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: Machine Shop

Mechanical widgetry

  • Frostproof Faucet: Attempted Repair Part 1

    Our house has three frostproof hose faucets, with the closest one to the garden being inside the garage. Unlike ordinary garden faucets (a.k.a., hose bibs), these have the valve seat at the end of a foot-long tube that projects inside the foundation wall where it (usually) can’t freeze. The valve has required increasing amounts of force to turn off (meaning the ancient washer inside has solidified) and the packing around the stem has begun leaking copiously with the faucet turned on (despite tightening the cap).

    I’ve been putting this repair off ever since we bought the house, because I knew how it would end, but with no rain for nearly a month before planting season the garden needed water. So, we begin…

    The first complication is that, while there’s a shutoff valve for the faucet, I’m reluctant to turn its corroded-in-place stem for fear of starting up an indoor leak:

    Corroded gate valve
    Corroded gate valve

    The small stem to the left of the valve body is a drain cap, which means that one can, in theory, turn off the valve and remove the cap to drain water from the line to the left. That line leads downhill to the faucet, which will turn out to be critically important later in this story. FWIW, I think it’s a gate valve, given the length of the casting around the stem, but for obvious reasons I haven’t opened it up to find out. If it’s a washer-based valve, it hasn’t been closed in decades and I expect the washer & seat to be in poor condition.

    The house has an unusual plumbing arrangement: a direct line from the water inlet to the outdoor faucets, toilet flush valves, and a separate faucet at the kitchen sink. This originally fed well water directly to those points, meaning that the largest water consumers didn’t go through the water softener and they weren’t watering the lawn with soft water. I took pains to preserve that arrangement while replacing the softener and having the town water supply plumbed into the house.

    In any event, I shut off the water upstream of the shutoff valve (hence, no toilet flushing for the duration) and proceeded.

    The valve handle came off easily, as did the cap, revealing the crumbling stem packing inside:

    Frostproof faucet - stem packing material
    Frostproof faucet – stem packing material

    Nota bene: the builder firmly cemented the faucet into the foundation wall. The same cement was applied on the inside wall, so removing the faucet requires chiseling out what might be the entire depth of the faucet through the foundation blocks. That’s one of the many reasons I didn’t want to do this project: the possible failure modes looked grim.

    With that out of the way, the stem support came loose easily; old-school heavy brass construction works great:

    Frostproof faucet - stem support
    Frostproof faucet – stem support

    Unfortunately, unscrewing the stem eventually reached the point where it spun freely, but refused to pull out. That means the washer a foot inside the valve has swollen beyond the minor diameter of the threads near the seal and that means I must destroy the washer to extract it. The usual advice recommends pulling on the stem with pliers, but … suffice it to say that was not sufficient in this situation, not to mention that I didn’t want to goober up the stem.

    Here’s the nose of my homebrew slide hammer, with a 10-24 steel screw in the valve stem and a pair of nuts jamming everything in place:

    Frostproof faucet - valve handle with slide hammer nose
    Frostproof faucet – valve handle with slide hammer nose

    I hoped that the valve handle would prevent the screw from distorting the stem if this operation required force majeure and that part worked out perfectly: a few whacks pulled the stem out and left the washer behind. Some tedious fishing, using various all-thread rods to grab the washer and then fragments of the washer and then fragments of the fragments, eventually produced this tableau:

    Frostproof faucet - stem with slide hammer
    Frostproof faucet – stem with slide hammer

    A closeup of the seal end, with the larger fragments of the old washer and a replacement beveled washer of about the right size:

    Frostproof faucet - valve with washer
    Frostproof faucet – valve with washer

    The brass screw turned out easily, the new washer went on, I reassembled everything in reverse order, put new valve packing material under the cap, and… of course, the valve leaked when I turned it off.

    A frostproof valve tends to dribble after being shut off, because there’s a foot of nearly horizontal pipe that must drain completely, but this leak was in the gallon-per-hour territory. Obviously, the situation had gone from bad to worse, exactly as I’d expected.

  • Sears Kenmore Dryer Rattle: Quieter

    Our re-sealed Kenmore clothes dryer developed a horrible rattle that Went Away with slight pressure here & there on various surfaces. I eventually located the most sensitive spot: inside the lint filter duct, on its upper surface. That suggested something lying atop the duct.

    Remove the two screws securing the duct to the top surface, push forward on the back of the control panel, and the front of the top panel pops up. Tilt upward against the springy hinges, peer in above the duct, and what do we find?

    Kenmore dryer - wire routing
    Kenmore dryer – wire routing

    Yup, wires resting on the duct!

    There are no obvious wire guides to be found, so I’m pretty sure those wires were in pretty much that same position when I dismantled the dryer to install the new seal. In any event, they are where they are.

    This not being a particularly hot area, I slipped a sheet of closed-cell foam between the wires and the duct, snapped the top down, and screwed the duct in place.

    The lower catches on the front panel seem to be loose, too, so a pair of cardboard shims jammed discreetly into the lower edge of the joint on either side soaked up some spare motion with excellent noisemaking potential.

    Unfortunately, fixing that rattle exposed another buzz that seems to be a loose plate buried somewhere in the back of the cabinet. Getting in there requires tearing the whole thing apart, which I’m not looking forward to in the least.

  • Whirlpool Refrigerator Fan Noise: Final Fix Redux

    Well, using a PC case fan as a freezer blower seemed like a good idea at the time: it worked, moved an adequate amount of air, and was pretty nearly silent. Until, that is, frost built up on the blades, water froze inside the frame, and the thing began sounding like a stick running along a picket fence:

    Frosted PC case fan in freezer
    Frosted PC case fan in freezer

    I replaced the first fan with another having slightly more clearance between the blade tips and the frame, but to no avail.

    So I dug the OEM fan (a.k.a., the Freezer Dog) from the heap, dismantled it, and discovered why it was howling. Turns out that the shaft nearest the fan blades was scored inside that bearing:

    Freezer motor - scored shaft
    Freezer motor – scored shaft

    A closer look:

    Freezer motor - scored shaft detail
    Freezer motor – scored shaft detail

    The rest of the shaft looked fine to me, so I put some green Loctite on rotor at the shaft and shoved the long end of the shaft (using the drill press as an arbor press) to put the scored section inside the rotor:

    Freezer motor - relocated rotor
    Freezer motor – relocated rotor

    Yes, that’s the same Loctite ridge you saw there

    The shaft has several small grooves that probably held lubricant or acted as alignment guides or something useful, but I’m hoping none of that matters. The rotor is turning backwards now, too, which shouldn’t make much difference: it’s pretty much symmetrical.

    While I had the motor apart, I whacked the bearings with a rod to shrink them a bit:

    Freezer fan bearings
    Freezer fan bearings

    Slobbered more STP on the bronze bearings, reassembled everything again, and it’s been quiet for nearly a week.

    Perhaps the combination of new shaft surfaces and tweaked bearings will run for a few more years. I still have the “new” replacement fan in a box…

  • Soaker Hose Splicing

    We deployed several granulated-rubber soaker hoses last year and, while they certainly weep enough water, they’re exceedingly brittle: they kink and break with what seems to be ordinary handling.

    The hose ID is much smaller than ordinary “half inch” hose, so I turned some grooves on a chunk of copper tube that’s a snug fit inside:

    Grooving copper tubing
    Grooving copper tubing

    Slitting a piece of scrap hose (ya gotta have stuff) and clamping it around the hose and tubing holds the splice together against the 90 psi water in the Vassar Farms irrigation system and provides a bit of strain relief beyond the ends of the tubing:

    Spliced soaker hose
    Spliced soaker hose

    While I was at it I made three more copper splices, because I know they’ll come in handy…

  • Ouch!

    Got one of those painful, bloodless slices:

    Split thumbprint
    Split thumbprint

    From, believe it or not, the razor-sharp edge of a fillet of cured green Loctite:

    Freezer motor shaft - Loctite fillet
    Freezer motor shaft – Loctite fillet

    Of course, it didn’t stay bloodless for long: every time I put pressure on the ball of my thumb, the split gets longer.

    I hate it when there’s blood all over the workpiece…

  • Brita Pitcher Lid: Second Hinge Pin Failure

    Although that fix continues to work, the second pin failed pretty much as expected:

    Brita pitcher lid - second broken pin
    Brita pitcher lid – second broken pin

    I glued the pin to rebuild the base, sheared the pin off, extracted the matching screw from the Tiny Vial of Teensy Screws, drilled a hole, and forced it in. This shot of the underside of the pitcher lid clearly shows that drilling the hole perpendicular to the edge doesn’t produce the proper alignment, but it works well enough:

    Brita pitcher lid - pin angle
    Brita pitcher lid – pin angle

    The “Smart Pitcher” LCD panel in the lid that counts down six weeks until filter replacement didn’t survive its most recent trip through the dishwasher, so we’re reduced to marking the calendar. How 20th century…

  • Quilting Pin Caps

    Mary has been quilting up a storm lately and is growing dissatisfied with the special safety pins she’s been using to hold the layers together. Long straight pins are ideal, except that maneuvering a large quilt through her sewing machine resembles stuffing a porcupine into a keyhole. A commercial solution costs nearly half a buck per pin, which seems unreasonably spendy for something you need by the hundreds.

    We kicked around some finger- and quilt-friendly dimensions and I cobbled up a solid model:

    Quilting Pin Cap
    Quilting Pin Cap

    Which turned into an array of small octagons that won’t roll off the table:

    Pin cap array on build platform
    Pin cap array on build platform

    We figured 25 would be enough to decide if this is workable and whether the dimensions fit fingers, pins, and quilts.

    Filling them with silicone rubber required one squirt each:

    Filling pin caps with silicone
    Filling pin caps with silicone

    The trick with the silicone rubber is to cut the snout so it fits flat on the cylinder top. Put the cylinders on a piece of non-stick paper (I used the back of the carrier for some double-sided tape, but wax paper would be better), hold one with tweezers, squirt in enough rubber to fill the cylinder solidly from bottom to top, then slide the snout sideways to smooth the surface.

    Wait for a day, pop them off, and remove any drool:

    Silicone-filled pin caps
    Silicone-filled pin caps

    It’s garden planting time right now, so it’ll take a while before I tweak the design and run off the next batch.

    I don’t know how to compute an actual cost for each of those things. I regard the entire Thing-O-Matic as fully depreciated and pretty much a sunk cost, which means the expense boils down to the incremental cost of plastic and silicone. All the Quality Shop Time is, of course, free… and maybe even therapeutic.

    The (trivially simple) OpenSCAD source code:

    // Quilting pin caps
    // Ed Nisley KE4ZNU April 2012
    
    //- Extrusion parameters must match reality!
    //  Print with +1 shells and 3 solid layers
    
    ThreadThick = 0.25;
    ThreadWidth = 2.0 * ThreadThick;
    
    HoleWindage = 0.2;
    
    function IntegerMultiple(Size,Unit) = Unit * ceil(Size / Unit);
    
    Protrusion = 0.1;			// make holes end cleanly
    
    //----------------------
    // Dimensions
    
    ID = 5.0;
    OD = ID + 2*ThreadWidth;
    Length = 5.0;
    Sides = 8;
    
    //----------------------
    // 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);
    }
    
    module ShowPegGrid(Space = 10.0,Size = 1.0) {
    
      Range = floor(50 / Space);
    
    	for (x=[-Range:Range])
    	  for (y=[-Range:Range])
    		translate([x*Space,y*Space,Size/2])
    		  %cube(Size,center=true);
    
    }
    
    //----------------------
    // Build them!
    
    ShowPegGrid();
    
      rotate(180/Sides) {
    	difference() {
    	  PolyCyl(OD,Length,8);
    	  translate([0,0,-Protrusion])
    		PolyCyl(ID,(Length + 2*Protrusion),8);
    	}
      }