Thursday, January 14, 2021

The Intersection of Old Film Photography And Modern Makers

Something completely different that I find insanely cool, although I have no particular desire to own one or get involved.  

First, a little Grandpa Simpson story to get you acquainted.  When I was first getting interested in photography, the only big name cameras I knew were 35mm.  Nikon.  Canon.  Pentax.  Still the big names in photography. It took me a few years to get one and by then I had learned the reality that if you want to enlarge a picture, the bigger the negatives the more you could enlarge it.  I learned about view cameras that took glass plates as big as 8x10.  I had seen that for trips to the moon, not just once in a lifetime, but once in human history photography, NASA had used Hasselblad cameras as they had been using for most of the space program.  For use on the moon, they couldn't bring a large format view camera, taking pictures was a sidelight to the other things the crew had to do, so they brought a medium format camera, generally 6 by 6cm, smaller than the impractical cameras but considerably larger than the 35mm film at 24 by 36mm.  The film format you can buy is called 120 or 220, depending on the number of shots it will allow.

The advantages of the bigger film led to medium format being a high end camera for the very serious photographers or those that could justify the expense.  That was the case in the 1970s and for as long as I kept track.  

Imagine my surprise when Digital Photography Review (DPR), the weekly photography newsletter I get, featured an article, "These open-source medium format cameras are 3D-printed."  The article links to the store and story of Dora Goodman in Budapest, Hungary.  Ms. Goodman's company gives away the plans to print the camera parts yourself, or will sell you a finished Goodman Zone camera body for as little as $113.40 while the holiday sale is still in effect.  The body appears patterned after a very popular medium format camera, the Mamiya RB67  (from Mamiya Sekor, another major Japanese camera maker).  It currently uses the Mamiya film backs, although they will be selling their own backs soon. 


Now this is simply a camera body; a light-tight box with ways to interface to a lens, a shutter, and not much else.  Especially not a lens.  You may know that in the 35mm world, a "standard" lens is around 50mm (its photographs match most closely to how we see real life than focal lengths much shorter or longer); in the 6 x 7 cm world the equivalent is around 80mm.  A quality 80mm lens is going to set you back much more than the cost of the body.  For several lenses, you might need to sell a kidney.

PetaPixel, a serious photography devotee's place, did a story on these cameras and has more depth and lots more pictures, and there's a ton of links on both DPR and PetaPixel.  Like I said, I think it's insanely cool although I don't have much interest in following into medium format photography again.  It's cool because it's part of the paradigm of the convergence, the new industrial revolution.  It's personal fabrication; the intersection of home CNC, 3D printing, continually more powerful digital electronics, into what's called the Maker movement, in which interested people out-innovate the big guys.  It's a drum I've been beating on for years.



Wednesday, January 13, 2021

A Remarkable Day at SpaceX Boca Chica

I've been watching the activities at Boca Chica for quite a while now, and today was probably the most remarkable day of testing I've seen.  Like many people, I started watching the Lab Padre feed around mid-day in hopes of a static fire test.  Last night, they had extended the 8A to 5P road closure and were working toward a static fire by 8PM (CST).  That attempt was aborted in the last minute, prompting concerns and belief that they'd be troubleshooting and trying to repair whatever it was.  After that I was expecting to see a static fire at some point, no matter how late in the day

I never expected to see three static fires in one afternoon.  They've never done three static fires in one day before.  I'm not sure they've ever done two within 24 hours before. 


As you can see from the text at the bottom, this firing happened at 12:28:51 local time.  Right away, it didn't look like last night's attempt.  Within seconds, certainly within a minute of last night's abort, the vehicle was venting large clouds and conventional wisdom was Starship was detanking.  That didn't happen after this firing.  Soon, someone posted that Elon said they were going to do multiple firings today. 


To be clear, that time tag is EST, so 1:06 at Boca Chica, roughly 40 minutes after that screen capture.  I'm not sure what he was referring to as "two starts completed," unless one was some other time. 

By the end of the day that doesn't add up because they went on to have two more static firings today; the three were at 12:28, 2:23 and 3:37 PM.  Musk later tweeted, "all three static fires completed & no RUDs!" (Rapid Unplanned Disassembly). 

The next big milestone is clearly their launch for their re-try to do the same hop that SN8 almost completed. They believe they've got a temporary fix for the pressurization issue in the small header tank that they experienced on SN8, although they're said to be trying to come up with a fix that doesn't depend on helium as this one does. That's one less thing to take to Mars and one that requires special handling.  That flight will probably be Friday, but I have a hard time keeping up with these guys.  I can see them going for it tomorrow if the situations allow.



While on the topic of space news, I went in search of when NASA intends to do a full up firing of their SLS core stage during its Green Run Testing.  According to the SLS website, NASA is now targeting this coming Saturday, Jan. 16 for the test. 
The Green Run test series is a comprehensive assessment of the rocket’s core stage prior to SLS launching Artemis missions to the Moon. The core stage includes the liquid hydrogen tank and liquid oxygen tank, four RS-25 engines, and the computers, electronics, and avionics that serve as the “brains” of the rocket. NASA has completed seven of the eight core stage Green Run tests, including loading and draining propellant for the first time during the most recent test, the wet dress rehearsal, on Dec. 20. During the upcoming hot fire test, all four engines will fire to simulate the stage’s operation during launch.
This will be a major milestone because the system has never been tested before and it will run for the full 8 minutes expected for a mission to orbit.  True, they're using space shuttle main engines (SSMEs) and those have an extensive and excellent life history, but the rest of the vehicle is nowhere near that mature.  The test will not be televised or video live streamed (at least this posting doesn't say so) but one may apply to listen to it by audio telecast on a conference call.  Details at that SLS Website link.



Tuesday, January 12, 2021

Welcome to Dystopia

If the last few days haven't seemed like complete dystopian life, I don't think you're watching.  Tech oligarchs ban speech they disagree with?  Parler getting dumped by Google, Apple and Amazon?  Dozens getting deplatformed everywhere from Twitter to Facebook?  AR-15.com gets dumped by their ISP with no warning?  

And then there's this, lifted mercilessly from Miguel at Gun Free Zone.


I don't think I've seen a more obvious or less clever trap in my life. The chances that this is real, constitutional conservative organization are right around the chances of winning Powerball - one in 250 million?  Is it Antifa, our government, Chinese government?  Harder to say. 

All of this just from the color scheme and general look.  It's so obviously communistic that I'd bet 80% of the parodies on The People's Cube look like this.  No US flag, no red white and blue, just red and yellow.  Are the three stars on Lady Liberty three of the four on the Chinese flags?  Since I mention the lady, notice that picture is swapped left to right - she holds the torch in her right hand not her left hand like this shows.  The only thing missing from a communist poster is the hand pointing the way to the glorious future. 

As Miguel points out, notice where it says "come armed at your personal discretion" while talking about going to the White House?  Unless you've just joined the world of concealed carry you should know that carry in DC is just about completely forbidden.  The only people who can carry in DC are approved LEOs, Military on duty or those who have adequately greased the palms of the local politicos.  If you open carry in DC, you're going to jail as soon as they see you. 

Suffice it to say, in the immortal words of Admiral Ackbar from the Star Wars universe, "it's a trap!"



Monday, January 11, 2021

So Why Should I Believe the FBI?

The headline said, "FBI warns 'armed protests' are being planned in all 50 states ahead of Inauguration Day" and caught my eye.  My first reaction was the post's title: so why should I believe the FBI?  Why should I trust them?  They've lost their credibility to me - speaking as an organization, of course.  I'm sure there are tons of employees there, agents to lab scientists, whom I could trust.  From the management side, the ones who would issue this sort of news?  Not so much. 

It turns out that linked story at The Blaze relies on ABC.  ABC?  Strike two against believability. 
Starting this week and running through at least Inauguration Day, armed protests are being planned at all 50 state capitols and at the U.S. Capitol, according to an internal FBI bulletin obtained by ABC News.

The FBI has also received information in recent days on a group calling for “storming” state, local and federal government courthouses and administrative buildings in the event President Donald Trump is removed from office prior to Inauguration Day. The group is also planning to “storm” government offices in every state the day President-elect Joe Biden will be inaugurated, regardless of whether the states certified electoral votes for Biden or Trump.

"The FBI received information about an identified armed group intending to travel to Washington, DC on 16 January," the bulletin read. "They have warned that if Congress attempts to remove POTUS via the 25th Amendment, a huge uprising will occur."
Riiiigghhht.  "Received information?"  Was that information supplied by the Southern Poverty Law Center, also called the Southern Preposterous Lie Center, by any chance?  Their motto, "attacking non-liberal groups for profit since 1984."

Peter @ Bayou Renaissance Man ran a piece today with extensive long quotes from Larry Correia and Tom Kratman summarizing how they see things today.  I strongly identify with this paragraph I pulled from Larry Correia.
People are confused and constantly bombarded by conflicting information, some correct, some bull****, and nobody knows what to believe because nobody trusts the people we are supposed to be able to trust. Then we have a super powerful global media complex that straight up gas lights everyone, and we're shocked the people have lost trust in information sources.
Yeah, that's where I am.  No trust in anything from the swamp. 





Sunday, January 10, 2021

The Major Pieces Are in Place

The big lifting/moving in the shop seems to be done with.  There will be lots of smaller things moving around, and maybe some of the bigger things making smaller moves, like a few inches here or there.  I can't get you a view like the overhead views from the drawings, but I can do photographs.

Looking toward the left.


Looking toward the right.


There were some surprises and gotchas, which always seems to be the case in any project.  For one thing, the distances I expected from the model didn't show up in real life.  I wanted enough distance between the table with the two small lathes and the big lathe to the right to get that chair (front left) between them to sit while working at the lathes.  According to the CAD drawing from the left wall to the base of the lathe should have been 11 feet.  I laid a tape measure on the floor and found it to be 10 feet.  Everything seemed to be where it should be and the right size, how could they be a foot different?  I've been around enough construction to know that sometimes dimensions on a drawing are viewed more as suggestions than requirements, but the distance from the left wall to the right edge of the back window was within a couple of inches of what the drawing said. 

I eventually just shoved the lathe and the new shelves toward the right. They may still need to move another few inches.

Compared to yesterday, you'll note that the computer was moved down to the right side of the bench along the back wall compared to the drawing that had it on the left.  My thought was that putting the computer between the small mill and small lathes would allow me to see either machine from the computer equally well, while working on the lathe before was much harder than working on the mill. 

It leaves me in a little bind because I had to use a special cable for the CNC control box I built for the big mill and needed to use an arrangement of cables and lengths for the three machines that was different from before.  Another example from the "you can't get something for nothing" file.  I need to get a short parallel port cable: DB-25 M-F.  Both the big and small mill work properly under computer control.  The compressor, visible along the back wall below the blinds, is hooked up to the Fogbuster cooling system.  The only thing I couldn't do tomorrow that I could do before this all started would be to use the CNC lathe. 

The next couple of days will be less strenuous, but I've moved some of the small tools I want in the machine shop over to the new shelves, freeing up room on the shelves in the woodworking area of sandpapers and odds and ends that are on workbenches. 

I need the space because I've decided to take the plunge into the world of 3D printing and I'll need a place for the printer.  I've ordered a Creality Ender 3 V2 (not from these guys, they're out of stock).  I've been diving into the world of getting started with one and the process is very similar to what I've been doing all along.  Parts are designed in CAD and then go through a different kind of CAM (Computer Assisted Manufacturing) program, called a slicer.  When presented with a solid model, all the CAM or Slicer knows is the outside.  You tell the slicer how thick the walls should be and how much fill-in is between the outside lines and it turns those into slices that the printer makes.  The printer puts down thin lines of heat-softened plastic. 

A machine tool CAM program outputs the path of a cutter that takes everything away except the shape.  A Slicer program outputs the path of the filament extruder that lays down the thin lines of the walls of that shape and the reinforcing plastic filled in between the walls.  Both use G-code, a language I already work with. 



Saturday, January 9, 2021

Things Are Moving - Part ii

I didn't finish the rearrangements today, but I didn't think that was sure.  Maybe a 75% chance I could, if everything went well and painlessly.  

I thought I'd step back and show some 3D models of the starting point and envisioned end point, along with explanation. Like pretty much all the 3D modeling I do, this was done in Rhino3D. It started out in '14, and has been updated and modified several times since. The main part of what I've been doing so far is in the metal shop area.  That's the top left corner in this model, which shows the way the shop has been laid out pretty much since '16 when the big mill CNC conversion was finished.


I've labelled the major parts.  The computer along the wall on the left (west) controls the Grizzly mill via that small white box to its right with some parts visible inside it, the CNC Micro mill (a combination of Sherline and A2ZCNC parts) and the CNC lathe (Sherline).  Both of those have small white boxes that don't show any parts inside (that link does).  There's also a manual (non-CNC) Sherline lathe on the bench aligned long axis perpendicular to the west wall.  It's a bit difficult to work on the CNC Sherline and look at the computer if I need to see the display, so that was a minor thing to correct.

There were two motivations for doing this; the big one is what I mentioned yesterday about walking around the shop to get a drill bit or a screw to check threads.  The light green rectangle marked "small shelves" is a bit over 2' long, 18" wide and 2' tall.  I needed more room there.  The other motivation is to clear out the area directly in front of and below the mini-split air conditioner, that beige rectangle running along the west wall (and 7' off the ground).  We clean the filter a few times a year, and it requires climbing on something to get to it.  Besides that, it's going on 7 years old (installed in May of '14) and that means chances of it needing repair are greater than zero and growing. The harder it is to work on, the more expensive the service call.

My first thought and model was to push the the two benches along the west wall over toward the top, getting closer to the big mill's enclosure.  To keep it from going into the enclosure, I had to move that to the right and that just moved lots more.  I eventually thought of swapping the mill enclosure with the two other benches, and arranging them differently.


The new shelves are visible just below the big lathe and were the first thing added on Thursday.  The two blocks to the right of them are a set of rolling drawers for that area (brown top) and the shop crane (red, black).  They've been pushed right about two feet.  That wretched light green thing that moved from right of the benches to sitting in front of the air conditioner is a stationary exercise bike that can be moved across the room should we need to let an A/C repair guy get to the unit on the wall.

Today we pulled out the bench with the computer and micro mill and swapped it with the big mill.  Then we pushed it farther toward the top of the pic and rotated it to get that bench in place along the north wall.  It's closer to both walls than this shows.  The bench with the two lathes still remains to be moved.  The compressor (the blue block, top center) will stay where it is and it's hookup to the Fogbuster cooling system on the back of the mill will be modified. The only machine currently hooked up is the micro mill, and I tested it.  It moves normally. 

I should be able to get the other table with its two lathes into position tomorrow and work toward making the shop fully functional again.  There's more cool stuff that should be happening to go over in the next couple of days. 



Friday, January 8, 2021

Things Are Moving

I just don't have any decent pictures to show what I'm doing.  Let me back up a minute.  

We started down the road of my building a dream shop for retirement in 2013 and broke ground on it in early 2014. As always, no one can predict the future with absolute accuracy so we had no idea that an early retirement offer would change my plans and have me retire after the addition was put on the house but long before the shop was done.  In '14, we had the addition put on the house, with the construction being finished in May and by the end of the year adding the big machines.  Long time readers might remember stories I posted as I converted my milling machine to CNC.

We've been adding household stuff into the room as well as adding tools and accessories all over the shop, but living with the original layout of the shop since the completion of the CNC conversion in 2016. 

As I'm wrapping up the project that has sucked so much time in the last 18 months (!?!), my little IC engine, I've noticed some things I did wrong in the shop layout that have started to annoy me.  I finally decided I wanted to change the layout in the shop, increase storage around the metal shop area, and eventually decided that it needed to be pretty seriously changed.  I had silly little issues like having to walk from the mill halfway through the shop to get a drill bit or a screw.  While I think that stuff about walking 10,000 steps a day is a meaningless number not based on anything, I especially don't want to do it in a couple of hours in the shop. 

The vision when I started was there were to be three shop areas.  One would be machine tools - lathes and mills (there are three and two respectively).  The second area would be for woodworking with a pair of woodworking benches, table saw, router table and hand tools.  The third area would be for reloading, cleaning and working on guns, plus working on fishing tackle, making lures and the very occasional fishing rod.  By necessity, it has morphed into the area where I do much of my battery testing.  (The necessity is that I have nowhere else to set up a computer and monitor.)

In intervening years, the limited woodworking I've done is to build a few sets of shelves that went into the reloading area, and the enclosure for the big milling machine.  There have been a couple of other things, but nothing major. 


The mill in its enclosure when I declared the CNC conversion done and started trying to make things with it.  In the bottom left corner of the picture you see a wooden bench top with a mouse pad on it. 

In the next day or so, the mill enclosure and that work bench, which is paired in an "L" with another bench just like it, will swap places.

Oh, and there's more geekiness to come.



Thursday, January 7, 2021

Eileen Lights Up

Yesterday afternoon, the Starship prototype Eileen had an apparently successful static fire of all three Raptor engines as it moves closer to its first hop.  Potentially this weekend or Monday.


As I say, though, apparently successful.  Teslarati summarized it this way:
SN9 ignited all three of its Raptors in quick succession and shut the engines down over the course of 1.5-2 seconds – extremely short relative to all previous nominal Starhopper or Starship-mounted Raptor static fires. Long-time followers immediately noted that small discrepancy, speculating that it could either have been a post-ignition abort or intentionally shortened to avoid damaging the pad’s concrete surface (an incident that’s occurred several times during recent tests).
It seemed a little short by counting out seconds, which is approximate when I do it, and the test had some unusual aspects to it.  The most unusual thing is that unlike other static fires I've seen, they didn't empty the vehicle and give an "all clear" within an hour or so after the test.  As you can see in the picture, the test was at 4:07 CST (5:07 here).  I went over to the Webcam two hours later to see if anything was going on and saw signs that they might be setting up to do a second static firing.  That never happened and the author at Teslarati implies it might have been because of rain.  They also make clear that none of us know anything official unless SpaceX releases information, typically in a tweet or two from Elon Musk. 

That means the unusual conclusion to this test might have been from troubleshooting some oddity they saw, or a shift to another cryogenic pressure test or something else entirely.  Another piece of evidence arguing something went wrong was that they canceled the road closures for today. 

Two days ago, SpaceX was granted TFRs for flights to unlimited altitude on the 8th - 10th.  From where I sit, I don't think it will launch tomorrow, and if anything was wrong in yesterday's tests I think that lowers the odds that it can launch this weekend at all.



Wednesday, January 6, 2021

The Devil Went Down to Georgia

I'll be honest; I'm having a hard time processing the day.  I could see there being people converging on DC for the Stop The Steal protest, but it went a lot farther than I would think.  If I've heard one person call into one of the talk shows saying they're going to DC, I've heard over half a dozen.  None of them sounded like Antifa.  The stuff captured on the TV news did.  I find Irish collecting lots of things that make it seem like a false flag operation, specifically by Lefties working to make conservatives look bad.


Two months old, same concept. 

A couple of hours ago I'm saying "this smells like a false flag" to Mrs. Graybeard.  While she was watching a video of protesters breaking glass in the capital building she's saying (in concept) the contents of this Tweet that Irish posted.

The situation after Georgia is horrible.  After the enormous fraud in November, why should I believe that this isn't fraud?  After all, Georgia cheated last time, too. 

The chances of getting election reform passed, especially in the Ho Jo administration is zero.  After all, the places that cheated worked very hard to cheat.  They want to keep cheating because cheating = winning.  Anything lawmakers do will be like putting a "Cheat Free Zone" sign over the vote counting offices. 




Tuesday, January 5, 2021

A Set of Predictions for the Year in Space - 2021

A preview of the year to come in space exploration is an annual feature at Ars Technica, and Eric Berger posted this year's version this morning.  He titled it, “There are an insane amount of cool space things happening in 2021” and that's as good a summary as I could hope to do.  As I usually do when I say to go RTWT, I'll excerpt some pieces, starting with what I was thinking of this morning: when are those Mars probes that launched for the opposition going to arrive?
The United Arab Emirates' first mission to the red planet, Mars Hope, is due to arrive on February 9. At this time, the spacecraft will make a challenging maneuver to slow down and enter orbit around Mars with an altitude above the planet as low as 1,000km. If all goes well, the spacecraft will spend a Martian year—687 Earth days—studying the planet's atmosphere and better understanding its weather.

China has not said when, exactly, that its ambitious Tianwen-1 mission will arrive at Mars, but it's expected in mid-February. After the spacecraft enters orbit, it will spend a couple of months preparing to descend to the surface, assessing the planned landing site in the Utopia Planitia region. Then, China will attempt to become only the second country to soft-land a spacecraft on Mars that survives for more than a handful of seconds. It will be a huge moment for the country's space program.

NASA's Mars Perseverance will likely be the last of three missions to arrive at Mars, reaching the red planet in mid-February and attempting a landing in Jezero Crater on February 18. This entry, descent, and landing phase—much like with the Curiosity lander in 2012—will be must-see TV.

History suggests at least one of these three missions will not make it, but we'll hope to defy those odds.
They go on to mention that many Starship tests will take place.  Eileen, on the new test pad over in Boca Chica is up now, with the usual "every date changes" course of action we see.  Today's updates are that residents have been given an over pressure warning for tomorrow.  That implies a minimum of the Wet Dress Rehearsal, and probably static firing.  The FAA granted an unlimited Temporary Flight Restriction for the area, Friday through Sunday, which could be Eileen's flight to 15 km - or higher.

A test flight of the first Super Heavy booster in the first six months of the year is likely, making it almost a sure bet for the whole year.  Berger predicts that's not the only totally unprecedented mission the year will see.  He predicts we'll see one of the most anticipated and most-delayed missions:
Snarking about the delays in the launch schedule of the ultra-ambitious James Webb Space Telescope have become commonplace in the space community, and indeed this flagship astrophysics mission is far behind schedule and over budget.

However, it seems like NASA's current science leadership has addressed a number of the technical and management issues that had been plaguing the telescope program and causing delay after delay. Now, there seems to be quiet confidence that NASA's space telescope will stick to its Oct. 31, 2021 launch date on a European Ariane V rocket.
In addition to Super Heavy, we're likely to see the launch of United Launch Alliance's Vulcan rocket, carrying Astrobotic's Peregrine lander to the Moon.  This one doesn't look good to me; the Vulcan is based on Blue Origin's BE-4 Methane-Oxygen engine, which technically doesn't exist.  Delivery is expected in the summer and launch in the 4th quarter, which is tight considering the amount of newness there.  Other big rockets are possible as well: Japan's H3 booster and Europe's Ariane 6 rocket.  Finally, not a new rocket, but SpaceX has three Falcon Heavy flights on the manifest this year.  Their main emphasis will be recovering all three boosters.  Only one center rocket has landed, and that one later tipped over and fell due to rough seas combined with the lack of hardware to hold it on deck (the Octagrabber on both recovery drone ships now).

This is just a look at a few things that caught my eye.  If you like to follow space exploration, go read


James Webb Space Telescope, rendering for NASA.  The diameter across those 18 hexagonal mirror "tiles" is 6.5 meters or 256 inches.  Intended for Infrared observation, it has nearly three times the aperture of the Hubble Space Telescope.  Lots of details here.



Monday, January 4, 2021

In Other Space News

Virgin Orbit appears to be readying a test flight of their LauncherOne, an air-dropped small satellite lifter.  The tentative launch date is January 10th and the launch is likely to take place out of west coast facilities as did their previous attempt.  The one which ended with the launch vehicle apparently disintegrating soon after release.
LauncherOne is a rare air-launched rocket and is designed to be dropped from a modified Boeing 747 passenger jet (named “Cosmic Girl”).  For a cost of $12 million, LauncherOne will be able to place up to 600 kg (~1300 lb) into low Earth orbit.

Virgin Orbit also wants to develop a tiny third stage that would enable the small rocket to send payloads of 25-50 kg or more to the Moon and beyond.
The mission has bumped into this year after delays from Covid - they're in California - and going through periods when they didn't have enough people to get things done.

After that last loss of vehicle and mission, Peter Beck (Rocket Lab) and Elon Musk (SpaceX) tweeted moral support to the Virgin Orbit team.  "Orbit is hard."



Similarly, startup Firefly Space, has been steadily moving toward the first test of their orbital class rocket, Alpha.  The last time we talked about Firefly Space, last March, they were talking about testing it "this summer" - as in summer of '20.  As you might expect, that was too ambitious.
Firefly's first Alpha booster arrived at its Vandenberg Air Force Base (VAFB) launch pad in November, while Alpha's orbital upper stage wrapped up a qualification static fire in December - shipment to Firefly's California launch pad TBD.

The cause of the delay is unclear but it's not exactly surprising for a new rocket's first launch campaign and a startup's first launch attempt.
Firefly Alpha.



Blue Origin made a show of christening a used cargo ship currently being modified into a seagoing landing platform for the New Glenn's massive boosters.  Since Blue Origin took possession of the ship - formerly known as Stena Freighter - more than two years ago, almost nothing has visibly changed.  The visible changes are the removal of two aft exhaust stacks and renaming the ship Jacklyn after Bezos' mother.  It appears to be nowhere close to ready for New Glenn booster landings. 

Which may not be a problem because the New Glenn appears to be nowhere close to ready to fly.  Aside from two aluminum rings, maybe a fifth of a tank dome, and two "pathfinder" BE-4 engines that are (1) not meant for New Glenn and (2) not meant for flight, Blue Origin has yet to reveal New Glenn flight hardware of any kind. The last real official announcement of the first launch date ("2021") came almost two years ago in January 2019 and is now comically ludicrous with just ~12 months left and zero flight hardware in work.



Meanwhile, the last time we talked about the SLS static firing test, word was they hoped to resume testing this month.  They're close-mouthed about it and no news is available.  I'm trying. 




Sunday, January 3, 2021

About That Small Engine I'm Building

Small?  Tiny?  How does 3/4 cubic inch strike you?  To me, that's closer to tiny than small, but definitely in the range.  3/4 cubic inch is bigger than the tiny model plane engines and smaller than any lawnmower I've owned.  

The short update is that it still doesn't run. A longer update is I haven't tried to run it since finding the fuel bottle destroyed back a bit over two weeks ago.  The parts I need to fix the tank were here by the day after Christmas, much sooner than I expected, but I haven't tried to put gas in the tank and start it yet.

I've been doing other things.  I noted in that linked post that it was time to take that valve stack apart. For openers, it didn't look like the intake valve spring was moving right, so I did something I should have done all along and tapered the valve guide per print.  First the intake and then the exhaust.  Because I didn't think it possible to remove the valve guide from the intake block without ruining the guide, I set up my four jaw chuck on my manual Sherline lathe and used their compound to cut the taper.  


Then I lapped the valves against their valve guides again. This time with the valve stem in the three jaw chuck on the lathe and pulling the block with the valve guide (pictured) against the valve.  I've done more troubleshooting steps trying to convince myself the engine is OK.  

I wanted to make sure the valves would drop freely through the valve guides.  Intake fell, exhaust would bind sometimes.  I made a little valve holder to hold it in lathe chuck, then held 240 followed by 500 sandpaper against as it spun in the lathe.  After this, it fell freely through the valve guide as well. It was time to put it all back together and see if it looked any better qualitatively.

When I ran the flywheel with my starter drill, I didn't see any motion of the intake valve.  I want to see it opening and closing, but I've been told by a couple of guys who have made this engine that it might not be perceptible.  On the other hand, I've seen videos where the intake valve's movement is very obvious.  There's a potential problem with the intake valve spring in that I made it from music wire I had on hand (.015" dia) not what the plans called for (.013" dia). If there are two identical springs made with those wire sizes, the one made with bigger wires is stiffer than the one made with the smaller.  Springs are complicated. The strength comes from the wire diameter, the pitch (turns per inch) and the diameter of the spring. I could have used the wrong wire but made up for it by making too many turns.

Strangely, I have around three feet of .013" wire in the house. It's called the second string in a set of Ernie Ball Slinky guitar strings.  Even stranger, it's cheaper to sacrifice a set of those strings than buy a few more feet of .013" music wire from the usual sources.

I'm just about at an impasse where I don't know what to do.  One possibility is to rewind the intake valve spring.  I have considered sending the whole engine to Hydraulic Press channel on YouTube to let him crush it into a round slab of mixed metals.  A better idea is to back away for a few days.  I could use to clean up and organize a bit better in the shop anyway.




Saturday, January 2, 2021

When Landing Orbital Class Boosters Gets Too Routine...

You can accuse Elon Musk of a lot of things, but something you can't accuse him of is having no vision for the future.  As recently as 2014, NASA dismissed SpaceX's plans to recover Falcon 9 boosters.  Now, SpaceX has recovered so many boosters that they dropped their production rate; they simply don't need as many boosters, even with their launch cadence that's many times anyone else in the business.  As far as NASA and other Fed.gov agencies are concerned, they've dropped their policy of never flying on a recovered booster - even for manned flights.  While I'm still not tired of watching them do it, landing a booster on a drone ship hundreds of miles from any landmark has become routine.

As reported by Teslarati on Thursday, last Wednesday, Musk revealed that their plans for Super Heavy are changing.  Super Heavy, of course, is the booster for the Starships they've been protoyping.  They're considering not putting landing gear on Super Heavy and landing them as we're used to with Falcon 9 and instead catching them with the launch tower.


It's important not to lose track of what we're talking about here.  Super Heavy will be the largest rocket stage ever built – and by a large margin.  It will lift a ~300,000 lb Starship around 25% of the way to orbit, with a liftoff thrust of ~16.2 Million Pounds.  The booster alone will be 70 meters, around 230 feet, tall.  The Apollo Saturn V booster had a liftoff thrust of ~7.5 million pounds.  I don't have any references for what the Super Heavy should weigh when it's ready to be recovered, but the idea is to modify the launch umbilical tower to allow it to catch Super Heavy by its titanium grid fins. 
Launch mount recovery would require unprecedented precision and accuracy and add a new element of risk or a need for extraordinarily sturdy pad hardware. However, the benefits would be equally significant, entirely eliminating the need for expensive recovery assets, time-consuming transport, and even the time it would take to crane Super Heavy boosters back onto the launch mount from a pad-adjacent landing zone.
In a way, Super Heavy has an advantage over the Falcon 9.  When the Falcon is returning to land, at the very last moments, a single Merlin engine can't be throttled back far enough to allow the booster to hover.  They have to adjust the engine to reach zero velocity at zero height, which requires amazingly accurate knowledge of the booster's position in the real world.  The Super Heavy is so much heavier than a Falcon 9 that it can hover. 

Scott Manley does a great presentation on this.


This idea is wild, and full of risk, but could bring a lot of improvements to the Starship. Not having the landing legs will save weight, which moves into the payload. They are, after all, planning on building hundreds of these.


A few weeks ago, Musk tweeted that we should see Super Heavy fly "in a few months."  I don't see any infrastructure in the Boca Chica area that could catch the booster out of the air; I guess they have a few months to build that, too.

This has the potential of being a lot of fun to watch.  Word is they think they've fixed the issue that caused SN8 to crash, so considering how close to total success that was, Eileen's flight should be fun to watch.  I expect that next week (11th to 15th).