Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.
For quite some time, the Canon S630 printer connected to the file server downstairs has been printing some documents in what looks like garbled reverse video: all of the text areas render as white characters on a black background, with peculiar graphic gibberish filling the space to the right margin. I’d provide a picture, but it wouldn’t be too informative; suffice it to say that if I wasn’t using bulk ink the pages would cost about a buck each.
Printing documents with two-up pages (two document pages on one paper sheet) generally resulted in the first sheet coming out garbled with the remainder emerging unscathed, but sometimes I found an entire stack of black paper. Ouch!
This usually affected documents printed from Web pages, but sometimes clobbered pure PDF documents. Given that Linux printing involves multiple transformations between Postscript / Ghostscript / PDF / PNG / what-have-you, it’s impossible to pin down a common cause.
Searching for the obvious keywords showed other folks had similar problems with different printers and different drivers. None of the threads had any resolution.
Printing the same document on the Epson R380 worked perfectly.
One recent morning I had four out of six documents fail, so I tried some of this and a little of that, before it occurred to me that I should switch the driver. I had chosen the default recommended printer driver during installation: the oddly named bj8xxyyz.upp file produced by the Ghostscript folks. Switching to the Gutenprint 5.2.7 driver seems to have solved the problem; all four failing documents printed perfectly and the problem hasn’t returned in a week of printing.
The R380 was already using the Gutenprint driver, which (in retrospect) should have been a big, fat hint.
I’d file a bug report, but to which project about what? [sigh]
The plunger is basically a pin that eventually deforms the top of the switch membrane. Tee’s DSC-H1 had an exposed switch, although this picture shows that membrane was still in reasonably good condition:
Shutter Switch Closeup
My DSC-H5 has a thin black protective disk atop the switch, but the disk wasn’t particularly protective and developed a dimple that held the contacts closed even with the shutter button released (which is why I’m tearing the camera apart in the first place):
DSC-H5 Shutter Switch – dimpled protector
The C-clip around the plunger is now plastic, rather than metal, making it less likely to erode the thin plastic shaft. Pulling the clip off while holding the button down releases all the parts:
DSC-H5 Shutter Button – components
A few measurements from an intact shutter button, which may come in handy if you don’t have one:
DSC-H5 Shutter Button – plunger measurements
Mount three-jaw chuck on the Sherline table, laser-align chuck to spindle, grab shutter button by its shaft in a Jacobs chuck, grab shutter button in three-jaw chuck, release from Jacobs chuck:
DSC-H5 Shutter Button – in Sherline chuck
That’s not particularly precise, but it’s close enough for this purpose. I used manual jogging while testing the fit with a paper shim until all three jaws had the same clearance, then tightened the jaws.
I nicked the plunger at its base with a flush-cutting diagonal cutter, snapped off the plunger, and drilled a #56 hole through the button:
DSC-H5 Shutter Button – cap drilling
For reasons that made sense at the time, I repaired Tee’s DSC-H1 with a 1-72 brass screw. This time, I used an 0-80 (which I learned as ought-eighty, if you’re wondering about the indefinite article) screw and nut, because the screw head fit neatly into the bezel recess and I had a better idea of how to smooth out the threads.
This being plastic, I used the chuck to hold the tap in the proper alignment, then turned the tap through by finger pressure. This trial fit showed it worked:
DSC-H5 Shutter Button – 0-80 screw
Milling the nut down to a 2.8 mm cylinder required the usual manual CNC, with repeated iterations of this chunk of code in the MDI panel:
The 2.8 in the first line is the current OD and the 3.11 is the measured diameter of the 1/8 inch end mill. I started from a 5.0 mm OD that just kissed the nut, then worked inward by 0.2 mm at a time for very shallow 0.1 mm cuts:
DSC-H5 Shutter Button – 0-80 nut milling
The alert reader will notice, as did I, that the head isn’t quite centered: the cut trimmed the left side and left the right untouched, with an offset far larger than the centering error. As nearly as I can tell, the heads of those screws aren’t exactly centered on their threaded shafts, but the final result fixed that… and the overall error is a few tenths of a millimeter = maybe 10 mils, tops, so it’s no big deal.
With all that in hand, I applied a very very thin layer of epoxy to fill the threads below the now-cylindrical nut and convert the screw into a rod:
DSC-H5 Shutter Button – 0-80 plunger
My original intent was to use the screw head as-is atop the PET shield (per those instructions) on the switch membrane, but after reassembling enough of the camera to try that out, it didn’t work correctly: the half-pressed switch didn’t activate reliably before the full-pressed switch tripped.
The PET shield I used came from the side of a 1 liter soda bottle and turned out to be 0.27 mm thick:
DSC-H5 Shutter Switch – cover removed
I think the PET shield would work with the original plunger shape concentrating the force in the middle of the shield, but the nice flat screw head spreads the force out over a wider area. As a result, the force required to close the half-pressed switch contacts was roughly the same as that required to close the full-pressed contacts; remember the nub on the bottom of the black plastic tray concentrates the force in the middle of the full-pressed switch membrane.
So I removed the PET shield, added a dot of epoxy to fill the screw slot and compensate for the missing shield thickness, then filed a flat to make a nice pad:
DSC-H5 Shutter Button – epoxy on plunger
Reassembling the camera once more showed it worked exactly the way it should. In fact, the button seems more stable than the OEM version, probably because the slightly enlarged plunger shaft fits better in the bezel. Too bad about those scuffs on that nice shiny button dome, though:
DSC-H5 – repaired shutter button
Tossing the leftover parts seems entirely appropriate…
The half-pressed shutter switch position on my Sony DSC-H5 recently stopped working, which seems to be one of two common failures. The other, a broken switch shaft, happened to Tee’s camera, as described there, and I figured I should preemptively fix that while I was inside my camera.
This being a common failure, several folks have described how to dismantle the camera; I followed that guide’s English version.
The DSC-H5 differs slightly from that description. After I got the thing apart, it became obvious that there’s no need to remove the LCD panel, the main control board, and most of the ribbon cables if you have a Philips #0 or #00 screwdriver with a very thin shaft. There’s no way to describe this operation, so take it apart his way, then you’ll see what I mean: the guts can come out as one big lump.
In any event, all the camera controls eventually emerge from the body:
DSC-H5 Control Assembly
Looking back into the camera body reveals the bottom of the shutter button, captured by a static discharge contact and the gray plastic frame of the Focus / Break button caps:
DSC-H5 Shutter Button – interior view
Removing the pushbutton frame and pushing the left button bezel latch with a small flat-blade screwdriver extracts the shutter button; it falls out of the inverted body. This is one of the few intact DSC-H[1-9] shutter buttons you’ll ever see:
DSC-H5 Shutter Button – bottom view
Those rectangular protrusions lock into the slots in the black plastic cap that appears almost silver in this front view that shows the dimple in the switch membrane:
DSC-H5 Shutter Button Switch – depressed surface
You must remove the cap to release the flex PCB with the shutter switches. Two heat-staked pins retain the cap; a scalpel neatly slices off the melted plastic:
DSC-H5 Shutter Switch – cover removed
Nota bene: the DSC-H1 button bezel I repaired earlier does not have features that lock into the cap over the switch assembly, which means you can remove and replace it without disassembling the camera. You cannot remove or install the DSC-H5 button without taking the camera apart. I suppose this counts as a continuous product improvement, but …
The shutter switch has two parts:
The full-press switch that takes the picture (the white dot on the blue flex, shown above)
The half-press switch that triggers the focus & exposure is in a black plastic tray (seen edge-on above the white dot)
The bottom of the half-press tray has a small nub that activates the full-press switch, so the force required to activate the half-press switch must be considerably less than the force that activates the full-press switch. This turns out to be a critical part of the repair…
A closeup of the half-press switch with the protective cover sheet (the “damn confetti” of the disassembly instruction) and the dimple that held the contacts together with the button released:
DSC-H5 Shutter Switch – dimpled protector
A closeup of the switch through a snippet of PET plastic shows the switch membrane itself is in fine shape:
DSC-H5 Shutter Switch – cover removed
However, the new plastic shield did not work out well, for reasons having to do with the new button plunger. That’s the next step: rebuild the plunger…
One of the ribs in the six-passenger umbrella we keep in the van snagged on something and snapped its fitting on the spreader strut:
Umbrella strut – broken connector
This being wonderful engineering plastic that cannot be solvent-bonded, epoxy is the only adhesive that will work. However, those joints undergo tremendous stress in a deployed umbrella, so a bare epoxy joint won’t have enough strength for the job. What to do?
Wonder of wonders, when I got the umbrella into the Basement Laboratory Repair Wing, I discovered:
The not-quite-round strut fitting stub slipped right into a short brass tube from the heap and
Just enough of the fitting remained on the rib to anchor the tubing
A silicone tape wrap kept most of the epoxy inside while it cured:
Umbrella strut – epoxy curing
Clearing off a few blobs made it all good:
Umbrella strut – brass tubing splint
We don’t play golf, but such a big umbrella keeps most of the rain off two people; it’s a tchotchke from back when Mary worked at IBM (hence the color scheme). We call it our “six-passenger” umbrella because it looks about that big when we deploy it…
The bikes stand upright inside the van and the helmets ride on the floor with all their stalks sticking up. This usually works out well, but on our last trip my helmet rolled under my bike and rubbed the foam ball surrounding its mic against the chain, producing a result so awful that I had to install new foam.
The foam comes from a sheet of Sonex acoustic foam baffle, snipped into a reasonable approximation of a ball, with a slit deep enough to surround the mic, and a cable tie holding it closed:
Foam mic ball on bike helmet boom
For what it’s worth, I’ve found that excessive wind noise correlates with too much mic gain. The mic rides about a finger’s width from the corner of my mouth, I talk at a normal volume, the amp supplies about 20 dB of gain, and we have no trouble with wind noise. The amp gain depends on the mic sensitivity, so your results will certainly differ; these mics came from the heap with no specs whatsoever.
I suppose wind noise also depends on the bike’s speed, but when I’m going that fast I don’t have enough brain or lungs left over to hold a conversation…
The absurdly heavy pump nozzle atop the kitchen sink soap dispenser seemed more wobbly than usual. Some investigation suggested the fitting atop the plastic pump has gotten smaller, which may be due to having the nozzle wobble around on it.
In any event, a wrap of Kapton tape snugged it up just fine:
Sink soap dispenser pump
We’ll see how long that lasts; this thing may be nearing the end of its useful life.
Our Toyota Sienna arrived with a blank cover plate where a fancier model would have a switch. It seemed a shame to let that space go to waste, so I popped the plate out, rummaged around in the heap, found a small circuit board with a blinky LED that just exactly fit the space available, and drilled a suitable hole:
Sienna anti-theft blinker – inside
When it’s installed in the van, it looks and acts just like the security system we don’t have. For all I know, that plate was for the security system control, so perhaps it’s an exact match!
Sienna anti-theft blinker – bezel
The batteries last about two years, a few months later I notice the lack of blinkiness (it’s hidden behind the steering wheel in my normal driving position), and eventually I replace the corroded batteries. This time, I had to replace the entire battery holder; things got pretty nasty in there.
As I recall, the PCB came from a fancy “greeting card” mailed to me by the Business Software Alliance, with the implied threat that if all my paperwork wasn’t up to par, my use of potentially unlicensed software would blow up in my face. That was back in the day when mailing something that pretended to be a bomb was considered a cute joke and when I actually ran more than one Windows PC.
The Smell of Molten Projects in the Morning 