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.

Category: Home Ec

Things around the home & hearth

Refrigerator Coil Wand Adapter Rebuild
After five years, the adapter between the Kenmore Progressive vacuum cleaner and the long wand required to reach inside the refrigerator evaporator coils broke at the latch opening:

$Kenmore Vacuum - refrigerator coil adapter - fracture$
Kenmore Vacuum – refrigerator coil adapter – fracture

A quick fix let me continue the mission:

Kenmore Vacuum – refrigerator coil adapter – temporary fix

A better fix required a few minutes of OpenSCAD tweakage and a few hours of hands-off build time:

Refrigerator Coil Wand Adapter – Slic3r preview

The fitting ID is now 2 mm smaller, the 3D honeycomb infill is 25%, and (contrary to the picture) it now has 4 perimeter threads. It’s a two-line change from the last time:
```
OEMTube = [35.0 - 2.0,35.0,41.7,40.5,30.0];           // main fitting tube
… then, inside MaleFitting() …
cylinder(d1=OEMTube[ID2],d2=OEMTube[ID1],h=2*OEMTube[LENGTH] + 2*Protrusion);
```
Those will propagate to anything I build from now on, although this is the first latch fracture.

Gotta love it when 3D printing lives up to the hype!
2020-02-25
HON Lateral File Cabinet Foot Repair

We bought the best-looking (pronounced “least bashed”) pair of hulking five-drawer industrial-strength HON Brigade Lateral File Cabinets from the local ReStore outlet’s assortment for Mary’s quilting fabric stash. They came with a steep discount, barely fit inside the Forester, caused minor interior trim damage, and should organize her entire stash.

One cabinet lost a foot nut at some point in its 16 year history:

HON Lateral File – foot hole – weld nugget filed

The surviving foot nuts sported two weld nuggets apiece:

HON Lateral File – OEM front foot

The hole had the remains of one nugget at the top left and looks like a manufacturing defect to me. Of course, we’re (at least) the second owners and the usual lifetime warranty no longer applies.

I can fix that.

Bandsaw a 1×¾ inch rectangle from 3/8 inch aluminum plate to match the surviving foot nut (which is steel, but aluminum will suffice for our needs). Break the edges, clamp in the Sherline, and mill a square protrusion to match the square-ish hole:

HON Lateral File – square nut – rough cut

Drill a 17/64 inch hole (looser than the nominal F drill, because I’m a sissy) for a flat-head bolt from the Drawer o’ 3/8-16 Bolts, tap, and clean up.

A trial fit showed the nugget had to go before the nut would come even close to fitting flat into the hole:

HON Lateral File – foot hole – grinding

The sheet metal around the hole had absorbed at least one mighty blow pushing the entire surface inward behind the front edge. To compensate, recess the nut’s front edge and slope the sides with a Dremel wheel to let the bottom face sit level:

HON Lateral File – square nut – taper grinding

Another trial fit showed the need for more recess:

HON Lateral File – square nut – deeper cut

Another spate of grinding made it sit mostly level on the decidedly non-level surface around the hole:

HON Lateral File – square nut – ready to install

The beveled corners fit inside the swaged hole corners.

Grind paint / crud off the sheet metal and roughen the surface for good epoxy griptivity:

HON Lateral File – foot hole – ready for install

Stand the cabinet top-side-down to make the bottom level. I wish the basement had one more course of block, but it’s not to be.

Butter the nut with JB Weld epoxy, plunk it in place, apply excess epoxy to make a fillet around the edges, apply duct tape to guy the top of the bolt level-ish, and let it cure:

HON Lateral File – square nut – epoxy curing

After the epoxy stiffened enough to hold its position, remove the bolt, file a crude ¼ inch hex, and saw a screwdriver slot to make it match the other feet:

HON Lateral File – new foot hex head

Not the fanciest job I’ve ever done, but it now behaves just like the other ones and it’s all good. The HON Storage Files FAQ points to a Troubleshooting Guide showing how to level the thing with a hex socket from inside the bottom drawer.

The flat heads on those bolts are basically 25 mm OD steel plates calling for fuzzy felt bumpers on the Sewing Room’s wood floors. When properly leveled, the front will be ⅛ inch higher than the rear. Although they suggest a pencil should roll toward the back, the top sheet metal on this one may be sufficiently warped to confuse the issue; I have a long level well suited to the task.

The original dimension doodle includes metric offsets for cutting with a ¼ inch end mill:

HON Foot nut – dimension doodles

All in all, a satisfying day in the Basement Shop …

2020-02-24
The Return of High-Reliability / High-Availability Trash Cans

Five years ago, robotic trash cans were a thing on Vassar’s campus, including this duo in front of Vassar’s library:

Vassar Library – Trash and recycling containers

That was then, this is now:

Vassar Library trash cans

I infer the robotics did not work out as anticipated.

2020-02-23
Frozen Fire Hydrant, One Year On

It seems reporting a frozen hydrant to the local fire company didn’t produce any meaningful action:

Frozen hydrant – Sheldon at Rt 376

We didn’t have any fires in the neighborhood where it might have been a problem, but I’ll try the water department this year …

Oddly, the water department repainted most of the fire hydrants along most of the roads last year. This one apparently didn’t qualify, for whatever reason, despite being only slightly off Rt 376 on Sheldon:

Frozen hydrant – Sheldon at Rt 376 – Google Streetview

When it’s not frozen, it’s not obvious …

2020-02-22

Bird Box Entrance Reducers: Round 2

One of the bird box entrance reducers I installed nigh onto a decade ago is still on duty, although downy woodpeckers definitely want a larger hole:

Bird Box - gray PVC pipe reducer - woodpecker damage — Bird Box – gray PVC pipe reducer – woodpecker damage

Another reducer had gone missing over the years, so I made one from a length of PVC pipe:

Bird Box - PVC pipe reducer - shaping — Bird Box – PVC pipe reducer – shaping

It started as 1-½ PVC pipe, 1-⅞ inch actual OD and should fit into a 1-½ hole, so I measured 1.5 × 3.15 around the circumference, bandsawed out the excess, draped it over a 1-½ Forstner bit, toasted it with a heat gun, and squashed it so it’s just a little bit bigger than the (enlarged!) hole in the box.

Now the entrance is 1-¼ (-ish), just like it should be:

Bird Box - PVC pipe reducer - installed — Bird Box – PVC pipe reducer – installed

The bird box in the front yard has been attracting starlings, in addition to serving as a hawk perch:

New Coopers Hawks - bird box takeoff whoops — New Coopers Hawks – bird box takeoff whoops

The oblong hole required advanced manufacturing techniques:

The front face should be too slick for larger birds and the little ones will zip right into the hole:

Bird Box - 3D printed entrance reducer — Bird Box – 3D printed entrance reducer

The two starlings who’d been evaluating the box seem to have moved on; we doubt they’re now homeless.

The OpenSCAD source code as a GitHub Gist:

	// Bird Box – oval entrance reducer
	// Ed Nisley KE4ZNU 2020-02-12

	//- Extrusion parameters must match reality!
	// Print with 3 shells and 3 solid layers

	ThreadThick = 0.25;
	ThreadWidth = 0.40;

	HoleWindage = 0.2;

	function IntegerMultiple(Size,Unit) = Unit * ceil(Size / Unit);

	Protrusion = 0.1; // make holes end cleanly

	inch = 25.4;

	//———————-
	// Dimensions

	EntranceID = 1.25 * inch;

	BoxHole = [1.5,2.25] * inch;
	BoxWall = 0.75 * inch;

	HoleOC = BoxHole.y – BoxHole.x;

	FlangeWidth = 5.0;
	FlangeThick = 5*ThreadThick;

	$fn = 12*4;

	//——————-
	// Build it

	difference() {
	union() {
	linear_extrude(height=BoxWall + FlangeThick)
	hull()
	for (j=[-1,1])
	translate([0,j*HoleOC/2])
	circle(d=BoxHole.x);
	linear_extrude(height=FlangeThick)
	hull()
	for (j=[-1,1])
	translate([0,j*HoleOC/2])
	circle(d=BoxHole.x + 2*FlangeWidth);
	}
	translate([0,0,-Protrusion])
	cylinder(d=EntranceID,h=2*BoxWall);
	}

view raw Oval Entrance Reducer.scad hosted with ❤ by GitHub

2020-02-19

Hiatus

Between the ACM presentation, an upcoming Digital Machinist column, and homeowner stuff “not relevant here”, I’ll be posting intermittently for a week or so.

Logo – Isolated 0D3

Algorithmic Artifacts will be getting more attention!

2020-02-07
High-Impact Driving

We spotted this near our usual parking spot during a recent grocery trip:

Adams crash – stone wall

The bush was pretty well uprooted, suggesting the vehicle stopped atop the bush after demolishing the wall.

Wondering how it got there, I looked across the parking lot:

Adams crash – reverse view

Yes, that’s a dead lamp post. The impact dislodged its concrete base by about four inches:

Adams crash – lamp pole detail

The greenery came from another eviscerated bush:

Adams crash – bush debris

I expected to see tire gouges in the grass, but … nope.

The bush got a haircut, although the right half seems undamaged:

Adams crash – bush detail

The boulder won its disagreement with the vehicle, although there’s surprisingly little shattered plastic and other debris along the trail:

Adams crash – boulder detail

The impact dislodged the boulder, which came to rest about four feet from its origin:

Adams crash – overview

The damage lies along a straight line from the middle of the Adams entrance intersection to the wall impact:

Adams crash – trajectory

There are no obvious skid marks, undercarriage scrapes, or gouges in the grass anywhere along the trajectory, suggesting the vehicle remained mostly airborne and ballistic during the whole event, and even the three (!) curbs involved have no marks.

The nice lady at the Adams Customer Service counter didn’t know what happened and, as usual, the Poughkeepsie Journal (newspaper) has nothing to say.

I did not check for a high-clearance pickup truck with tall tires and severe front-end damage in the body shop across the street, although one seems a likely suspect. Whatever the vehicle may have been, it was definitely traveling at the usual (tautological) “high rate of speed” …

2020-02-02