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.

Author: Ed

Bafang Triangle Plate Rework

The time has come to add a Bafang mid-drive motor to my Tour Easy recumbent, much like the one Mary has been using for the last two years. When I got to the point of installing the motor in the bottom bracket shell, this happened:

Bafang Triangle Plate – jammed screw

It turns out the triangle plate has slightly misplaced bolt holes:

Bafang Triangle Plate – misplaced bolt holes

If you look very carefully, you’ll see the holes sit just slightly above the midline of those ears. The additional fractional millimeter below the holes touches the motor end bell and prevents them from lining up with the tapped holes.

Normally, you’d just hit the plate with a file and be done with it, but it’s ferociously hardened steel: a file bounces right off.

I deployed a Dremel sanding drum above the ShopVac’s snout to catch the abrasive dust, eroded just enough steel to line up the holes, and everything now fits the way it should.

Done!

2023-03-03
Refresh Tears Eye Lube Storage Boxes

A recent Squidwrench meeting provided the opportunity to make a couple of racks for an assortment of Refresh Tears / Liquigel bottles:

Refresh eye lube – storage cases

I used chipboard to find out if the cross plates would stiffen the floppy 1.1 mm sheets enough for this light duty. Indeed, the overall structure becomes a nice rigid box, even though the feet and corners can’t withstand much abuse.

The finger joints use the default settings, which produce a lot of fingers along the edges. This turns out to be a Good Thing, as it gave the yellow wood glue plenty of opportunities to bond the sheets together.

Combining the default 5° slope with nine bottles along each level wastes a tremendous amount of vertical space. The adjacent racks hold three much larger cans per level, so roughly the same space doesn’t look like much. In retrospect, a 3° slope should work for smaller bottles.

And, yes, the squash on the lower shelf store nicely and become yummy meals all winter long.

The overstuffed URL generating the patterns:

http://festi.info/boxes.py/CanStorage?FingerJoint_angle=90.0&FingerJoint_style=rectangular&FingerJoint_surroundingspaces=0.0&FingerJoint_bottom_lip=0.0&FingerJoint_edge_width=1.0&FingerJoint_extra_length=0.0&FingerJoint_finger=2.0&FingerJoint_play=0.0&FingerJoint_space=2.0&FingerJoint_width=1.0&Stackable_angle=60&Stackable_bottom_stabilizers=0.0&Stackable_height=2.0&Stackable_holedistance=1.0&Stackable_width=4.0&fillHoles_bar_length=50&fillHoles_fill_pattern=no+fill&fillHoles_hole_max_radius=3.0&fillHoles_hole_min_radius=0.5&fillHoles_hole_style=round&fillHoles_max_random=1000&fillHoles_space_between_holes=4.0&fillHoles_space_to_border=4.0&top_edge=%C5%A0&bottom_edge=%C5%A1&canDiameter=30&canHeight=75&canNum=18&chuteAngle=5.0&thickness=1.15&format=lbrn2&tabs=0.0&qr_code=0&debug=0&labels=0&reference=0&inner_corners=corner&burn=0.04&language=en

And the eyeburning QR code:

Refresh Eye Lube – chipboard QR code

2023-03-02
Bobbin Storage Trays

Long ago, I gave Mary a box of 100 empty bobbins for her Kenmore 158 sewing machine, with the intent she would never again have to unwind a bobbin to put new thread on it. This worked so well I did the same thing for her Juki, with the result she needed somewhere to store all those filled bobbins.

Her work table has a shallow drawer, so we tried this out:

Bobbin Storage Case – installed

They’re a matched set cut from 1.5 mm TroCraft Eco:

Bobbin Storage Case – cutting overview

Watching all those little rectangles fall out just never gets old:

Bobbin Storage Case – cutting detail

I ran off a test tray in ordinary chipboard that works just as well, but lacks the pleasant appearance and feel of the TroCraft. Clear 1.5 mm acrylic would probably work, at the cost of requring a much neater glue job where the dividers meet the walls.

The spacing is a bit tight to pluck a bobbin from its slot between two others, but now she has enough space to arrange them as needed, with empty spaces around the most-used colors. I offered to carpet the drawer with bobbin trays, but she suggested waiting until these fill up.

The well-stuffed URL specifying the tray:

http://festi.info/boxes.py/TypeTray?FingerJoint_angle=90.0&FingerJoint_style=rectangular&FingerJoint_surroundingspaces=0.5&FingerJoint_bottom_lip=0.0&FingerJoint_edge_width=1.0&FingerJoint_extra_length=0.0&FingerJoint_finger=2.0&FingerJoint_play=0.0&FingerJoint_space=2.0&FingerJoint_width=1.0&Stackable_angle=60&Stackable_bottom_stabilizers=0.0&Stackable_height=2.0&Stackable_holedistance=2.0&Stackable_width=4.0&Hinge_grip_percentage=0&Hinge_outset=0&Hinge_pinwidth=0.5&Hinge_style=outset&Hinge_axle=2.0&Hinge_grip_length=0&Hinge_hingestrength=1&CabinetHinge_bore=3.2&CabinetHinge_eyes_per_hinge=5&CabinetHinge_hinges=2&CabinetHinge_style=inside&CabinetHinge_eye=1.5&CabinetHinge_play=0.05&CabinetHinge_spacing=2.0&Lid_angle=90.0&Lid_hole_width=0&Lid_second_pin=0&Lid_second_pin=1&Lid_spring=both&Lid_style=rectangular&Lid_surroundingspaces=2.0&Lid_bottom_lip=0.0&Lid_edge_width=1.0&Lid_extra_length=0.0&Lid_finger=3.0&Lid_play=0.05&Lid_space=2.0&Lid_width=1.0&Click_angle=5.0&Click_bottom_radius=0.1&Click_depth=3.0&RoundedTriangleEdge_height=50.0&RoundedTriangleEdge_r_hole=2.0&RoundedTriangleEdge_radius=30.0&RoundedTriangleEdge_outset=1.0&Mounting_d_head=6.5&Mounting_d_shaft=3.0&Mounting_margin=0.125&Mounting_num=2&Mounting_side=back&Mounting_style=straight+edge%2C+within&HandleEdge_height=20.0&HandleEdge_hole_height=75.0&HandleEdge_hole_width=40%3A40&HandleEdge_on_sides=0&HandleEdge_on_sides=1&HandleEdge_radius=10.0&HandleEdge_outset=1.0&sx=21*7&sy=12*7&h=20.0&hi=10.0&outside=0&bottom_edge=s&top_edge=S&back_height=0.0&radius=0.0&gripheight=30&gripwidth=00&handle=0&thickness=1.65&format=lbrn2&tabs=0&debug=0&labels=0&reference=00&inner_corners=corner&burn=0.04

Which can now be specified as the biggest QR code I’ve ever seen:

Bobbin Tray – TroCraft Eco QR code

That makes my eyes hurt …

2023-03-01
Grand Prize User Interface FAIL

Found in an apartment building lobby:

Apartment lobby call box

The LCD gibberish comes from an interaction with the camera shutter. It scrolls a lengthy set of instructions, but the peeling labels demonstrate ain’t nobody got time for that.

You were supposed to figure out how to use this thing with no instructions other than the scrolling display. In particular, the multi-multi-function keypad has no labels.

I suspect most folks just haul out their phones and call the tenant.

2023-02-28
Laser-Cut Envelope Opener

As practice in using the laser to engrave a figure to a known depth, this seemed appropriate:

Envelope Opener – original

The black envelope opener on the right came in a long-ago surplus deal and worked really well, which I cannot say for the retail replacements I got a few years back.

The tan envelope opener on the left is an obvious case of IP theft, copying the size and shape using a scanned image:

Classic opener – knife blades – scan

The two blades seemed like good candidates, with the lower one winning the contest:

Kobalt 78010 Mini Utility Knife Blade mask

Although the pack of “mini utility knife blades” sports a Lowe’s Kobalt part number, they no longer carry that item. You can find plenty of identical blades elsewhere, so they’re not a rare collectible and I have plenty of backup.

Put the outline of the opener on a cut layer, put the blade on an engraving layer, orient appropriately, and make a mirror-image duplicate:

Envelope Opener – LB Layout

The original opener is a touch over 3 mm thick, so the settings engrave 0.25 mm into the surface to make a blade pocket, then cut the shapes from 1.5 mm TroCraft Eco:

Envelope Opener – cutting

After all the cutting was done, it looks about as you’d expect:

Envelope Opener – interior layout

Slather with yellow PVA wood glue and apply too many clamps:

Envelope Opener – clamping

Next time around, I’ll round off the edges before assembly, but that’s in the nature of fine tuning:

Envelope Opener – detail

The TroCraft sheet engraves so cleanly that, were I to go into mass production, I’d set up a fixture for grayscale engraving shaping the perimeters.

Obviously, this makes no economic sense, but it does produce a considerable amount of satisfaction, which is pretty much all that matters for such things.

2023-02-27
Tree vs. Guide Rail: Sheared Bolt

Spotted on a walk along the Mighty Wappingers Creek after a storm with plenty of gusty winds:

Tree-smashed guide rail

The tangle of branches and logs came from a tree that fell across the road from the far right side and put that crease into the guide rail. The vertical stump seems unrelated to that incident.

A bit of rummaging at the base of one post produced a victim:

Tree-smashed guide rail – sheared bolt – side

The impact produced enough force to turn the rail brackets into guillotine metal shears against the posts:

Tree-smashed guide rail – sheared bolt – end

It’s not a clean shear cut, which isn’t surprising under the circumstances.

An ordinary ½-13 Grade 8 bolt has a 17 k pound proof load: popping that bolt required a mighty oomf.

Memo to Self: stay indoors during windy storms!

2023-02-24
OMTech 60 W Laser Power Supplies
A LightBurn forum discussion about laser power supplies prompted me to finally organize my pictures.

Without looking at the captions, match each of the following pictures with its description:
- a failed ZYE MYJG60W-Y-1 (came with OMTech laser)
- an unbranded MYJG60W replacement from OMTech
- a Cloudray M60 (bought as a backup)
HV Power Supply – ZYE MYJG60W-Y-1 – failed

HV Power Supply – unbranded MYJG60W

HV Power Supply – Cloudray M60

That was easy, wasn’t it?

As I said in the forum:

My guess is there’s only one ZYE factory (or a dozen clones) producing all the power supplies, then applying whatever sticker the order calls for on the case before dropping it in the carton.

Perhaps Cloudray buys more quality control than the anonymous “brands”, but I wouldn’t lay much money on finding more than two QC bins at the end of the assembly line: either it runs or it doesn’t.
2023-02-23