The Smell of Molten Projects in the Morning

Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.

Tag: Improvements

Making the world a better place, one piece at a time

Microscope Stage Positioner: Rigid MakerBeam Edition

Rebuilding the XYZ stage positioner with MakerBeam aluminum struts, but without the steel brackets, produce a much more rigid result:

Microscope Stage Positioner – rigid Makerbeam

This requires drilling holes through the extrusions:

Microscope Stage Positioner – Makerbeam drilling

Running the center drill down until it just nicks the sides produces enough of a pilot hole through the center section to capture the 3 mm drill. If I had to drill enough holes to make a fixture worthwhile, I could probably eliminate the divots.

Two more holes + epoxied M3 brass inserts attached the 60 mm beam directly to the Z Axis stage, thereby eliminating the vertical beam and a steel bracket:

Microscope Stage Positioner – Makerbeam joints

The M3 SHCS attaching the 100 mm beam goes through both beams. I think you could get the same result with a Tee Nut or a 12 mm Square Head bolt, should you have those lying around and don’t want to drill another hole. The Corner Cube screwed into both beams prevents rotation and helps ensure perpendicularity.

The Y stage now attaches directly to the beam, rather than through a pair of Corner Cubes, because I realized I wasn’t ever going to adjust its position.

The Z Axis stage stands on the plastic plate through a hellish mixture of metric and USA-ian screws. Basically, the 6-40 screws into the stage were long enough, the 6-32 screws through the plate fit the existing holes, and M3 screws are for MakerBeam:

Microscope Stage Positioner – Z Axis base

To my utter astonishment, the threads in the end of the vertical beam had the proper alignment to let a Square Head bolt snug the beam against the 40 mm beam on the plate. As a result, the L Bracket just prevents the vertical beam from turning on the screw and the combination is as rigid as you (well, I) could want.

The 40 mm beam has two spurious holes, because I thought I could avoid drilling another hole in the baseplate. Nobody will ever notice.

After squaring and tightening everything, the 100 mm beam along the Y Axis is now horizontal within 0.2 mm and the X Axis is horizontal to better than I can measure.

It’s definitely Good Enough™ for me:

Microscope Stage Positioner – in use

Remember, nothing exceeds like excess …

2021-06-08
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

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

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

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

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

And epoxied 3 mm brass inserts in their place:

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

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

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 …

2021-06-07
Aceco FC1002 Battery Re-replacement

My old Aceco FC1002 frequency meter stopped working without being plugged into the charger. It runs from a quartet of NiMH cells taped into a tray I made seven years ago:

Aceco FC1002 – hacked battery

One of the cells was completely dead and the other three will blink LEDs for the rest of their lives.

The Eneloops have trickled down from the DSC-H5 and still seem perfectly fine for ordinary use.

The faceplate bears the scars of its cracked acrylic (?) coating, so I pushed it out, traced the outline on a flat piece of polypropylene clamshell packaging, cut it out, and stuck it in place with tapeless sticky:

Aceco FC1002 – polypropylene faceplate

That removes the branding, but IMO improves the appearance.

It should continue working for another half decade or so!

2021-06-03
MakerBeam Swarf Cleanout

~~Playing with~~ Evaluating a recently arrived MakerBeam Starter Kit revealed swarf snarls in the tapped end holes. After giving up on a needle-nose tweezer, a compressed air blow gun expelled the mess from a handful of short beams:

Makerbeam – internal swarf A

A scrap of acoustic foam backstopped the rest of the assortment:

Makerbeam – internal swarf B

Which doesn’t account for the scattering of swarf and oil blown elsewhere in the Basement Shop.

Perhaps a bad day in the MakerBeam factory?

Protip: wear eye protection when using compressed air!

2021-06-02
Tour Easy: Rear Fender Bracket Installed

A rainy day finally produced an opportunity to install the rear fender bracket on my bike:

Tour Easy Rear Fender Bracket – improved

It’s actually another iteration, tweaked to hold the fender snugly against the bracket, because it’s tucked in a location where I can’t measure anything.

The brake noodle isn’t connected yet, but it has plenty of room in front of the fender block.

2021-05-31
Bafang Programming Adapter: More Cable Colors

In the process of installing a Bafang BBS02 mid-drive motor on a friend’s diamond-frame bike, I discovered, once again, how little anybody cares about the colors inside cables:

Bafang Display Extension Cable – internal colors

The cheerful rainbow on the right is the stub end of the Bafang display extension cable I built into the previous adapter.

The new cable on the left seemed like it might match the canonical colors:

Bafang BBS02 display cable pinout

It comes heartbreakingly close:

Bafang Display Cable – extension colors

Brown and Orange connect as the naive user might expect, which does reduce the likelihood of incinerating the motor controller / USB adapter / laptop by connecting the 48 V battery directly to the logic-level electronics.

However, White wasn’t on the original menu, Green is now TXD, and Black has become, comfortingly, GND.

Verily, it is written: Hell hath no fury like that of an unjustified assumption.

This socket connector has a watertight shell making it extremely difficult to mate and unmate with the pin connector on the bike. Watertightness being unnecessary, a little razor-knife action seems in order:

Bafang Display Extension Cable – shroud trimming

Visually, they’re both green-ish, but sometimes the Pixel camera accentuates any differences.

2021-05-28
NYS DOT Motivation: Death

We have just started rolling from Overocker Road and the traffic signal on Burnett Blvd at Rt 55 (on the far left) has just turned green for the single car on the sensor loop:

Burnett Blvd Rt 55 – 2021-05-23 – 0 s

Much to our surprise, 17 s later the signal is still green:

Burnett Blvd Rt 55 – 2021-05-23 – 17 s

As usual, the unmarked sensor loop doesn’t detect bicycles and the control doesn’t take our clearing time into account, so the signal turns yellow 5 s later (after 22 s from turning green) while we’re still in the intersection:

Burnett Blvd Rt 55 – 2021-05-23 – 22 sBurnett Blvd Rt 55 – 2021-05-23 – 22 s

After another 6 s, though, we’re through the intersection and lined up on the right side of Rt 55, just as the Rt 55 signal turns green:

Burnett Blvd Rt 55 – 2021-05-23 – 28 s

Note that the Burnett Blvd signal remained green for 22 s, much longer than in bygone years, and the green-to-green time is now 28 s. We got through the intersection without any difficulty, although the green-to-red clearance time remains scanty.

Those of long memory may recall my writeup of the timing in early November last year. That was with many cars triggering the sensor loops, so the timings from a trip last July with a single truck-and-trailer tripping the sensor may be more relevant. Or take your pick from other timings done during the last six years; there’s plenty of data to show something’s new and different.

Mary recently discovered a reason why NYS DOT may have suddenly changed the signal timing at the Burnett intersection after all those years:

During the incident, a black Nissan Titan, driven by a 51-year-old male resident of Lagrangeville, collided with a bicycle, ridden by a 58-year-old male resident of Poughkeepsie, in the area of the crosswalk on the southeast portion of the intersection, said the Town of Poughkeepsie Police.
The bicyclist sustained serious injuries and was transported to MidHudson Regional Hospital.
https://dailyvoice.com/new-york/putnam/police-fire/bicyclist-seriously-injured-after-crash-with-vehicle-in-area/798453/

The crosswalk mentioned in the article appears in the last picture.

The cyclist died of his injuries shortly after that article went live.

Mary knew him. He was one of the gardeners near her plot in the Vassar Community Garden who lived in the apartments a few hundred yards from that intersection, didn’t own a car, and, for years, rode through that intersection to the grocery store at the far end of Burnett Blvd (across another of DOT’s intersections). Everyone knew him as a nice, considerate guy.

When DOT tells you “Clearance times are determined based on speed, intersection dimensions, grade, and reaction time and cannot be adjusted” they don’t add “Because not enough people have died to get our attention.”

Death is the only thing that will convince NYS DOT’s engineers to change the signal timing at an intersection.

As far as I can tell, all of the other intersections along our usual routes still have the same inadequate clearance times. Evidently, the bicyclist death toll isn’t high enough to get their attention and evidence here doesn’t matter there, because motor vehicle traffic cannot be delayed, even for a few seconds, merely to protect the most vulnerable “users” of their facilities.

We’ve been bicycling all our adult lives and haven’t been killed yet, despite NYS DOT’s complete lack of attention. Our experiences justify my cynicism and bitterness.

I eventually figured out why no NYS DOT staffer will accompany me on bike trips along their “safe for all users” roads. If they did, they’d be unable to deny knowing how hazardous their engineering designs & maintenance practices are in real life, should the question come up in a court of law.

If you think that’s not the case, then let’s go riding together …

Road design, build quality, and attention to details matter, even though drivers and, yes, cyclists share some of the blame.

2021-05-24