels. And women who are supposed to be supportive of other women’s choices, find it all degrading and humiliating.

I say, walk a mile in my high heels and bikinis. I’d like to say two other words to them, but I don’t like confrontation or getting beat up.
Similarly, 2013 Miss Georgia, Carly Mathis, took to Instagram to voice her displeasure, saying “But if I’m going to make my mark on history at least I did it looking like this.”  Contrast them with Heather Kendrick, who held the title of Miss Michigan 2017, and praised the shift
With the move, Kendrick said, “we are taking the focus off of physical appearance and on to what’s in our brains and what’s in our hearts, and that’s really what Miss America is and stands for.”
To be honest, it has been so long since I've watched a pageant on TV that I didn't really know they were still broadcast.  My prediction is that they may have a ratings bounce this year as people tune in to see just what the new competition looks like, but I suspect they'll loose whatever audience they have now.  Will they generate a new audience for the new product they're selling?  We'll see. 

Miss America 1939.  Patricia Donnelly.

Tuesday, June 5, 2018

My Sigh of Relief Was Probably Audible in Georgia

When I got the fins cut off.

There are two operations left before I take this off the table and start on the next part.  First is to cut an opening in that side (that's facing up), centered 1/2" in from the left end, 1/4" wide and 3/4" long.  At the shallowest (in the center), it's about .060 deep; at the ends of the cut the metal is .230 thick.  Still, it shouldn't be terribly hard.  Maybe drill three 1/4" holes and mill out the web that's left between the drill holes.  The second operation is to cut heat sink fins in that pristine left end of the cylinder.  This will be done with a 3/32" thick slitting saw purchased for this reason.  Those follow the same pattern as the fins on the rest of the cylinder, fin and space are both 3/32 wide with 3/16 from the edge of one fin to the next.  The fins are also 3/16 deep, while the others were 1/4" deep.  3/16, or 0.188" steps will be getting a lot of use.

Neither of those operations seems particularly scary, but while I've used a thin slitting saw blade on my light duty Sherline mill dozens of times, I've never used one on the big machine and never to do something like this.  Take It Easy will be the mode of the day, and not an Eagles song. 

Monday, June 4, 2018

Your WTAF? Story of the Day

Where "A" stands for actual.

Thanks to a link at WUWT, we find a Daily Mail story that a man who claims to be a time traveler from the year 6491 and who is trapped here in 2018 passed a lie detector test about his story.
A time traveller who believes he is from the year 6491 but got stuck in 2018 when his time machine broke down, has allegedly passed a lie detector test.

James Oliver's story was doubted but paranormal experts say they were blown away when they put it to the test, because the results showed he was telling the truth.

Mr Oliver claims he lives more than centuries in the future but was sent back in time.

Paranormal YouTube site ApexTV carried out an experiment, which had bizarre results.

Mr Oliver passed every question.
Why is he trapped here?  Simple!  His time machine is broken.  Unlike the plot of Back the Future in which Marty McFly gets stuck in the past because he needs "1.21 Gigawatts" for the Delorean to take him through time.  Other than that, the plot is kinda similar.  Then why, oh why is this "strange visitor from another planet time" here?  Why to tell us about the global warming and one world government, of course!
According to Mr Oliver global warming is going to get worse and our planet is going to get hotter. He also says there is a United Nations style system of planetary leaders to ensure peace.
The piece is so absurd it's funny.  To their credit, the Mail doesn't give much credibility to the story, and reports the absurdities with a straight face.  You get such gems as:
'Where I'm from, the years are longer.
'But we have gifted mathematicians who work to calculate our years from those from other civilisations.'
Oh...Kay... But I think that's simple multiplication, not advanced math.  Maybe in 6491 the ability to use a four function calculator requires "gifted mathematicians".
Although the man has a Birmingham accent, with a US twang, he claims he is from outer space.
Describing life lightyears from now, he says more species and planets are discovered – and that there are fights coming between humans and aliens.
Of course, "light years from now" is incorrect.  Light years are a measure of distance, not time, so it either means years from now light years from here.   

The important part, and I'll bet a lot of you have said this already: a "lie detector" does nothing of the sort.  It detects stress and discomfort of the participant.  If he showed no such reaction, it didn't "prove he told the truth", it means either (1) he honestly believes what he's saying and feels no stress, or (2) he has experience with, and possibly training for, taking polygraph tests.  There are places where one can get trained to pass polygraph tests.   Decorum says I should leave it there.

Anybody else notice the year 6491 is 1946 spelled backwards?  Just a coincidence, I'm sure.  Both the ApexTV guy and James Oliver look too young to know anything about 1946. 

From the Daily Mail, but the photo is clearly labeled copyright YouTube/ApexTV.  The 17 minute video is here

Sunday, June 3, 2018

For Radio Amateurs Who Drop By

Of course I talk about ham radio, but not much and not often.  The index at the bottom of the right column shows 53 posts before this one with the label "radio". 

Ham radio has been described as "a thousand hobbies with one name" and that's pretty much right on.  There are probably a thousand things to emphasize depending on your interest, from the emergency/SHTF/Tactical radio that is blogged about the most in the places I see, to building your own gear, to uncountable number of technical aspects of the hobby, to experimenting with different modes like Slow Scan TV, fast scan TV, to, well, far too many to mention. 

I've always been oriented to the techy side (surprise?), building gear, writing software, semi-automating my station and so on, with an emphasis on testing the limits of the station.  It's pretty common for someone seeing a ham's station for the first time to say, "how far can you talk with that?".  I've always been interested in testing just how far I can, and always pushing those limits. 

Probably the thing I find the most interesting in radio is propagation - how the signal gets from one station to the other - and especially the ionospheric propagation.  This can turn into multiple pages itself, but the ionosphere is a layer of the atmosphere where the molecules present in the lower atmosphere are ionized by incoming solar radiation, and the air is so rarefied that it takes long times for ions to bump into something that makes them neutral again.  ("Do you think you're ionized?" "Yes, I'm positive") .  The ionosphere, in turn, is characterized as having several layers, with each layer's name changing with height.  The lowest, densest layer is called the D layer, and as we look farther vertically, they go through the E and F layers.  During periods of high ionization the F layer can further stratify into F1 and higher F2 layers.  The ionosphere expands and contracts, getting taller or shorter with incoming solar energy.

In general, the higher layers are active when the sun is overhead, but even then are dependent on the solar energy output which varies day by day, with the solar cycle, with (possible) grand cycles of solar activities and so on.  Generally, the type of propagation that gets hams excited is from the F2 layer, for a simple reason: it's the highest layer, so signals "reflect" from farther up and can go farther around the world. 

There are other types of propagation but tonight I want to talk about one that has been doing phenomenally well lately, called Sporadic E.  Sporadic E has been known for a long time, but "sporadic" in the name is an indication of the toughness of predicting when it will occur.  We know that it's caused by fleeting clouds of sufficient density in the E layer, and that it tends to occur more at certain times of years than others (now in the northern hemisphere).  We know that it tends to form later in the day and linger into the evening; that is, you'd be more likely to find it at 3PM local than 3AM local.  Finally, we tend to observe it on higher frequency bands, especially 28 MHz and up; in the US, 28, and 50 MHz, although it happens on occasion on the 144 MHz band.  Hams have long said that sporadic E clouds form above the tops of thunderstorms - long before mechanisms that could extend the charge into the ionosphere, such as red sprites or dark lightning were discovered. 

The last week or so has brought levels of sporadic E propagation that I've never seen before.  There are websites where hams report other stations they've heard or contacted ("worked"); the one I've been using for years is DXMaps.  This is a screen capture from a few minutes ago; around 7:30 PM EDT, 2330 UTC in the UK and earlier in the morning as one goes farther east into Europe. 
The density of reported paths is so high it's hard to make sense of it, but I call your attention to the long arcs from US into Europe.  In some of those countries it's past midnight, yet they continue to hear and work each other across the continent and across into the US. 

I don't have any real numbers on how this compares to other times in the past, but I've heard and worked more Europeans in the last five days than at any time before. 

What's going on?  We're supposed to be in a solar minimum that's going to impair propagation and make things worse.  A closer look at the DXMaps website shows a list view of reported contacts.  About 2/3 of them are using a rather new digital mode called FT8.  All of my recent contacts with Europe have been using that.  FT8, part of package of advanced digital modes from Princeton University physicist Joe Taylor, burst on the scene last year, and has become the "new hotness" of ham radio modes.  All of the modes in Joe Taylor's software package are run by connecting the radio's audio input and output to your computer, letting the sound card digitize the audio and pipe the samples to the software for processing.  FT8's strength is that it embeds robust error correction and signal processing to allow copying weak signals easy.  Considering it's an offshoot of another program of Joe's designed to help operate moonbounce, usually very weak signals, that makes sense.  Moonbounce or EME (Earth-Moon-Earth) is reflecting VHF/UHF or microwave signals off the moon to allow any two spots on Earth to communicate (if they can both see the moon). 

Clublog, an online service to help hams get confirmations from those stations they've contacted, charts the growth of FT8 vs the most popular modes in log submissions during 2017.  The kicker is that FT8 was barely introduced until about midway through the year.  I had my first few contacts with FT8 last July, when it was still beta software. 

The last digital mode to take ham radio by storm was another "sound card mode", PSK31.  By contrast, PSK31 is a conversational mode (hams call that "rag chewing") with freeform contacts.  Type as much as you want and the other guy will receive - or not.  FT8 is much more structured so more of a contest/fast contact mode.  Each side transmits for 15 seconds alternating with the other station.  When things are working well, a contact can be completed in one minute.  If the messages aren't decoded properly, that can stretch out, but no transmission is longer than that 15 seconds (a small number of characters). 

I know some number of hams drop by and read this.  If you're interested in 6m Sporadic E, get that radio on.  If you haven't worked FT8, it's a bit complex to get started with, but if you can run PSK31 you have all the hardware you need.  Sound card to radio. 

Saturday, June 2, 2018

DOE to Fund $72 Million Bird Incinerator

That was a deliberately inflammatory title - and deliberately chosen pun to go with it.

The actual story is that the DOE has agreed to $72 million dollar funding of another concentrated solar power system like the famous Ivanpah facility in the California desert.  Ivanpah is famous for incinerating birds that come to feed on the insects being incinerated by the solar concentrater.

The goal of the project is to increase the temperature of the working fluid up to 700 C (1292 F).  Ivanpah and some other facilities run at temperatures from 300 to 550 C.  Concentrated Solar Power (CSP) systems are more efficient the higher the temperature difference they work with.   Increasing the temperature to 700°C promises greater efficiency.  They're calculating they could reach 50% efficiency. 
Light beams can be concentrated by refraction through a lens (a magnifying glass), or through curved mirrors, to produce extremely high temperatures. Commercial scale CSP facilities like the recently completed Noor I power plant in the Sahara Desert in Morocco use 500,000 crescent-shaped mirrors that track the sun across the sky. Noor I can produce up to 160 megawatts while operating at almost 400°C. Similarly, Ivanpah, the world’s largest CSP facility—located near the California and Nevada border—has 300,000 mirrors that concentrate the sun’s energy onto three 459-foot-high towers. Power production from the 3,500-acre Ivanpah site is rated at 377 megawatts with operating temperatures as high as 565°C.
The reason they're funding this as research is that the current technologies, which use molten nitrate salts to transfer the heat, won't work at the higher temperatures.  The setup is a competition between three contenders that will be tested by different teams:
  • Brayton Energy, Hampton, New Hampshire: $7.6 million — gas phase system
  • Sandia National Laboratories, Albuquerque, New Mexico: $9.5 million — falling particle system
  • National Renewable Energy Laboratory (NREL), Golden, Colorado: $7 million — liquid (molten salt) system
Over a two-year period, each team will develop and test materials, concepts, and critical components using its assigned thermal transport technology. Each will also create detailed plans to build an integrated CSP facility. At the end of the two-years, one of the technologies will be chosen to move ahead with the construction of a $25 million pilot facility over a period of three years.
I find it curious that nobody is talking about using molten sodium (metal), which has been researched extensively by the nuclear power industry (remember KRUSTY the NASA nuclear power project? It used molten sodium).  Sodium melts at conveniently low temperature, 97.72 C (207.9F) and doesn't boil until 882.85 C (1621F). 

The big picture is that the DOE is trying to drive more energy production to solar, and if they achieve 50% they'll be doing better than practical photovoltaics (PV; solar cells) do.
The CSP project announced is part of a bigger effort on the part of DOE to drive the cost of solar energy down. For example, the target for the cost of PV is $0.03 per kilowatt-hour (kWh) by 2030. The CSP target is $0.05/kWh by 2030. But the PV costs do not include storage, where the storage and ability to generate electricity when the sun isn’t shining is built into the thermal CSP system. Shultz notes that if a plant has 12 or more hours of thermal energy storage capacity, then it can operate on the order of 70% of the time. But a PV without storage can only operate 20-25% of the time. “What we see, if we hit these targets, is that CSP seems to have a lot of value,” said Shultz.

The Ivanapah CSP facility. 

We can argue this isn't a valid function of the federal government, but that's like arguing that minimum wage laws harm workers and raising the minimum wage will cause inflation.  In both cases we'd be right and nothing would change.

Friday, June 1, 2018

Ready for Round 2

Setup the rev 2 cylinder in the vise with a few mods from last time. 

First, on a recommendation from Irish, I milled a short, wide "trough" along the length of the soft jaws.  A little experimentation with 3D CAD showed me that a wide, shallow cut was a good approach.  The cut is centered around 1" above the floor of the vise, and if everything works as intended, gives me three lines of contact instead of just one.  The cut width was set by moving the cylinder into the jaw until it started to get too close to the counterbored screw holes (dashed lines, lower right) and then measuring how long the line segment is.  Then I redid the drawing using a standard sized end mill and remeasured the depth.

This is a single pass, just about 1/32" deep with a 1/2" diameter end mill; an easy cut.  Here's a view from the end without the pedestal where it's easiest to see, showing how the cylinder gets contacted in three places and not just one in the center.  (Yes the camera's rotated; I'm not trying to look like an annoying commercial, it's hard to get the camera where it can see this).  The vise jaw is the wall with horizontal lines that look like stacked bricks, made by the end mill that cut back the jaw, while the big round thing is part of the end of the cylinder.

After I added some thin cardboard for extra contact roughness, I put it in the vise, ensured it was level to a dial indicator, and tightened it up. 

I'll probably try to cut it in the next day or so.  Once I'm sure I've done everything reasonable to not barf it up again.

Thursday, May 31, 2018

Genuinely New Ideas in Rocketry Are Rare

Vanishingly rare.  I don't know if this is the first time it has ever been discussed, but according to the website, a collaboration between two universities is researching a booster that literally consumes itself on the ascent to orbit. 
In a paper published in the Journal of Spacecraft and Rockets, engineers from the University of Glasgow and Oles Honchar Dnipro National University in Ukraine discuss how they have built, fired, and for the first time throttled up and down an 'autophage' engine which could change how small satellites are sent into space.
'Autophage' translates as 'self-eating', and the concept is that instead of fuel tanks and the superstructure that the booster provides, a vehicle powered by an autophage engine would consume its own structure during ascent.

A typical booster, like the Falcon 9 boosters that SpaceX recovers and reuses, contains liquid fuel and oxidizer tanks along with plumbing to connect those tanks to the booster's nine engines   Big boosters tend to be liquid fueled, with notable exceptions for the large solid rocket boosters used in the Space Shuttle program, and large vehicles like the Delta IV Heavy.  Typically, the booster's weight is several times the weight that can be delivered to orbit.  For every pound of weight added to payload, the vehicle has to carry more fuel, and the fuel to lift that fuel. If the booster's weight was usable fuel that would be an incredible advance. 

The autophage engine concept allows weight from the plumbing tanks and other essentials to go into larger cargo capacity.  If the same technology were to be in upper stages, less debris would survive to make it into space.  No boosters (or less junk) to recover or dump in the ocean; and less debris from upper stages.  More efficient from all perspectives.
The autophage engine consumes a propellant rod which has solid fuel on the outside and oxidiser on the inside. The solid fuel is a strong plastic, such as polyethylene, so the rod is effectively a pipe full of powdered oxidiser. By driving the rod into a hot engine, the fuel and oxidiser can be vaporised into gases that flow into the combustion chamber. This produces thrust, as well as the heat required to vaporise the next section of propellant.

Simply by varying the speed at which the rod is driven into the engine, the researchers have shown that the engine can be throttled – a rare capability in a solid motor. Currently, the team have sustained rocket operations for 60 seconds at a time in their lab tests.
I'm having a difficult time visualizing how this could work.  The vehicle has a "combustion chamber", or chambers, so some structure needs to last the entire time it's burning to hold the combustion chamber and engine nozzle(s) in place.  If some control or telemetry to the ground is involved, that will have to be in the booster just as it is now, and will get thrown away, too.  If the autophage motor is just burning along the length of the body, it's not that different from any solid rocket motor; those tend to burn from the center outward along the entire length of the body.  Having the ability to throttle the engine up and back is unusual.  Solid motors are typically said to burn until they burn out.

The researchers describe it in starkly different terms than I do and don't address my thoughts at all.  Dr. Patrick Harkness, senior lecturer at the University of Glasgow's School of Engineering, puts it this way:
"The propellant rod itself would make up the body of the rocket, and as the vehicle climbed the engine would work its way up, consuming the body from base to tip.

"That would mean that the rocket structure would actually be consumed as fuel, so we wouldn't face the same problems of excessive structural mass. We could size the launch vehicles to match our small satellites, and offer more rapid and more targeted access to space."

A small autophage motor at the University of Glascow.  University of Glascow photograph.

Wednesday, May 30, 2018

Ignore That Financial Mess in Europe, Roseanne Tweeted Something!

Is it 2006 all over again?  Is the economy truly better or are we just seeing the effects of a few local, isolated actions.

Maybe you didn't see the story that Italy is slipping into a financial crisis, but you might have seen the US stock market dropped about 400 points on the Dow.  Italy is why the Dow dropped.  Tokyo's NIKKEI and Australia's ASX200 were also hit by Italy's troubles yesterday.

At root is the same problem, the same rot affecting every country from US to China; Germany to Greece.
Italy risks careening into a new financial crisis after the Bank of Italy said the country’s leaders could not “disregard” financial constraints and its commitments to Brussels.
Escalating worries that Italians may be poised to take a tougher stand against the euro prompted a round of accusations and finger-pointing among EU officials, including a rare admonishment by Donald Tusk, the European council president, who said EU institutions needed to show “respect to voters” in Italy.
In October of '16, I posted an introduction to some of the players in the mess today, as well as a "keep your eyes out" for things going on Italy.  It centers on the 5S Movement, which began as joke and turned into a populist, "Brexit-like" party movement.  iExit?  The latest issues appear to stem from a need to form a "coalition government" between differing parties and their inability to do so. 
The crisis was set off late last week when the Five Star Movement (M5S) and Lega, which had been attempting to form a government, insisted that the president, Sergio Mattarella, approve their choice for finance minister, Paolo Savona, a fierce critic of the euro. Mattarella vetoed the nomination and the incoming populist government collapsed before it had taken power.

The president appointed a new prime minister, Carlo Cottarelli, a former director at the International Monetary Fund, who was expected to present a list of ministers to Mattarella on Tuesday. The president’s spokesman said after a meeting that the two officials would meet again on Wednesday morning.
Add in that the European Central Bank is struggling to keep control in the country, and you get quite a mess.  Ignazio Visco, chairman of the Bank of Italy, said the country was at risk of losing the “asset of trust” with investors.  On Tuesday the Italian bond spread, a leading indicator of investor concern, rose to its highest level in four years.

Italy is the third largest economy in the European Union, behind Germany and France (and I'm leaving out the UK due to the ongoing Brexit).  If Italy were to collapse or go into a deep economic crash, it threatens the entire EU.  Italy has one of the largest national debts in the world and an unemployment rate over 11%. It's economy is now worse off than it was before 2007. The Italians tried, like everyone else, to borrow and spend their way out of the financial crisis, but they never recovered.

The fundamental problem, as I must have said at least five hundred times in the 2800+ posts of this blog, is that the world is awash in debt.  The total debt in the world now is $164 trillion.  Annual world GDP is in the vicinity of $70 trillion so this is well over two years worth of "all the money in the world" to pay off that debt.  That figure ($164 trillion) is not counting the unfunded liabilities in the world's economies, which currently add about $115 trillion in the US alone, as can be found on the Debt Clock.  Unfunded liabilities shouldn't be counted as debt; we haven't spent that money yet. They're more like a promise to spend in the future, however if we can't meet our liabilities now and can't live with a balanced budget it's reasonable to question where that money will come from. 

In the wake of the "great recession" of 2008, the world's central banks went on a stimulus binge like the world has never seen.  Not just the trillions of dollars created out of thin air here in Quantitative Easings; think of China's bridges to nowhere and ghost cities.  If anything, China has worse economic problems than we do.  All the central banks: the Bank of Japan, the European Central Bank, the Central Bank of China: all of them have created money from nothing. 

The US economy has shown some positive reactions to Trump's tax cuts and the news has been mostly good.  The labor participation rate hasn't improved to any noticeable extent since the middle of Obama's second term, though, still on par with the rate in 1978, and I honestly don't know what's up with that since we keep hearing about record low unemployment and other good news.  I note that some aspects of the Dodd-Frank banking regulation bill have been cancelled.  I personally never heard anything good about Dodd-Frank from any financial writer who seems to know the industry, so I view that as good. 

The world, I believe is in a precarious position economically.  Am I just a "too small thinker" to live with a world that measures debt in the hundreds of trillions pf dollars?  Could be.  On the other hand, I don't believe we're immune to any form of economic problems, and I still believe what can't go on forever won't go on forever, because I still believe that infinity is a very handy concept in math and science, but a rotten way to run an economy.

As for when this may happen, I've given up on guessing.  I've posted so many "real soon now" warnings in the life of the blog that I think decorum tells me I should say no one can predict it.

Italian actor and comedian Beppe Grillo; originator of V-Day and the M5S party.  Getty Images.

Tuesday, May 29, 2018

Rev 2 is Mostly Ready

Revision 2 of the cylinder for my Duclos flame eater engine, to replace the one I destroyed Friday, will most likely be ready to put back on the mill tomorrow.  I expected to get this one in a small fraction of the time spent on the first, since most of the time spent on the first one came from trying to figure out how to do certain things with tools I have (instead of immediately buying more new tools) and it did.  I spent about a week of "4 hour days" working on the first one, and about three of them on the second. 

It's not quite done.  The narrow diameter on the right needs to be reduced a little to press fit the pedestal onto this, and it needs to be cut off the extra rough stock that you can see in the lathe chuck on the left (wrapped in thin cardboard).  The same tool that made the fins on the cylinder will be used for that.  Most likely.

The truly detail-obsessed* among you will notice this one is different from the other, which is to say I also learned from my mistakes.  If you count, you'll see this one has nine fins; the other had seven and a smidgen of an eighth.  The print I'm building-to shows the slots and fins both being 3/32 wide (.0938").  On the first one, I just advanced the cutting tool by twice that and expected it to turn out.  I ended up with tolerance buildup - most of the fins and spaces ended up 7/64 wide.  This time, I had the idea to use the blue layout fluid (you can see a little remnant of it in the pic) and layout where edges should be.  Then I marked the edge of a space (between fins) by cutting a couple of thousandths deep; it allowed me to measure how wide the fin would end up and I could move the edge to make sure the fin was really .094 wide.

There are other small differences that I won't get into.  Think of it as a challenge.

I expect to spend more time agonizing over the setup with a dial indicator, verifying that it's the same height everywhere, and maybe putting a foot long pipe on the vise handle to clamp it tighter.  Basically, all the little tricks I've come across will get used, unless they contradict each other or something else.

( * "detail-obsessed" sounds better than "anal-retentive" doesn't it?)

Sunday, May 27, 2018

Memorial Day 2018

I know that for a lot of the country, Memorial Day is the unofficial start of summer and there will be cookouts and parties at the lake or beach or park.  Allow me join the chorus of folks saying that while you're enjoying your day, be it beach, barbecue, pool or whatever, take a moment to remember and thank those who have given their all in service to us.  Some don't get the chance to have that cookout, or be with their loved ones. 

There's a couple of pictures that I regularly run for Memorial Day, and this year I'm going to go with the image from 2011 that touches me by having an element of the unexpected. The images of women who have lost their husbands are gut-wrenching, but a dog isn't generally expected to have feelings this deep.  I went looking for the a photo credit and I found one this time.

In a final act of loyalty, Hawkeye, the dog of slain Navy SEAL U.S. Navy Petty Officer 1st Class Jon T. Tumilson walked up to his fallen master’s casket during the funeral in Rockford, Iowa, and then laid mournfully down beside the body for the rest of the proceedings  [Note: Petty Officer Tumilson was one of the 30 killed in Afghanistan in the shoot down of Extortion 17 which the families blamed squarely on the Obama administration - SiG]
Far too large a portion of the ruling class could use Hawkeye's loyalty.  There are signs that's improving, no matter if it's temporary or not.  The others could ponder showing less humanity than a dog.  

No barbecues for us.  We're still under the clouds associated with that Tropical Storm over in the Gulf. 

And ... It's Ruined

The cylinder of my flame eater engine, that is.

The last thing I mentioned in that post was planning to make a set of thinner, taller jaws for the vise because the existing set was grabbing it below the centerline by a little over a quarter inch.  That creates a force to push it vertically out of the vise - or cuts a notch into the fins.  The SHCS that came in the vise were too tall to use on anything much thinner than the factory jaws, so I found some low profile button cap screws to order.  I figured I could thin the jaws by about an eighth inch on both sides, giving me a quarter inch more opening.  Oh, yeah, I ended up leaving the soft jaws 1-1/2" tall. I might lower that a little.   While waiting for the screws to arrive, I made the jaws out of some quarter inch thick plate I had.  They fit perfectly.

So now it was time for a test fit.

Seemed like it was all good. The gap between the bottom of the cylinder and the vise jaw figured to be 1" and I had a left over block of 1" bar stock.  (Look on the left between the closest jaw and the cylinder).  It felt very secure. It took me a while to figure out how deep to cut the fins and the 1-1/2" diameter part of the cylinder over on the right end because it's never really specified on the print. The print does show that the flat should be 1" wide, so a little geometry (and an online calculator) showed me I ought to cut it  0.190 - about 3/16" deep.  (Seriously - how deep do you cut that?  I think this is similar to what's called Geometric Dimensioning and Tolerancing, or GD&T. )

A friend convinced me to put an extra clamp across the top - I guess he was afraid of aluminum jaws replacing 3/8" steel - so I added that. I cut the flat over the base of the cylinder in a few cuts, .025 deep at at time (3/8 end mill) and it went very well. Which led me to decide to take off the 3/32 wide fins in a couple of passes. First pass at 0.100 depth followed by a second pass at 0.190. When I was done cutting off all the fins I thought I'd move the end mill toward the base as a spring cut (a second cut with the same settings; it removes some metal that gets compressed by the cutting forces in the original cut and "springs back" to a higher level), just to level out any cutting marks. Instead it dug in and ripped the cylinder open. Look at the shelf on the end where I stopped the cut. That's a deep cut at the far end. 

You can see how bad it is. The Z axis on the mill never went below -0.190", so as I moved right to left along the cylinder cutting the fins off, the cylinder must have pivoted and lifted the left end. I sure couldn't see it happen. You can measure the diameter to the flat by putting the calipers on the fin and the flat at both ends. The end closest to the camera is 1/16" smaller than the end by the pedestal. The flat spot on the right end of cylinder after the fins was supposed to measure 1.000 and measures exactly that. Like I say, the entire piece was cut with the EM never going deeper than -.190".

In the aftermath of trying to figure out what went wrong, I focused on the idea that the cutter was getting lower as I made the cuts, which were right to left in the pictures here.  To cut off the fins (3/32 or .094 wide) I raised the Z-axis of the mill from -.190 to -.100, moved to the next fin, made a cut, lowered the cutter back to -.190 and took another pass.  As a diagnostic, I set an indicator on the spindle, raised and lowered the cutter back and forth between -0.100 and -0.200 about 40 times.  The indicator never showed a change in position, which means the cutter wasn't getting lower every time I raised and lowered the mill's headstock. 

My guess is that the cylinder pivoted because even with the taller jaws and the 1" bar stock spacer, the contact area holding it is still pretty small.  Theoretically, the contact is only a line with one point on each fin; practically, the metal will spread out a little, but it's still a tiny contact area.  Since the cut is deeper on the left, that means it was rising into the cutter, pivoting around the right end.  There wasn't enough holding force to keep the cylinder from rotating. Maybe I should have made really light cuts? Maybe something between the jaws and the cylinder to keep it from sliding, like very light sandpaper or cardboard?

This was Friday and I've begun work on the replacement cylinder.  I don't see any way I could fix this one.  Maybe with welding equipment and an expert's touch, neither of which I have, but I do have more pieces of 2-3/8" diameter bar stock cutoffs that I can make into the new cylinder. 

I'll be the first to admit that my main problem in doing machine shop work is that I Know Nothing.  Well, not quite nothing, but I'm totally self-taught and when you're self-taught there are always holes in your knowledge.  If anyone sees this and has ideas on how not to make this screwup again, let me know! 

Saturday, May 26, 2018

A Visitor to the Backyard

We had a visitor to the yard that we've never seen before. 

That thing it's standing beside is the outdoor half of a mini-split air conditioner in the workshop.  Mrs. Graybeard was out looking at setting up to do some cleaning and noticed him.  There was another on a neighbor's wooden fence not 6' from us. 

Neither of us knows a hoot about owls, but this appears to be an Eastern Screech Owl.  Everything about habits and habitat seems to match up.  This is a corner of the lot where three neighbor's trees overlapping turn it into a fairly dense wooded spot.  The fact that they're supposed to be nocturnal and daytime sleepers explains the tired-looking eyes.