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.

Tag: Repairs

If it used to work, it can work again

  • Can Opener Drive Gear: FAIL

    The fancy OXO can opener doesn’t work well on #10 cans, so we bought a not-bottom-dollar can opener with comfy handles to replace the one that convinced us to get the OXO. After maybe a year, tops, it gradually stopped working well, too, which prompted a trip to the Basement Shop Workbench.

    The symptoms:

    • The handle wouldn’t move the cutter during maybe 1/4 of its revolution
    • It pushed the handles apart during another quarter turn

    Look carefully and you’ll see the teeth sticking out slightly more on the right side of the drive wheel:

    Can opener - drive gear misalignment
    Can opener – drive gear misalignment

    When those protruding teeth line up with the gear behind the cutter wheel, the handles open and the drive wheel loses its grip. When the low side lines up with the cutter gear, the gears very nearly disengage.

    Taking it apart shows that both “gears” (which is using the term loosely) have been pretty well chewed up:

    Can opener - gears and cutters
    Can opener – gears and cutters

    Destroying those gears should require a lot more strength than either of us can deploy on a regular basis, which suggests they used mighty soft steel. It’s not obvious, but the drive gear hole is just slightly larger than the screw thread OD; it doesn’t ride on an unthreaded part of the screw shaft.

    I’m not in the mood for gear cutting right now, so I filed down the wrecked teeth and buttoned them up with some attention to centering the gear. The can opener works, but sheesh this is getting tedious…

  • Using a 3-way X10 Wall Switch As a 2-way Switch

    The pushbutton on the X10 wall switch controlling the fiercely incandescent lamp over the kitchen table has gotten erratic, so I dug into the Big Box o’ X10 Crap for a replacement. Turns out The Box has only 3-way switches, but the lamp needs a standard two-wire switch.

    The instruction sheet shows this diagram:

    X10 3-way Wall Switch Wiring
    X10 3-way Wall Switch Wiring

    The pushbutton on the CS277 “Companion” switch connects the red lead to the two blue leads. The blue leads are always connected together and carry the lamp current, so the red lead is just a signal from the remote button.

    The WS477 “Master” switch will work as an ordinary switch if you cap the red lead with a wire nut and tuck it into the box.

    Done!

  • 2000 Toyota Sienna: Replacing the Bank 1 Sensor 2 Oxygen Sensor

    Shortly after replacing the battery, the dreaded Malfunction Indicator Lamp popped on with a P0420 error code that, according to the Nice Man at Autozone, translates into “low catalytic converter efficiency”. A bit of diagnostic sleuthing reported that the most likely cause was an exhaust leak, followed by an out-of-calibration downstream oxygen sensor, followed by a bad converter. Internet lore has it that replacing the cat cracker is a dealer-only event (here in New York State, with a van sporting the California emissions package) that costs upwards of $2 k, which seems excessive for a 14-year-old van.

    Actually, the most probable cause was replacing the battery: the brief power outage wipes out the stored performance data for the emissions control machinery. Because we make only short trips and it’s been bitterly cold, the algorithms may conclude the converter’s dead when it’s just a matter of measuring the variables under suboptimal conditions.

    With all that in mind, after a peek under the van ruled out the exhaust leak, I decided to replace the oxygen sensor. All this happened during a week when the outdoor temperature hovered around 10 °F = -12 °C, but the forecast called for an atypical January day with a high of 55 °F = 13 °C; I might not get a second chance before the annual inspection came due in February.

    The sensor is relatively cheap (about $70 at the local Autozone) and, entirely unlike Bank 1 Sensor 1, readily accessible on the tailpipe downstream of the cat cracker:

    Sienna Bank 1 Sensor 2 - in place
    Sienna Bank 1 Sensor 2 – in place

    The OEM sensor cable runs in a sheath held to the chassis with a plastic clamp:

    Sienna Bank 1 Sensor 2 - cable clamp
    Sienna Bank 1 Sensor 2 – cable clamp

    Jamming a small screwdriver into the clamp released the tongue and the sheath. The sheath vanishes into the van’s interior through a squishy rubber boot, with a crimped metal band joining the two:

    Sienna Bank 1 Sensor 2 - floor boot
    Sienna Bank 1 Sensor 2 – floor boot

    Internet lore would have you believe you can replace the sensor without removing the front passenger seat, but it’s much easier if you remove the four bolts, disconnect the seat sensor, and lay the seat on its back:

    Sienna Bank 1 Sensor 2 - interior connector
    Sienna Bank 1 Sensor 2 – interior connector

    More fiddly-diddly with the screwdriver under the van wrecked the band enough to separate sheath from boot, at which point deploying the BFW with the magic oxygen sensor socket showed that the anti-seize compound on the sensor’s thread worked as intended: after one oomph the sensor turned out by hand.

    Then you just punch the boot through the floor and bring it all inside to splice new sensor onto OEM connector. Standardization is a wonderful thing; the sensor cable may use any one of eight color codes. The Toyota OEM sensor was a “Type B” that matches up with the Bosch replacement sensor thusly:

    • Heater = two black leads ↔ two white leads
    • Signal = blue lead ↔ black lead
    • Ground = white lead ↔ gray lead

    Although the splice block has water-resistant seals, I figured putting it inside the van couldn’t possibly be a Bad Idea, so there it is, nestled snugly into the recess in the floor:

    Sienna Bank 1 Sensor 2 - splice block
    Sienna Bank 1 Sensor 2 – splice block

    Picked up a nice new Autel AL519 OBD Code Scanner from the usual Amazon vendor, reset the trouble code, drove to-and-from Squidwrench (across the river, just barely far enough to reset the performance data), and so far it’s All Good. The motivation for getting my very own scanner, rather than returning to Autozone, is that the AL519 can do real-time graphing and data capture from various sensors, so I can perform Science! should the spirit move me.

    The AL519 has a USB connection that appears as a USB serial device but, alas, the relentlessly Windows-centric host program won’t run under Wine.

  • Whirlpool Refrigerator Drawer Strut Repair

    The strut supporting the two drawers in the bottom of the refrigerator came out in two pieces during a recent cleaning session. To judge from the condition of the joint, I’d done this once before in its history:

    Refrigerator strut - tab clamps
    Refrigerator strut – tab clamps

    That tab inserts into a slot in the front of the elaborate frame that supports the drawers, where it’s captured by a metal bar. Should you lift the rear of the strut without first removing the bar, the tab snaps off at the base. I’ve annotated the top of the strut in the hopes of reminding me the next time around.

    A pair of bumps at the front of the drawer guides should hold the drawers closed, but it’s pretty obvious that’s not working as intended:

    Refrigerator strut - worn retainers
    Refrigerator strut – worn retainers

    I shaped strips of phosphor bronze spring stock around the bumps:

    Refrigerator strut - phosphor bronze covers - top
    Refrigerator strut – phosphor bronze covers – top

    The bottom view shows they’re held in place by crimps and a generous dollop of faith:

    Refrigerator strut - phosphor bronze covers - bottom
    Refrigerator strut – phosphor bronze covers – bottom

    That should serve until I know whether the plastic drawer rail will carve through the metal. The drawers slide out with much more enthusiasm now, so it’s a Good Thing until something else breaks.

    Yes, this is the refrigerator with the Freezer Dog

  • Plastic Stress in Polarized Light

    Here’s what the (cracked) faceplate of the FC1002 Frequency Meter looks like, through polarizing filters that reveal the internal stress.

    A circular polarizer screwed on the lens:

    FC1002 Frequency Counter - faceplate - circular polarizer
    FC1002 Frequency Counter – faceplate – circular polarizer

    A sheet of linear polarizing film held in front of the lens:

    FC1002 Frequency Counter - faceplate - linear polarizer
    FC1002 Frequency Counter – faceplate – linear polarizer

    For reference, none of the other instrument faceplates on the bench show anything other than uniform gray, with one exception that points directly to the plastic injection point.

    I’d say this plate cracked due to unrelieved internal stresses and not anything I did or didn’t do.

  • FC1002 Frequency Counter Battery Pack

    The main reason for taking the FC1002 frequency counter apart was to replace the failed quad-AA NiCd battery pack. Rather than buy new cells with tabs, I recycled some low-discharge “ready to use” NiMH cells from the heap. Back in 2009, they looked like this:

    Tenergy RTU Pack A Tests - Aug 2009
    Tenergy RTU Pack A Tests – Aug 2009

    Nowadays, they’re a bit less peppy:

    Tenergy RTU - 2014-01 - loose cells
    Tenergy RTU – 2014-01 – loose cells

    The red blooper shows that you can’t trust a smart fast charger to get the right answer; it concluded that pair was fully charged. After the discharge test and an overnight C/10 charge, they regained as much enthusiasm as they’ll ever have.

    They have slightly less capacity than in 2009 and also a somewhat lower terminal voltage. That shouldn’t matter here, as the frequency meter has a power supply to take care of that problem.

    Although I’ve sometimes been able to (quickly!) solder directly to ordinary AA cells, a trial run on a defunct RTU cell showed that wasn’t going to work on whatever variety of steel they used, no matter how much I scuffed it and despite using aggressive flux that normally blends silver solder onto stainless steel.

    Fortunately, the top half of a four cell case fit exactly in the space available, so I used woven copper fabric tape inside the case to interconnect the cells, then lashed everything together with the obligatory Kapton tape:

    FC1002 Frequency Counter - battery pack
    FC1002 Frequency Counter – battery pack

    That cracked faceplate isn’t the nicest thing to confront, but it’ll suffice until I get more motivation:

    FC1002 Frequency Counter - repaired
    FC1002 Frequency Counter – repaired

    I’ve misplaced my stack of Round Tuits again…

  • Toyota Sienna: Key Wear

    And it came to pass in the Christmas Season that our ignition keys began jamming in the lock, rather than just starting the van. It seems Toyota used split wafers in their locks up through the early part of this millennium, with the result that the delicate wafer edges tend to wear out both themselves and the edges of the keys.

    I can’t vouch for the wafers, but the keys definitely aren’t in good shape:

    Ignition keys - worn vs new
    Ignition keys – worn vs new

    Given that picture, someone can probably conjure up a shiny new key and drive away with our 14-year-old Sienna van. It just rolled over 90 k miles and is in pretty good condition. New battery and hood prop pivot, too.

    Being that type of guy, the first thing I did with the new van was to get duplicate keys and drop the OEM keys into the “2000 Sienna” file folder. The middle key in that photo has had maybe a dozen uses and is in pristine condition.

    Rumor has it that one can cannibalize a set of split wafers from the glove box lock:

    Glove box latch
    Glove box latch

    Or, according to different sources, you can simply discard the split wafers and be done with it.

    The trick to removing the lock cylinder lies in turning the key to the Accessory position, then poking a pointy object into a small hole to depress an internal spring-loaded pin. Of course, one must disable the air bags, dismantle the steering wheel, and remove half a dozen trim panels to reveal the small hole.

    Fortunately, the two “new” keys from the file folder work perfectly and we’ll run with them for a while. I suppose I should get another set of duplicates, but …