Repairs – Page 103 – The Smell of Molten Projects in the Morning

Cast Iron Pan Seasoning

The motivation for stripping our cast iron pans:

Wagner cast iron skillet - before - top — Wagner cast iron skillet – before – top

The bottom, of course, carried a heavier layer of crust:

Wagner cast iron skillet - before - bottom — Wagner cast iron skillet – before – bottom

The wet areas came from the usual after-breakfast washing.

Looking down into the electrolytic stripping bath, with bubbles forming on exposed metal areas around the crust on the bottom of the pan:

Wagner cast iron skillet - in stripping bath — Wagner cast iron skillet – in stripping bath

After a day of electrolysis, all the crust was gone. Low labor, low danger, no fuss, not much muss.

Given three stripped pans, the seasoning process involved wiping them with flaxseed oil, baking at 500 °F for an hour, cooling for two hours, and repeating. Six iterations occupied a long day, uncomfortably warmed the kitchen during a long hot summer day, and turned out to be just fussy enough to fit around some short-attention-span projects.

Fast forward one day.

The outside of the seasoned pans looks lovely:

Wagner cast iron skillet - after - bottom — Wagner cast iron skillet – after – bottom

I’d have been hard-pressed to pick out the “Wagner Ware” before stripping the pan.

The inside of all three pans had a peculiar mottled appearance:

Wagner cast iron skillet - after - top — Wagner cast iron skillet – after – top

The medium pan:

Medium cast iron pan - after - top — Medium cast iron pan – after – top

The small pan:

Small cast iron pan - after - top — Small cast iron pan – after – top

The dark spots might suggest I used too much oil and it puddled / collected / whatever while baking, except that I’d slathered the oil on using a scrap from a cotton towel (actually, many scraps, one per iteration), then wiped it off with more towel scraps before baking the pans.

Protip: You’ll eventually have a pile of cotton rags soaked in a drying oil similar to linseed oil. Woodworkers will tell you to wet oily rags with water before sealing them in a plastic bag, because the “drying” process is exothermic: oil-soaked rags can get hot enough for spontaneous combustion. Make it so.

Breakfast proceeded pretty much as usual and the giant omelet (5 eggs, lots of chopped chard, two finely chopped bacon rashers, cheddar cheese, plenty of oil, stuff like that) seemed to stick somewhat less than usual: it’s not a Teflon-coated pan, but worked pretty well.

I did the usual post-breakfast KP, which involves washing the pan with ordinary dish soap, scuffing the recalcitrant bits, and dropping the pan in the dish drainer. I don’t scour the pans, but I don’t treat them with fawning obeisance, either; they’re utensils, not sacred objects.

Just before lunch, this appeared:

Wagner cast iron skillet - washed - top — Wagner cast iron skillet – washed – top

The bottom sported similar rust spots:

Wagner cast iron skillet - washed - bottom — Wagner cast iron skillet – washed – bottom

So that suggests I didn’t apply enough oil. Or scrubbed too hard. Or did something utterly wrong.

Haven’t a clue about what happened. If I didn’t follow the seasoning process, I don’t know what I’d change. Ditto for washing up; it’s not like we haven’t been using the pan for decades.

After supper, I washed & dried the pan, slathered on a generous oil coating, and let it sit, all in the hope the oil eventually forms a good crusty layer.

By and large, the pan works better than it did before and the seasoning not nearly as well as I expected.

2016-09-12

Taylor Kitchen Thermometer Dial Cover

Fortunately, it didn’t fall off into the roasting pan:

Taylor meat thermometer - cover failure — Taylor meat thermometer – cover failure

The lens slides right out of that nicely curved and crimped housing, the rim ID of which should be slightly smaller than the lens OD. But it ain’t and I definitely can’t crimp it any further.

Three small dabs of clear epoxy and it should be good forever more…

It’s a simpler replacement for the digital thermometer, when continuous monitoring isn’t needed. I thought it’d be more durable, but … no.

2016-09-11

Cast Iron Pan Electrolysis Stripping

Our cast iron pans need seasoning, so I decided to start with full-metal-jacket electrolysis stripping, rather than soaking them in oven cleaner / smogging the kitchen with the self-cleaning oven / actually doing any work. The electrolysis setup involves the big battery charger and a bucket of sodium carbonate solution:

Cast iron pan electrolysis - setup — Cast iron pan electrolysis – setup

Although the charger has a 40 A capacity, the small pan bubbles along merrily at a self-limited 7 A:

Cast iron pan electrolysis - bucket — Cast iron pan electrolysis – bucket

The anode is a big sheet of steel that was once an EMI shield in a big PC case. The side facing the pan corroded very quickly, but the outside remains in good shape and I think it’ll suffice for the medium and large pans.

After two hours, only the crustiest bits of the crust remained:

Cast iron pan electrolysis - 2 hours — Cast iron pan electrolysis – 2 hours

Those flakes fell right off after a few pokes from my demolition scraper; definite anticlimax, that.

Another hour in the tank cleaned the handle and removed a few other spots; it now sports a layer of flash rust that’ll require another pass after I strip the other two pans…

2016-09-05

Miniblind Cord Caps

After smashing one of the cord pulls between the sash and the frame:

The glittery PETG looks surprisingly good in the sunlight that will eventually change it into dullness. The black flecks come from optical effects in the plastic, not the usual burned PETG snot.

The solid model is basically a hull around two “spheres”, truncated on top & bottom:

Miniblind cord cap - solid model — Miniblind cord cap – solid model

The interior has a taper to accommodate the knot, but they’re chunky little gadgets:

Miniblind cord cap - solid model - bottom — Miniblind cord cap – solid model – bottom

I thought the facets came out nicely, even if they’re mostly invisible in the picture.

Each pull should build separately to improve the surface finish, so I arranged five copies in sequence from front to back:

Miniblind cord cap - 5 sequential - Slic3r preview — Miniblind cord cap – 5 sequential – Slic3r preview

If you’re using an M2, the fans hanging off the front of the filament drive housing might come a bit too close for comfort, so rotate ’em upward and out of the way.

If you remove the interior features and flip ’em upside down, they’d work well in Spiral Vase mode. You’d have to manually drill the top hole, though, because a hole through the model produces two shells.

The OpenSCAD source code as a GitHub Gist:

	// Cap for miniblind cord
	// Ed Nisley KE4ZNU – August 2016

	//- Extrusion parameters – must match reality!

	ThreadThick = 0.25;
	ThreadWidth = 0.40;

	Protrusion = 0.1;

	HoleWindage = 0.2;

	//——
	// Dimensions

	OD1 = 0;
	OD2 = 1;
	LENGTH = 2;

	Cap = [9.0,16.0,25.0];

	Cord = [2.5,7.0,Cap[LENGTH] – 5];

	NumSides = 8;

	//———————-
	//- Build it

	difference() {

	hull() { // overall shape
	translate([0,0,Cap[LENGTH] – Cap[OD1]/2])
	sphere(d=Cap[OD1],$fn=NumSides);
	translate([0,0,0.5*Cap[OD2]/2])
	sphere(d=Cap[OD2],$fn=2*NumSides); // round the bottom just a bit
	}

	translate([0,0,-Cap[LENGTH]/2]) // trim bottom
	cube([2Cap[OD2],2Cap[OD2],Cap[LENGTH]],center=true);

	translate([0,0,Cap[LENGTH] + 0.8*Cap[OD1]]) // trim top (arbitrarily)
	cube([2Cap[OD1],2Cap[OD1],2*Cap[OD1]],center=true);

	translate([0,0,-Protrusion])
	cylinder(d=Cord[OD1],h=(Cap[LENGTH] + 2*Protrusion),$fn=NumSides);

	translate([0,0,-Protrusion])
	cylinder(d1=Cord[OD2],d2=Cord[OD1],h=(Cord[LENGTH] + Protrusion),$fn=NumSides);
	}

view raw Miniblind cord cap.scad hosted with ❤ by GitHub

2016-09-03

Epson R380 Printer: Resetting the Waste Ink Counter Again

The Epson R380 printer never gets turned off, so it rarely has a chance to complain. After a powerdown due to refreshing the UPS batteries, it lit up with the dreaded “Service required. Visit your friendly Epson repair center” message that indicates you should just throw the printer out, because replacing the internal ink absorber mats / draining the internal tank is, mmm, economically infeasible when you pay somebody else to do it.

Having done this before, though, it’s almost easy…

Pop a PC with a Windows partition off the to-be-recycled stack
Boot System Rescue CD
Back up the partition to a junk hard drive, just for practice
Copy the subdirectory of sketchy utilities to the Windows drive
Boot Windows (with no network connection)
Run sketchy utility to reset the ink counter
Boot SRC, restore partition
Return hard drive & PC to their respective piles
Declare victory and move on

This time, a sketchy utility that resembled the Official Epson Reset Program actually reset something and the printer started up normally. As before, however, the saved MBR didn’t match the on-disk MBR, suggesting that either I don’t understand how to save / restore the MBR or that something once again meddled with the MBR in between the backup and the restore.

I’ve emptied the waste ink tank maybe three times since the last reset: plenty of ink down the drain. Fortunately, I loves me some good continuous-flow ink supply action…

Sheesh & similar remarks.

2016-08-30

Kenmore Progressive Vacuum Tool Adapters: First Failure

I picked up a horsehair dust brush from eBay as a lightweight substitute for the Electrolux aluminum ball, discovered that an adapter I’d already made fit perfectly, did the happy dance, and printed one for the brush. That worked perfectly for half a year, whereupon:

Dust Brush Adapter - broken parts — Dust Brush Adapter – broken parts

It broke about where I expected, along the layer lines at the cross section where the snout joins the fitting. You can see the three perimeter shells I hoped would strengthen the part:

Dust Brush Adapter - layer separation — Dust Brush Adapter – layer separation

That has the usual 15% 3D Honeycomb infill, although there’s not a lot area for infill.

There’s obviously a stress concentration there and making the wall somewhat thicker (to get more plastic-to-plastic area) might suffice. I’m not convinced the layer bonding would be good enough, even with more wall area, to resist the stress; that’s pretty much a textbook example of how & where 3D printed parts fail.

That cross section should look like this:

Dust Brush Adapter - Snout infill - Slic3r preview — Dust Brush Adapter – Snout infill – Slic3r preview

Anyhow, I buttered the snout’s broken end with JB Kwik epoxy, aligned the parts, and clamped them overnight:

Dust Brush Adapter - clamping — Dust Brush Adapter – clamping

The source code now has a separate solid model for the dust brush featuring a slightly shorter snout; if when the epoxy fails, we’ll see how that changes the results. I could add ribs and suchlike along the outside, none of which seem worth the effort right now. Fairing the joint between those two straight sections would achieve the same end, with even more effort, because OpenSCAD.

The OpenSCAD source code as a GitHub Gist:

	// Kenmore vacuum cleaner nozzle adapters
	// Ed Nisley KE4ZNU August 2016

	// Layout options

	Layout = "DustBrush"; // MaleFitting CoilWand FloorBrush CreviceTool ScrubbyTool LuxBrush DustBrush

	//- Extrusion parameters must match reality!
	// Print with +1 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

	//———————-
	// Dimensions

	ID1 = 0; // for tapered tubes
	ID2 = 1;
	OD1 = 2;
	OD2 = 3;
	LENGTH = 4;

	OEMTube = [35.0,35.0,41.7,40.5,30.0]; // main fitting tube
	EndStop = [OEMTube[ID1],OEMTube[ID2],47.5,47.5,6.5]; // flange at end of main tube

	FittingOAL = OEMTube[LENGTH] + EndStop[LENGTH];

	$fn = 12*4;

	//———————-
	// Useful routines

	module PolyCyl(Dia,Height,ForceSides=0) { // based on nophead's polyholes

	Sides = (ForceSides != 0) ? ForceSides : (ceil(Dia) + 2);
	FixDia = Dia / cos(180/Sides);
	cylinder(r=(FixDia + HoleWindage)/2,h=Height,$fn=Sides);
	}


	//——————-
	// Male fitting on end of Kenmore tools
	// This slides into the end of the handle or wand and latches firmly in place

	module MaleFitting() {

	Latch = [40,11.5,5.0]; // rectangle latch opening
	EntryAngle = 45; // latch entry ramp
	EntrySides = 16;
	EntryHeight = 15.0; // lower edge on inside of fitting

	KeyRadius = 1.0;

	translate([0,0,6.5])
	difference() {
	union() {
	cylinder(d1=OEMTube[OD1],d2=OEMTube[OD2],h=OEMTube[LENGTH]); // main tube

	hull() // insertion guide
	for (i=[-(6.0/2 – KeyRadius),(6.0/2 – KeyRadius)],
	j=[-(28.0/2 – KeyRadius),(28.0/2 – KeyRadius)],
	k=[-(26.0/2 – KeyRadius),(26.0/2 – KeyRadius)])
	translate([(i – (OEMTube[ID1]/2 + OEMTube[OD1]/2)/2 + 6.0/2),j,(k + 26.0/2 – 1.0)])
	sphere(r=KeyRadius,$fn=8);

	translate([0,0,-EndStop[LENGTH]]) // wand tube butts against this
	cylinder(d=EndStop[OD1],h=EndStop[LENGTH] + Protrusion);
	}

	translate([0,0,-OEMTube[LENGTH]]) // main bore
	cylinder(d=OEMTube[ID1],h=2OEMTube[LENGTH] + 2Protrusion);

	translate([0,-11.5/2,23.0 – 5.0]) // latch opening
	cube(Latch);

	translate([OEMTube[ID1]/2 + EntryHeight/tan(90-EntryAngle),0,0]) // latch ramp
	translate([(Latch[1]/cos(180/EntrySides))cos(EntryAngle)/2,0,(Latch[1]/cos(180/EntrySides))sin(EntryAngle)/2])
	rotate([0,-EntryAngle,0])
	intersection() {
	rotate(180/EntrySides)
	PolyCyl(Latch[1],Latch[0],EntrySides);
	translate([-(2*Latch[0])/2,0,-Protrusion])
	cube(2*Latch[0],center=true);
	}
	}
	}

	//——————-
	// Refrigerator evaporator coil wand

	module CoilWand() {

	union() {
	translate([0,0,50.0])
	rotate([180,0,0])
	difference() {
	cylinder(d1=EndStop[OD1],d2=42.0,h=50.0);
	translate([0,0,-Protrusion])
	cylinder(d1=35.0,d2=35.8,h=100);
	}
	translate([0,0,50.0 – Protrusion])
	MaleFitting();
	}
	}


	//——————-
	// Samsung floor brush

	module FloorBrush() {

	union() {
	translate([0,0,60.0])
	rotate([180,0,0])
	difference() {
	union() {
	cylinder(d1=EndStop[OD1],d2=32.4,h=10.0);
	translate([0,0,10.0 – Protrusion])
	cylinder(d1=32.4,d2=30.7,h=50.0 + Protrusion);
	}
	translate([0,0,-Protrusion])
	cylinder(d1=28.0,d2=24.0,h=100);
	}
	translate([0,0,60.0 – Protrusion])
	MaleFitting();
	}
	}


	//——————-
	// Crevice tool

	module CreviceTool() {

	union() {
	translate([0,0,60.0])
	rotate([180,0,0])
	difference() {
	union() {
	cylinder(d1=EndStop[OD1],d2=32.0,h=10.0);
	translate([0,0,10.0 – Protrusion])
	cylinder(d1=32.0,d2=30.4,h=50.0 + Protrusion);
	}
	translate([0,0,-Protrusion])
	cylinder(d1=28.0,d2=24.0,h=100);
	}
	translate([0,0,60.0 – Protrusion])
	MaleFitting();
	}
	}

	//——————-
	// Mystery brush

	module ScrubbyTool() {

	union() {
	translate([0,0,60.0])
	rotate([180,0,0])
	difference() {
	union() {
	cylinder(d1=EndStop[OD1],d2=31.8,h=10.0);
	translate([0,0,10.0 – Protrusion])
	cylinder(d1=31.8,d2=31.0,h=50.0 + Protrusion);
	}
	translate([0,0,-Protrusion])
	cylinder(d1=26.0,d2=24.0,h=100);
	}
	translate([0,0,60.0 – Protrusion])
	MaleFitting();
	}
	}

	//——————-
	// eBay horsehair dusting brush

	module DustBrush() {

	union() {
	translate([0,0,40.0])
	rotate([180,0,0])
	difference() {
	union() {
	cylinder(d1=EndStop[OD1],d2=31.8,h=10.0);
	translate([0,0,10.0 – Protrusion])
	cylinder(d1=31.6,d2=31.8,h=30.0 + Protrusion);
	}
	translate([0,0,-Protrusion])
	cylinder(d1=26.0,d2=24.0,h=100);
	}
	translate([0,0,40.0 – Protrusion])
	MaleFitting();
	}
	}


	//——————-
	// Electrolux brush ball

	module LuxBrush() {

	union() {
	translate([0,0,30.0])
	rotate([180,0,0])
	difference() {
	union() {
	cylinder(d1=EndStop[OD1],d2=30.8,h=10.0);
	translate([0,0,10.0 – Protrusion])
	cylinder(d1=30.8,d2=30.0,h=20.0 + Protrusion);
	}
	translate([0,0,-Protrusion])
	cylinder(d1=25.0,d2=23.0,h=30 + 2*Protrusion);
	}
	translate([0,0,30.0 – Protrusion])
	MaleFitting();
	}
	}



	//———————-
	// Build it!

	if (Layout == "MaleFitting")
	MaleFitting();

	if (Layout == "CoilWand")
	CoilWand();

	if (Layout == "FloorBrush")
	FloorBrush();

	if (Layout == "CreviceTool")
	CreviceTool();

	if (Layout == "DustBrush")
	DustBrush();

	if (Layout == "ScrubbyTool")
	ScrubbyTool();

	if (Layout == "LuxBrush")
	LuxBrush();

view raw Kenmore Wand Bushings.scad hosted with ❤ by GitHub

2016-08-24

Michelin Protek Max Tubes

Within the space of four days, we had three rear-tire flats:

A tire liner wear-through, after which I didn’t replace the liner
Four miles later, a blowout through a tread gash previously covered by the tire liner
A puncture flat directly through the tread

Basically, erosion from the (last remaining, I think) liner in the rear tire of Mary’s bike caused the first flat; I patched the tube and didn’t notice the gash. After the blowout, I patched the tube again, booted the gash (with a snippet from a roll of PET bottle plastic I carry around for exactly that purpose), stuck an ordinary patch atop the boot to cover its edges, and the whole mess has held air just fine for the last week. I’m reluctant to mess with success.

Not having a tire liner caused the third flat, this time on my bike. The wound looked like a nail or glass shard punched directly through the Kevlar armor behind the tread. Fortunately, it happened (or, more exactly, I realized I had a flat) half a mile from home, so I fired a CO₂ cartridge into the tube and pedaled like crazy, which got me halfway to the goal and I rolled the rest of the way on a dead-flat tire.

Ya can’t win.

So I picked up a pair of Michelin Protek Max tubes, the weirdest things I’ve ever stuffed into a bike tire:

Michelin Protek Max Tube - carton — Michelin Protek Max Tube – carton

The bumps along the tread surface are much larger and uglier than shown in that picture:

The rubber forming the protrusions has the same thickness as the rest of the tube, so you’re looking at soft, flexible shapes, rather than thick bumps.

The “liquid” inside must be a thin film over the inner surface. I’ve never been a big fan of tire sealants, mostly because they’re reputed to ooze to the bottom of the tire into off-balance puddles.

For future reference, the Official Quasi-Instruction Manual / Blurb (clicky for more dots):

Michelin Protek Max Tube - instructions — Michelin Protek Max Tube – instructions

We’ll see how well these work…

2016-08-14