Kenmore Progressive Vacuum Cleaner: Improved Suction Control

The Suction Control slider on the handle of our shiny new Kenmore Progressive vacuum cleaner varies the speed of the howling motor in the base unit, rather than venting more or less air into the pipe. We like that, but it’s all too easy to inadvertently slide the control and never notice it, sooo I marked the default condition:

Kenmore Progressive Vacuum - visible suction slider
Kenmore Progressive Vacuum – visible suction slider

Although every vacuum cleaner we’ve ever owned has touted its “quiet operation”, we always wear 30 dB ear muffs and it’s sometimes hard to tell the difference between full throttle and not quite so fast…

Bike Helmet Earbud Replacement

A bag arrived from halfway around the planet, bearing five sets of cheap earbuds. There was no way to tell from the eBay description, but they’re vented on the side:

Cheap earbud - side vent detail
Cheap earbud – side vent detail

And also to the rear, down inside those deep slots below the chromed plastic cover:

Cheap earbud - back openings
Cheap earbud – back openings

The raised lettering is a nice touch; the other earbud has a script L.

The PET braid over the fragile wire should withstand a bit more abuse than usual. The strain relief isn’t anything to cheer, though, consisting of that rectangular channel with the wire loose inside. I figured I’d start minimal and fix whatever crops up; I have nine more earbuds to go.

The motivation for all this was having the Gorilla Tape peel off the helmet, leaving a hardened mass of glue behind, then snagging the earbud wires. This is the new, somewhat better protected, wiring:

Bell Helmet - mic-earbud wire - hardened tape adhesive
Bell Helmet – mic-earbud wire – hardened tape adhesive

In a triumph of hope over experience, I applied more Gorilla Tape:

Bell Helmet - re-taped mic-earbud wiring
Bell Helmet – re-taped mic-earbud wiring

The helmet may need replacing after another iteration or two.

My solid modeling hand has become stronger these days, so I should gimmick up a flat-ish wart anchoring the mic boom and all the wiring to the helmet shell.

Command-line CD Ripping & Encoding

A recent and rather battered book-on-CD posed more than the usual problems for Asunder, so I finally broke down and fiddled around with cdparanoia and lame. This has obviously been done many times before, but breaking it into two simple steps per CD makes the inevitable errors easier to find and work around.

Invoke cdparanoia thusly to rip an entire CD into separate tracks:

cdparanoia -B -v

The files pop out sporting names like track01.cdda.wav, but they won’t be around long enough for you to develop a deep emotional attachment.

Throw a handful of parameters at lame to convert the WAV files into tagged MP3 files:

for t in {01..18} ; do lame --preset tape --tt "D${d}:T${t}" --ta "Author Name" --tl "Book title" --tn "${t}/18" --tg "Audio Book" --add-id3v2 track${t}.cdda.wav D${d}-${t}.mp3 ; done
rm track*

There’s surely a way to make a double substitution work in the track sequence, but the syntax, ah, escapes me at the moment.

You might want to not delete the WAV files until you’re happy with the MP3 results.

In any event, that produces a sequence of MP3 files imaginatively named along the lines of D1-01.mp3, which fits neatly into the cramped LCD space available on an MP3 player.

Your quality preferences may differ…

Slic3r vs. Sequential 3D Printing

The tiny posts on the fencing helmet ear grommet produced a remarkable amount of PETG hair, because the nozzle had to skip between four separate pieces on the platform at each layer:

So I told Slic3r to build each part separately:

Fencing helmet grommet - separate builds - first attempt
Fencing helmet grommet – separate builds – first attempt

Due to absolutely no forethought or planning on my part, that actually worked. Slic3r defines a cylindrical keep-out zone around the nozzle that I set to 15 mm radius and 25 mm height, but those numbers are completely wrong for the M2, particularly with a V4 hot end.

To the rear, the nuts & bolts along the bottom of the X gantry sit 5 mm above the V4 nozzle, with the relaxed actuator on my re-relocated Z-axis home switch at Z=+1 mm:

V4 PETG - extruder priming
V4 PETG – extruder priming

To the front, the bed fan doesn’t sit much higher:

M2 V4 Extruder - 24 V fans
M2 V4 Extruder – 24 V fans

As it turned out, the front washers built first, sitting there in front of the gantry and behind the fan, the rear washers appeared last, and Everything Just Worked.

However, even though the M2’s layout won’t allow for automated layout, I figured I could do it manually by building the parts from front to rear:

Fencing Helmet Ear Grommet - Slic3r layout
Fencing Helmet Ear Grommet – Slic3r layout

That way, the already-built parts never pass under the gantry / switch. For particularly tall parts, I could remove / relocate the bed fan to clear the already-built parts as they appear.

Come to find out that Slic3r, for whatever reason, doesn’t build the parts in the order you’d expect from the nice list on the far right side of the screen:

Sequential Build Order - Slic3r vs Pronterface
Sequential Build Order – Slic3r vs Pronterface

Worse, the Slic3r 3D preview shows the threads by layer (which is what you’d expect), rather than by object for sequential builds:

Slic3r - sequential preview vs build order
Slic3r – sequential preview vs build order

I don’t know how you’d force-fit a four-dimensional preview into the UI, so I won’t complain at all.

There’s no way to tell which part will build first; selecting the part will highlight its entry in the list (and vice versa), but the order of appearance in that list doesn’t tell you where the G-Code will appear in the output file. That’s not a problem for extruders with a keep-out volume that looks like a cylinder, so there’s no reason for Slic3r to do it any differently: it will manage the extruder position to clear all the objects in any order.

The Pronterface preview creates the objects by reading the G-Code file and displaying the threads in order, so, if you’re quick and it’s slow, you can watch the parts appear in their to-be-built order. The detailed preview (in the small window on the right in the screenshot) does show the parts in the order they will be built as you scroll upward through the “layers”, which is the only way you can tell what will happen.

So doing sequential builds requires iterating through these steps until the right answer appears:

  •  Add all objects separately to get each one as a separate line in the list to the right
    • Using the More option to duplicate objects produces multiple objects per line = Bad Idea
  • Arrange objects in a line from front to back
  • Export G-Code file
  • Load G-Code file into Pronterface
  • Pop up the Pronterface layer preview, scroll upward to show build order, note carefully
  • Rearrange parts in Slic3r accordingly

That’s do-able (note the different order from the Slic3r preview):

Fencing helmet grommet - manual sequential build
Fencing helmet grommet – manual sequential build

But it’s tedious and enough of a pain that it probably makes no sense for anything other than parts that you absolutely can’t build any other way.

In this case, completing each of the bottom washers separately eliminated all of the PETG hair between the small pegs. The upper washers still had some hair inside the inner cylinder, but not much. If you were fussy, you could suppress that by selecting “Avoid crossing perimeters”, at the cost of more flailing around in the XY plane.

All those spare grommets will make a good show-n-tell exhibit…

Family Christmas Ride

This doesn’t happen very often nowadays:

The Family That Rides Together - DCRT near Parker - 2015-12-25
The Family That Rides Together – DCRT near Parker – 2015-12-25

That’s in the rock cut just east of the tunnel under Parker Avenue. In a normal winter, that rock wall completely shadows the asphalt and preserves an icy layer through March.

We rode out-and-back over the Walkway, with a few digressions along the way:

Christmas Ride 2015 - APRS track
Christmas Ride 2015 – APRS track

A good ride was had by all; we could get used to those empty roads…


Copper Pipe Corrosion Pinholes

When we moved into this house, I noticed a hose clamp around the half-inch copper pipe carrying hard water to the toilets and kitchen sink:

Hose clamp patch on copper pipe
Hose clamp patch on copper pipe

That’s obviously a whole bunch easier than removing and replacing a section of copper pipe, so I’d say it was entirely justified. The fact that it hasn’t leaked for at least the last quarter century counts for something.

However, Mary recently discovered a small wet spot on the basement floor. Looking directly upward, we saw:

Copper pipe corrosion pinhole - 1
Copper pipe corrosion pinhole – 1

That was in open air; I added the marks around the corrosion to highlight it.

I’d applied some foam insulation on the supply end of the pipe and, just to check, peeled it back:

Copper pipe corrosion pinhole - 2
Copper pipe corrosion pinhole – 2

Huh. Although that leak was slow enough to not leak out of the insulation (the slit was upward), disturbing the corrosion produced a regular drip. Again, those marks are new.

OK, two active pinhole leaks and a small dry green spot further downstream says it’s finally time to replace that pipe. The lengths of pipe with the pinholes add up to about eight feet, which suggests the plumber installed a bad piece of pipe back in 1955.

Yes, I applied two more hose clamps for the holiday season, but that can’t last.

Having a good stock of tees, elbows, and unions on hand, all I need is 21 feet (not 20, alas) of shiny new copper pipe to replace the entire run containing all the pinholes; I’m not going to fiddle around replacing just a few sections.