Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.
After having discovered, once again, that the vacuum cleaner wasn’t cleaning very well because the suction control was knocked halfway down the scale, I made the normal setting on the damn thing visible:
Samsung vacuum cleaner control labeling
I don’t know why a label in dark-gray-on-black is such a wonderful idea, given that SAMSUNG stands out in pure white-on-red. Designers love subtle touches; I suppose they expect you to just puzzle it out and memorize the right answer.
The embossed / raised black-on-black symbols don’t work for me, either. Did you spot the one to the left of the ON/OFF label? Didn’t think so.
So I bought a lurid green $8 Tomodachi Santoku knife at K-Mart, which was the first non-stick-coated Santoku-shaped knife I’d seen since that comment. It’s made by Hamilton Forge Ltd, one of those generic names that doesn’t produce any search results worth mentioning and so probably isn’t a real company:
Tomodachi Santoku knife
The knife has a huge steel blade with a solid plastic handle injection-molded around a short tang, which put the balance point maybe 50 mm out into the blade. I didn’t like the feel when I waved it around in the store and really didn’t like how it behaved on the cutting board.
The way I see it, I can fix a too-light handle…
Pursuant to that post, I have a bag of tungsten electrodes, some complete with a glass seal:
Tungsten electrode with glass seal
Wrapping some masking tape around the glass, tapping it with a hammer, then sliding the tape-with-fragments into the trash got rid of the glass. The bulbous tip seems to be a stainless steel tube welded around a thin tungsten shaft, so I clamped it in the vise and whacked it with a chisel; tungsten is strong-but-brittle and cracks easily:
Fracturing tungsten electrode
Of course, whacking a tungsten rod didn’t do the chisel the least bit of good, but it was about time to sharpen that thing anyway.
Why use tungsten electrodes instead of, say, ordinary drill rod? Tungsten has about the highest density you can get without going broke, getting poisoned, or dying of radiation exposure. That useful table gives elemental density in g/cm3:
aluminum = 2.7
iron = 7.9
lead = 11.4
gold = 19.32
tungsten = 19.35
osmium = 22.6
Can’t afford gold, not even I would put a lead slug in a kitchen knife, and I had the electrodes, so why not?
Waving a neodymium magnet over the handle convinced me that I could drill a hole slightly more than two inches deep without hitting the tang. I briefly considered drilling half a dozen smaller holes, but that started to look like a lot of work and I don’t have any suitable gun drills.
The business end of the electrode measures 1 inch long and 0.1375 inch in diameter. A hexagonal cluster of seven rods fits neatly into a round hole about 3×0.137 = 0.413 inch in diameter: quite conveniently a nice, long Z drill. So I clamped the knife between two strips in the drill press vise and had my way with it:
Drilling knife handle
Actually, I spot-drilled with a center drill, then used a long step drill, stopping with the 3/8 inch step just kissing the low side of the handle, to get the hole mostly on center, before running the Z drill down about 2-1/8 inch. The handle walls became so thin that they flexed around the drill to produce an undersized hole, so I reamed it with a hand-turned 7/16 inch drill and the electrodes fit with no room to spare:
Tungsten electrodes in knife handle
Yeah, that’s a crack in the top electrode: tungsten is brittle.
A dollop of epoxy atop the electrodes should seal them in place forever. I clamped the knife (in its color-matched scabbard) with the angled end of the handle water-level, so the epoxy settled in a neat, symmetric blob that looks better in person than it does here:
Epoxy seal over tungsten weights
The epoxy forms a plug over the ends of the electrodes and (probably) doesn’t extend very far down between them, but they’re firmly jammed in a snug hole and (probably) won’t ever rattle around.
Seven electrodes weighed 32 g and, figuring the missing plastic rounds off to slightly over nothing, the handle now has 60 g of additional weight out toward the end, producing a knife weighing 185 g that balances near the narrowest part of the handle. It’s somewhat heavier than I’d like, but I can cope.
The edge came from the factory reasonably sharp; a few passes over the sharpening steel touched it up nicely.
Early results: it cuts cheese perfectly, drifts to the right in melons, cuts wafer-thin slices from a loaf of my High-Traction Bread, and dismantles fruit with some clumsiness. Overall, I like it, although I could do without the bright green color in a big way.
Mary decided her cycling shoes were worn out after about four years and maybe 8000 miles. Walking with cleated shoes doesn’t work well (no, we don’t bother with cleat covers), but they’ve seen a few miles of pavement, too:
Worn SPD cleat in cycling shoe
A closeup shows that the surface of the old cleat really has worn away:
SPD cleats – new and worn
The rear tang is mostly there:
SPD cleats – rear tang
But the front tang is mostly gone:
SPD cleats – front tang
New shoes, new cleats, new pedals… we’re still tuning for best fit.
So I finally looked at why one of the trouser hangers made a nasty gritty noise. Turns out that, no suprise, when you rub steel against steel long enough, it wears away:
Trouser hanger – abraded steel
Another hanger had a huge roller that worked wonderfully well:
Trouser hanger – elaborate roller
That one was obviously over-engineered, but a simple roller also works well:
Trouser hanger – simple roller
They cheapnified this one just a bit too much, because it’s not quite a roller any more:
Trouser hanger – ineffective roller
A bit of rummaging turned up enough hangers with working rollers, so it’s all good now…
There I was, in the kitchen, minding my own business, when I felt something crawling up my shin…
Dog Tick – Ventral
It’s 5 mm from snout to rump, so it’s most likely a dog tick, not a deer tick, not that that makes me feel much better. It’s stuck to a strip of adhesive tape to prevent it from going anywhere and was flat enough to have not fed on anybody recently.
That picture didn’t require focus stacking, although I gave it a try anyway with inconclusive results. I must conjure up a much more rigid camera mount before that works well; a mini tripod isn’t good enough.
Something has gone badly wrong with the yellow bulk ink that I’m using in the Canon S630. Over the winter a precipitate formed in the bottles:
Sediment in ink bottles
And in the ink tanks:
Sediment in ink tank
But now that the Basement Laboratory has warmed up, not only does the precipitate remain, but some of it is growing:
Growth in ink tank
The picture doesn’t do it justice; it looks like pond scum in there. Only the yellow ink behaves like that, so it’s likely some contaminant in that batch. Because I buy ink in pint bottles, it’s a long time since that batch arrived and there’s no point in kvetching to the vendor. IIRC, I actually got this bottle from a friend who scrapped out his S630; he’d been refilling cartridges from the same source, too.
I ordered four sets of five tanks (CMYKK) from the usual eBay vendor for 20 bucks and will toss the old tanks & ink when those arrive.
There’s a set of four bulk ink bottles from a long-dead HP2000C printer on the shelf, but I suspect the ink chemistry differs by enough to ruin the Canon’s printhead… which is discontinued, so when the head dies, the printer dies, too.
The Smell of Molten Projects in the Morning 