Category: Photography & Images

Taking & making images.

Machine Shop, Photography & Images

Microscope Stage Positioner: MakerBeam Rebuild MVP

Over the course of half a decade (!), the 3D printed arm on the XYZ positioner I use with the stereo zoom microscope sagged:

Microscope Stage Positioner - PETG creep angle
Microscope Stage Positioner – PETG creep angle

It’s about what you’d expect from a plastic beam carrying a big lump of brass and steel:

Microscope Stage Positioner
Microscope Stage Positioner

The near side of that arm (the -Y end) drooped about 5 mm below than the side nearest the Z axis slide, so it was time for an update.

Having some MakerBeam ready to hand, this didn’t take long:

Microscope Stage Positioner - Makerbeam overview
Microscope Stage Positioner – Makerbeam overview

Protip: before dismantling a fitted slide, mark one end so you know how to put it back together. Bonus points for taking a picture:

Microscope Stage Positioner - slide marking
Microscope Stage Positioner – slide marking

Double bonus points for writing a blog post.

Rather than fight with the existing fine-pitch USA-ian screws, I drilled out their threaded holes:

Microscope Stage Positioner - Y slide drilling
Microscope Stage Positioner – Y slide drilling

And epoxied 3 mm brass inserts in their place:

Microscope Stage Positioner - Y slide M3 inserts
Microscope Stage Positioner – Y slide M3 inserts

Those holes match up with a pair of corner cubes normally appearing on the end of the beams:

Microscope Stage Positioner - BHCS mods for Makerbeam
Microscope Stage Positioner – BHCS mods for Makerbeam

It turns out M3 button head cap screws will slide into the beams if you file the slightest angle on opposite sides of the button, although a small bag of tiny tee nuts should arrive in a while.

Then a variety of brackets spliced everything together:

Microscope Stage Positioner - Makerbeam detail
Microscope Stage Positioner – Makerbeam detail

Although it looks strictly from industrial, it actually wasn’t much better than the plastic edition and, in fact, the beam supporting the XY slides sagged about the same 5 mm. The plastic upright post also contributed a bit of wobble.

It turns out that the extruded aluminum beams have plenty of longitudinal and torsional stiffness, but all those flat steel fittings don’t.

There’s a way to work with the beam strengths, rather than against them, but that’s a story for another day …

Photography & Images

A New Rabbit Appears

Mary chased a small rabbit out of her garden a few days ago, whereupon we up-armored a few vulnerable parts of the fence. The culprit turns out to be insufferably cute:

Young Rabbit - at the gate
Young Rabbit – at the gate

You cannot be annoyed with something like this:

Young Rabbit - alert
Young Rabbit – alert

Oh, yes, you can. Rabbits are basically eating machines:

Young Rabbit - grazing
Young Rabbit – grazing

They’re welcome to all the greenery in the yard, just nothing in the garden:

Young Rabbit - overcompressed A
Young Rabbit – overcompressed A

It’s known as a 2×2 Bunny, because it can fit through that size opening in a chain link fence while traveling at a dead run.

This one has yet to learn about being wary around the Big People:

Young Rabbit - overcompressed B
Young Rabbit – overcompressed B

The alert reader will have noted the crappy quality of the last three pictures, at least in comparison with the first two. It’s the difference between digital zoom on my Pixel 3a phone applied to a zoomed-all-the-way image and optical zoom on a “real” camera (admittedly, an old Sony DSC-H5). On the other paw, I had the phone in my pocket when Mary spotted the bunny on the driveway, which counts for everything in similar situations.

JPG compression doesn’t handle hair particularly well, so the low-res bunny wears a rather artistic brush-stroke coat; it’s OK if you like that sort of thing.

Machine Shop, Photography & Images, Recumbent Bicycling

Bicycle Helmet Mirror: Stalk Repair

The mirror on my bike helmet snagged on a mesh fence while walking the bike to Mary’s garden:

Helmet Mirror - bent stalk
Helmet Mirror – bent stalk

One of the good things about building your own stuff is that you have all the parts when something breaks:

Helmet Mirror - damaged parts
Helmet Mirror – damaged parts

The decorative M2 screw and insert pulled out of the ball. The rim of the nail set punch (intruding from the top) just barely caught the edge of the stub inside the ball, so a few taps could extract it. A Dremel cutoff wheel peeled the crumpled end off the stalk.

Reassembly proceeded without incident:

Helmet Mirror - installed
Helmet Mirror – installed

The bizarrely blurred mirror over on the left comes from the Pixel phone camera app deciding this was a Portrait, applying a background blur, and running into trouble with those hard edges in the foreground. The camera app has a distinct Portrait mode that, perhaps, I inadvertently engaged while fumbling around.

Photography & Images, Recumbent Bicycling

Another Nice Doggy

We’re riding southbound on the recently opened section of the Empire State Trail, just south of Hopewell Junction, and are approaching a dog walker totally face-sucked by her phone in the middle of the path:

Empire State Trail - Dog Lunge - 2021-05-12 - 0
Empire State Trail – Dog Lunge – 2021-05-12 – 0

Mary has been dinging her bike bell for the last few seconds and finally manages to break through:

Empire State Trail - Dog Lunge - 2021-05-12 - 1
Empire State Trail – Dog Lunge – 2021-05-12 – 1

The dog walker leans against the fence while pulling on the leash as hard as she can, as if she knows the dog poses a threat:

Empire State Trail - Dog Lunge - 2021-05-12 - 2
Empire State Trail – Dog Lunge – 2021-05-12 – 2

Which it does:

Empire State Trail - Dog Lunge - 2021-05-12 - 3
Empire State Trail – Dog Lunge – 2021-05-12 – 3

The leash is too long for close-quarters work:

Empire State Trail - Dog Lunge - 2021-05-12 - 4
Empire State Trail – Dog Lunge – 2021-05-12 – 4

Nice teeth, doggie:

Empire State Trail - Dog Lunge - 2021-05-12 - 5
Empire State Trail – Dog Lunge – 2021-05-12 – 5

Surely, the dog just wants to lick me to death:

Empire State Trail - Dog Lunge - 2021-05-12 - 6
Empire State Trail – Dog Lunge – 2021-05-12 – 6

Tell me again how well-trained this dog is:

Empire State Trail - Dog Lunge - 2021-05-12 - 7
Empire State Trail – Dog Lunge – 2021-05-12 – 7

Seven seconds after the first picture:

Empire State Trail - Dog Lunge - 2021-05-12 - 8
Empire State Trail – Dog Lunge – 2021-05-12 – 8

The dog also lunged at the pair of bicyclists following us, so perhaps this is how she makes sure it get its exercise during the walk.

I hate dogs.

Oddities, Photography & Images, Science

Vultures Sunning

Spotted after pre-season prep at Mary’s Vassar Farms garden:

Vultures sunning
Vultures sunning

It must feel really good up there atop the old barn, even if they’re sunning themselves to kill off parasites.

Taken with the Pixel 3a zoomed all the way in at 7× from a bit over 200 feet:

Vultures sunning - photo range
Vultures sunning – photo range

Then cropped and sharpened just a smidge. Not a great picture, but good enough for practical purposes; the Good Camera + Big Glass takes better pix and is too awkward to carry in my pocket.

Electronics Workbench, Home Ec, Photography & Images

Fuvaly Bucked Lithium AA Cells

Behold lithium battery technology, a USB charger, and a buck voltage converter mashed into an AA alkaline package:

Fuvaly Bucked Lithium AA - label
Fuvaly Bucked Lithium AA – label

Those are two of a quartet bought from a randomly named Amazon seller to appease my ancient venerable classic Sony DSC-H5’s need for more voltage than new and freshly charged NiMH AA cells can provide for more than a few tens of minutes.

The label claims 1500 mA·h, not the 1120 mA·h I measured:

Fuvaly Bucked Li AA - mAh - 2021-02
Fuvaly Bucked Li AA – mAh – 2021-02

My numbers would be higher with a load less than 500 mA. I doubt the 2.5 A maximum current rating.

The claim of 2.25 W·h is rather optimistic:

Fuvaly Bucked Li AA - 2021-02
Fuvaly Bucked Li AA – 2021-02

Back of the envelope: 2.25 W·h at 1.5 V equals 1.5 A·h, all right. If you squint carefully, though, the output voltages run around 1.4 V, some of which is surely IR drop in my battery holder & test wiring, but it still knocks nearly 10% off the wattage and doesn’t seem to add to the runtime.

The camera’s battery charge indicator will obviously show Full right up until it shuts off, but I’ve always carried a spare pair of cells in my pocket anyway.

Recharging them with a USB meter in series required 425 to 600 mA·h at about 4.8 V, so about 2.5 W·h.

Enlarging the instructions from the back of the box, should they become useful:

Fuvaly Bucked Lithium AA - Instructions
Fuvaly Bucked Lithium AA – Instructions

Nowhere does the package mention the “brand name”, manufacturer, specifications, or much of anything substantial. I suppose anybody selling white-label products appreciates this level of detail.