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.
If you measure something often enough, it becomes science
The turkey hen who once had nine chicks, then seven, now has only two:
We haven’t seen the fox since it nailed the previous chick, but it may be responsible for taking a chick a day, every day, for a week.
We wonder if she misses the rest of her brood as much as we do …
Taken through two layers of 1950s window glass, zoomed all the way in, with a phone camera.
With an outmoded LM12UU linear bearing drag knife mount on hand, I threaded an M4 screw into each brass insert, lined it up on a hole in a homebrew (by a long-gone machinist, not me) steel bench block, and applied pressure with the drill press until the insert tore out:
The retina-burn orange ring is printed in PETG with my usual slicer settings: three perimeter threads, three top and bottom layers, and 15% 3D honeycomb infill. That combination is strong enough and stiff enough for essentially everything I do around here.
The insert on the left came out of its hole carrying its layer of epoxy: the epoxy-to-hole bond failed first. Despite that, punching it out required enough force to convince me it wasn’t going anywhere on its own.
The column of plastic around the insert standing up from the top fits into the central hole (hidden in the picture) in the bench block. Basically, the edge of the hole applied enough shear force to the plastic to break the infill before the epoxy tore free, with me applying enough grunt to the drill press quill handle to suggest I should get a real arbor press if I’m going to keep doing this.
The third insert maintained a similar grip, as seen from the left:
And the right:
The perimeter threads around the hole tore away from the infill, with the surface shearing as the plastic column punched through.
Bottom line: a dab of epoxy anchors an insert far better than the 3D printed structure around it can support!
Homeostasis is a thing:
On the other paw, the eyeballometric trend line since mid-April slopes at -1 lb/month and arrives at just over 150 lb in December, so progress continues apace.
Mary saw a fox trotting behind the garden, gripping a (dead) turkey chick in its jaws, with the hen in hot pursuit. The fox dropped the chick, circled the pine grove, picked up the chick, and departed stage right. The hen eventually led her remaining chicks into the yard, but gathered them underneath while watching for danger:
She settled down for a few minutes:
With the fox safely departed, she released the chicks:
Then they returned to foraging, with one chick trying out its wings:
Two days earlier, she led nine chicks through the yard; we think the fox picked off a chick a day. She lost two more during the next four days, suggesting they rapidly improve their ability to scamper out of harm’s way.
This year’s Northern Star Quilt Guild show in the O’Neill Center at WCSU gave me an opportunity to update last year’s data points, although not quite in the way I expected.
The overview:
The left display is rotting out:
The center display seems undamaged:
The right display took a direct hit:
So the middle station refilled 3025 = 10460 – 7435 bottles, roughly eight bottles a day, every day, for a year. Seems like a lot of refilling, doesn’t it?
Unfortunately, I didn’t take pictures of the other watering hole last year, but here’s what it looks like now:
Overview:
Left:
Center:
Right:
Now, it’s entirely possible I have the two stations reversed, in which case I have numbers for all three displays:
Does a bottle or two a day, every day, for a year, seem more reasonable? Hard to say, so, with a bit of luck, we’ll have more data next year.
For science!
Having reasonable success using a 12 mm hole bored in a 3D printed mount for the nice drag knife holder on the left, I thought I’d try the same trick for the raw aluminum holder on the right side:
The 11.5 mm body is long enough to justify making a longer holder with more bearing surface:
Slicing with four perimeter threads lays down enough reasonably solid plastic to bore the central hole to a nice sliding fit:
The top disk gets bored to a snug press fit around the flange and upper body:
Assemble with springs and it pretty much works:
Unfortunately, it doesn’t work particularly well, because the two screws tightening the MPCNC’s DW660 tool holder (the black band) can apply enough force to deform the PETG mount and lock the drag knife body in the bore, while not being quite tight enough to prevent the mount from moving.
I think the holder for the black knife (on the left) worked better, because:
In any event, I reached a sufficiently happy compromise for some heavy paper / light cardboard test shapes, but a PETG bearing won’t suffice for dependable drag knife cuttery.
Back to the laboratory …
Progress is our most important product:
Now that we’ve begun bicycling more regularly, Winter Bloat is transmogrifying into thigh muscle.
The hills around here become noticeably steeper during winter; we attribute the additional elevation to frost heaves …
The Smell of Molten Projects in the Morning 