Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.
For years this bottle of DeoxIT has been covered with a very thin layer of red juice, despite having the lid screwed firmly in place and a cap (removed here) pushed over the tube:
Caig DeoxIT bottle – lid crack repair
Turns out that there’s a minute crack in the cap. Every time I use the bottle, I refresh the oil layer on the inside of the bottle, which then gets pumped outside through capillary action. I’d been keeping the bottle in a tall ziploc baggie, specifically to contain the oil, and always assumed it was a simple leak.
The bottle still contains a lifetime supply of DeoxIT that may become a cherished family heirloom, one to be handed down through the generations. I can’t think of a better applicator, either, so I’m kind of stuck with that cap.
The cap is, of course, un-bondable polyethylene covered with thin oil, so there’s no possible way to repair it. I wiped it down with alcohol and acetone, then quick-like-a-bunny dabbed on a blob of Duco cement (which is the irregular shape on the cap) and worked it into the crack, in the hope it would stick well enough to reduce the pumping.
The springs balancing the dishwasher door started twanging again, which I now know is the diagnostic sign that an asphalt sound deadening sheet has slipped off the tub. A sheet on the right side almost perpetrated a clean escape, but the flap drooping over the spring gave it away:
Dishwasher sound deadener – slipped away
Another sheet on the left side was inching away, but hadn’t quite gotten over the fence:
Dishwasher sound deadener – slipping away
They’re pretty much a rigid solid at room temperature:
It puts one in mind of the pitch drop experiments now running in various labs. In this case, we now know it takes about four years for an asphalt sheet to slide completely off the tub; those two sheets were definitely in place when I buttoned it up after the previous one broke free.
I applied a heat gun to soften the sheets, then smoothed them around the tub again. This time I applied long strips of Gorilla Tape from one side to the other, rather than short strips of ordinary duct tape along the edges, and maybe this fix will outlast either the dishwasher or our tenure here, whichever comes first…
The new-to-me Optiplex 980 has a tool-free clamp securing the PCI card brackets to the chassis, with a nice plastic dress cover that really finishes off that side of the case. Alas, it’s secured by five small heat-staked plastic pegs that I managed to shear off as part of a finger fumble that you’ll recognize when it happens to you and which I need not further discuss:
Optiplex 980 PCI Clamp Cover – disassembled
So I drilled two slightly undersized holes for the tiniest screws in the Little Box o’ Tiny Screws:
Optiplex 980 PCI Clamp Cover – drilling
The two end plates sticking up are the only square parts of the cover, so that thing is actually clamped by the right-side plate and sheer will power. I ran the drill down 3 mm from the top of the post at the slowest manual jog speed from the Joggy Thing and I did not break through the top and did not hit that lathe bit under the cover.
The screw threads and a dab of epoxy hold them in place:
Optiplex 980 PCI Clamp Cover – tiny screws
I’d like to say the finished repair looked like this:
Optiplex 980 PCI Clamp Cover – in place
But, alas, the eagle-eyed reader will note that the screws are gone, replaced by two dabs of clear acrylic caulk; those faint threads and epoxy were no match for the snap of that latching lever and the slight distortion caused by the spring fingers applying force to the brackets.
Part of the routine cleaning around here involves running the vacuum cleaner nozzle over the keyboard to suck up random debris, but that doesn’t extract crud from under the keycaps. Almost exactly three years after the previous cleaning, I finally decided the keys had lost enough of their normal feel to justify the hassle of taking the thing apart.
Bolstered by that experience, however, I just yanked the keycaps off with a removal tool from my old bag of tricks, revealing the horror that lies beneath the surface:
The keycaps took a swim in a dishpan full of hot soapy water, endured some scrubbing, and emerged looking like new. Thwacking them on a towel ejected the remaining water from the posts.
With the electronics still in place, I vacuumed the larger chunks out of the tray, scrubbed the aforementioned hot soapy water around the bushings with an acid brush, then cleaned up the residue with cotton swabs. There’s a paper towel under the drain gutters to catch the runoff, which worked surprisingly well.
The keycap legends have been eroding, as they’re basically a decal stuck on the surface. Eventually I’ll have a crappy non-clicky Das Keyboard Model S Ultimate.
[Update: a spammer’s script has been attempting to create hundreds of junk comments per day, so I’ve temporarily disabled comments for this post. Drop me a direct note using the About / Copyright / Contact link on the right if it’s critical. I expect this to pass in a few days, but I may be underestimating the stupidity out there. ]
A note from regular commenter Frans:
Don’t get a Das Keyboard if you want a keyboard without a keypad. Look into e.g. a Leopold Tenkeyless Otaku. The one to which I include a link comes with the same Cherry MX Brown switches as the Das Keyboard Silent.
Those simple floor brush strips for the Samsung vacuum cleaner worked moderately well, but the urethane adhesive didn’t have enough grip on the plastic strips. Having just run out of that batch, I made up another set with slightly undercut holes:
Bushing Solid Model – better holes – bottom
That’s half a thread width on each side, just enough to give the adhesive something to grab. Such is the plan, anyway.
I taped the strips to a pair of credit cards (actually, flat cards without embossed characters), slathered a thin layer of urethane atop them, and laid on squares of the same wool fabric I used the last time:
Samsung vacuum floor strips – gluing
Then I piled a steel block atop an aluminum slab on both arrays, fast forwarded a day, peeled and flexed and cut the strips apart:
Samsung floor brushes – glued
The urethane foamed through the holes as I hoped and (seems to have) locked the fabric in place, at least well enough to withstand some experimental bending on the workbench.
Now, to see how they stand up to actual use…
The OpenSCAD source code:
// Samsung Vacuum cleaner nozzle floor strips
// Ed Nisley KE4ZNU January 2013
// November 2013 - adapt to M2, enlarge holes
Layout = "Build"; // Show, Build
//- Extrusion parameters must match reality!
// Print with +0 shells and 3 solid layers
ThreadThick = 0.25;
ThreadWidth = 0.4;
HoleWindage = 0.75;
function IntegerMultiple(Size,Unit) = Unit * ceil(Size / Unit);
Protrusion = 0.1; // make holes end cleanly
//----------------------
// Dimensions
Body = [6.0,59.0,3*ThreadThick]; // width, length, thick
Tab1 = [4.5,5.0,0.0]; // width, length, offset from centerline
Tab2 = [3.5,5.0,0.5];
HoleOC = 8.0; // adhesive anchoring holes
HoleDia = 2.0;
HoleSides = 4;
HoleMax = floor(Body[1]/(2*HoleOC));
echo("HoleMax: ",HoleMax);
//----------------------
// 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);
}
module BackingStrip() {
difference() {
union() {
translate([0,0,Body[2]/2])
cube(Body,center=true);
translate([Tab1[2],-1*Body[1]/2,Body[2]/2])
cube([Tab1[0],2*Tab1[1],Body[2]],center=true);
translate([Tab2[2],+1*Body[1]/2,Body[2]/2])
cube([Tab2[0],2*Tab2[1],Body[2]],center=true);
}
for (i = [-HoleMax:HoleMax])
translate([0,i*HoleOC,-Protrusion])
rotate(45) {
PolyCyl(HoleDia,(Body[2] + 2*Protrusion),HoleSides);
PolyCyl((HoleDia + ThreadWidth),(ThreadThick + Protrusion),HoleSides);
}
}
}
//----------------------
// Build it!
ShowPegGrid();
if (Layout == "Show")
BackingStrip();
if (Layout == "Build")
rotate(90) BackingStrip();
We don’t drive the van nearly often enough (*) to keep the battery charged in cold weather, so I use a trickle charger to keep it alive between jaunts. While opening the hood one evening, I managed to twist the plastic fitting that anchors the hood prop rod beyond its limits and snapped the poor thing off, which left me holding the hood in one hand and the rod in the other.
After extricating most of the fragments from under the van, I found that the OEM part had a hollow post that snapped into a square hole in the front bulkhead under the hood. The post had two keys and a pair of snap latches that held it in place, a design that seemed optimized for rapid assembly with no fiddly parts, but which depended on a few millimeters of plastic to restrain a meter of steel rod.
I made up a simple replacement with a solid square post and a square cap to clamp it against the bulkhead:
Toyota Sienna hood rod pivot – first version
The general idea is that the screw puts the entire post under compression, giving it less temptation to shear at the deck line when I twist the rod a bit too far out of line. That 8-32 screw seemed entirely adequate to the task; a 10-32 screw would take up too much of the post for my liking.
Alas, it turns out that underneath the bulkhead’s top flange lies a metal plate surrounding the headlight that’s so close to the hole that the big blocky cap wouldn’t fit. So I slimmed the cap down to three thread widths and tried again, only to discover that the plate came that close to the edge of square hole.
However, there was a gap between the bottom of the bulkhead and the top of the plate, so I introduced pivot and cap to Mr Belt Sander, removed enough plastic to let the cap slide into the gap, then discovered the 8-32 screw head was just slightly too large to let the screw align with the post.
Another tweak to the model, based on actual measurements on the abused parts, produced the final version:
Toyota Sienna Hood Rod Pivot – solid model
The rod hole has a nice bevel, there’s no fragile neck between the rod hole and the base flange, the solid post lies flat on the platform for EZ building, and there’s a slight offset between the post and the flange that eliminates the need for support material. Printing it lying down orients the filament paths around the hole and base, making the part stronger in the direction it needs the most strength.
I think the cap walls could be slightly thicker, but we’ll see how long the thing lasts…
A group photo of all the versions, lined up from left to right, shows the broken OEM part, the first blocky attempt, the slimmed-down and too-long version to the rear, the shorter version that actually fit, and a backup part for when that one breaks:
Toyota Sienna hood rod pivot versions
The sanded-down part held the hood open while I took that group picture. Here’s what it looks like under load:
Toyota Sienna hood rod pivot – in place
The scrawls on the bulkhead just in front of the pivot remind me of fluid levels, torques, and suchlike. The stud sticking out to the rear is a headlight aiming screw mounted in the plate that caused so much hassle; you’d think I’d have noticed it before starting this adventure, but noooo…
For what it’s worth, that’s rapid prototyping in action: three (and a half) iterations in quick succession, each getting closer to a goal that you (well, I) can’t quite define, but will recognize when it appears. Took about three hours over the course of two days.
I loves me my M2 3D printer…
(*) Indeed, the tires often take three miles to warm up their flat spots due to sitting in the garage for a week…
The Smell of Molten Projects in the Morning 