Author: Ed

UDEV Rules for Cheap Numeric Keypads

I’m thinking of numeric keypads as control panels for Raspberry Pi projects like a simpleminded streaming radio player, so:

Sorta like wedding pictures: you can expose for the groom-in-black or the bride-in-white, but not both at the same time.

The wireless keypad does not have a slot for the USB radio: put ’em in a bag to keep ’em together when not in use.

The general idea is to create a standard name (/dev/input/keypad) for either keypad when it gets plugged in, so the program need not figure out the device name from first principles. This being an embedded system, I can ensure only one keypad will be plugged in at any one time.

The wired keypad has an odd name that makes a certain perverse sense:

cat /proc/bus/input/devices
... snippage ...
I: Bus=0003 Vendor=13ba Product=0001 Version=0110
N: Name="HID 13ba:0001"
P: Phys=usb-20980000.usb-1.4/input0
S: Sysfs=/devices/platform/soc/20980000.usb/usb1/1-1/1-1.4/1-1.4:1.0/0003:13BA:0001.0007/input/input6
U: Uniq=
H: Handlers=sysrq kbd event0
B: PROP=0
B: EV=120013
B: KEY=10000 7 ff800000 7ff febeffdf f3cfffff ffffffff fffffffe
B: MSC=10
B: LED=7

It’s a single-function device, so this rule in /etc/udev/rules.d/KeyPad.rules suffices:

ATTRS{name}=="HID 13ba:0001", SYMLINK+="input/keypad"

Using the Vendor and Device ID strings (13ba:0001) might make more sense.

The wireless keypad isn’t nearly that easy, because it reports for duty as both a keyboard and a mouse:

cat /proc/bus/input/devices
... snippage ...
I: Bus=0003 Vendor=062a Product=4101 Version=0110
N: Name="MOSART Semi. 2.4G Keyboard Mouse"
P: Phys=usb-20980000.usb-1.4/input0
S: Sysfs=/devices/platform/soc/20980000.usb/usb1/1-1/1-1.4/1-1.4:1.0/0003:062A:4101.0008/input/input7
U: Uniq=
H: Handlers=sysrq kbd event0
B: PROP=0
B: EV=120013
B: KEY=10000 7 ff9f207a c14057ff febeffdf ffefffff ffffffff fffffffe
B: MSC=10
B: LED=7

I: Bus=0003 Vendor=062a Product=4101 Version=0110
N: Name="MOSART Semi. 2.4G Keyboard Mouse"
P: Phys=usb-20980000.usb-1.4/input1
S: Sysfs=/devices/platform/soc/20980000.usb/usb1/1-1/1-1.4/1-1.4:1.1/0003:062A:4101.0009/input/input8
U: Uniq=
H: Handlers=kbd mouse0 event2
B: PROP=0
B: EV=1f
B: KEY=3f 3007f 0 0 0 0 483ffff 17aff32d bf544446 0 0 1f0001 130f93 8b17c000 677bfa d941dfed 9ed680 4400 0 10000002
B: REL=1c3
B: ABS=1f01 0
B: MSC=10

That may be because the 0x06a2 Vendor ID was cloned (that’s pronounced “ripped-off”) from Creative Labs. My guess is they ripped the entire chipset, because the 0x4101 device ID came from a Creative Labs wireless keyboard + mouse:

lsusb
... snippage ...
Bus 001 Device 011: ID 062a:4101 Creative Labs
... snippage ...

Because it’s a dual-mode wireless device, we need more information to create the corresponding udev rule. The keyboard part appears (on this boot) as event0, which we find thusly:

ll /dev/input/by-id
total 0
lrwxrwxrwx 1 root root 9 Feb  5 17:39 usb-Burr-Brown_from_TI_USB_Audio_CODEC-event-if03 -> ../event1
lrwxrwxrwx 1 root root 9 Feb  5 17:39 usb-MOSART_Semi._2.4G_Keyboard_Mouse-event-kbd -> ../event0
lrwxrwxrwx 1 root root 9 Feb  5 17:39 usb-MOSART_Semi._2.4G_Keyboard_Mouse-if01-event-mouse -> ../event2
lrwxrwxrwx 1 root root 9 Feb  5 17:39 usb-MOSART_Semi._2.4G_Keyboard_Mouse-if01-mouse -> ../mouse0

Some spelunking suggests using the environment variables set up by the default udev rules, which we find thusly:

udevadm test /sys/class/input/event0
... vast snippage ...
.INPUT_CLASS=kbd
ACTION=add
DEVLINKS=/dev/input/by-id/usb-MOSART_Semi._2.4G_Keyboard_Mouse-event-kbd /dev/input/by-path/platform-20980000.usb-usb-0:1.4:1.0-event-kbd
DEVNAME=/dev/input/event0
DEVPATH=/devices/platform/soc/20980000.usb/usb1/1-1/1-1.4/1-1.4:1.0/0003:062A:4101.0012/input/input17/event0
ID_BUS=usb
ID_INPUT=1
ID_INPUT_KEY=1
ID_INPUT_KEYBOARD=1
ID_MODEL=2.4G_Keyboard_Mouse
ID_MODEL_ENC=2.4G\x20Keyboard\x20Mouse
ID_MODEL_ID=4101
ID_PATH=platform-20980000.usb-usb-0:1.4:1.0
ID_PATH_TAG=platform-20980000_usb-usb-0_1_4_1_0
ID_REVISION=0108
ID_SERIAL=MOSART_Semi._2.4G_Keyboard_Mouse
ID_TYPE=hid
ID_USB_DRIVER=usbhid
ID_USB_INTERFACES=:030101:030102:
ID_USB_INTERFACE_NUM=00
ID_VENDOR=MOSART_Semi.
ID_VENDOR_ENC=MOSART\x20Semi.
ID_VENDOR_ID=062a
MAJOR=13
MINOR=64
SUBSYSTEM=input
... more snippage ...

So when that vendor and device appear with ID_INPUT_KEYBOARD set, we can create a useful symlink using this rule in /etc/udev/rules.d/KeyPad.rules:

ATTRS{idVendor}=="062a", ATTRS{idProduct}=="4101", ENV{ID_INPUT_KEYBOARD}=="1", SYMLINK+="input/keypad"

Because only one keypad will be plugged in at any one time, the /etc/udev/rules.d/KeyPad.rules file can contain both rules:

ATTRS{name}=="HID 13ba:0001", SYMLINK+="input/keypad"
ATTRS{idVendor}=="062a", ATTRS{idProduct}=="4101", ENV{ID_INPUT_KEYBOARD}=="1", SYMLINK+="input/keypad"

Reload the rules and fire them off:

sudo udevadm control --reload
sudo udevadm trigger

And then It Just Works:

ll /dev/input/by-id
total 0
lrwxrwxrwx 1 root root 9 Feb  5 17:39 usb-Burr-Brown_from_TI_USB_Audio_CODEC-event-if03 -> ../event1
lrwxrwxrwx 1 root root 9 Feb  5 19:03 usb-MOSART_Semi._2.4G_Keyboard_Mouse-event-kbd -> ../event0
lrwxrwxrwx 1 root root 9 Feb  5 19:03 usb-MOSART_Semi._2.4G_Keyboard_Mouse-if01-event-mouse -> ../event2
lrwxrwxrwx 1 root root 9 Feb  5 19:03 usb-MOSART_Semi._2.4G_Keyboard_Mouse-if01-mouse -> ../mouse0ll /dev/input

ll /dev/input
total 0
drwxr-xr-x 2 root root     120 Feb  5 19:03 by-id
drwxr-xr-x 2 root root     120 Feb  5 19:03 by-path
crw-rw---- 1 root input 13, 64 Feb  5 19:03 event0
crw-rw---- 1 root input 13, 65 Feb  5 17:39 event1
crw-rw---- 1 root input 13, 66 Feb  5 19:03 event2
lrwxrwxrwx 1 root root       6 Feb  5 19:03 keypad -> event0
crw-rw---- 1 root input 13, 63 Feb  5 17:39 mice
crw-rw---- 1 root input 13, 32 Feb  5 19:03 mouse0

My configuration hand is strong…

Note: Once again, I manually restored the source code after the WordPress “improved” editor shredded it by replacing all the double-quote and greater-than symbols inside the “protected” sourcecode blocks with their HTML-escaped equivalents. Some breakage may remain and, as always, WP can shred sourcecode blocks even if I don’t edit the post. They’ve (apparently) banned me from contacting Support, because of an intemperate rant based on years of having them ignore this (and other) problems. I didn’t expect any real help, so this isn’t much of a step backwards in terms of actual support …

2016-02-18

Removing Old Kernels
Mostly, I don’t worry about the accumulation of old kernels building up in /boot and sudo apt-get autoremove may scrub most of them, but sometimes it doesn’t when I’m doing something else and I must wade through the accumulation of old packages in Synaptic. Removing all those packages by hand gets tedious, but I’m reluctant to unleash a rarely used script on the clutter for fear of creating a worse problem.

The iterator in this burst of Bash line noise:
```
for f in $(ls /boot | grep vmlinuz | cut -d\- -f2,3 | sort | head -n -1) ; do dpkg -l | grep "^ii\ \ linux-" | grep $f | cut -d" " -f 3 >> /tmp/pkgs.txt ; done
```
… parses the list of kernels in /boot into version numbers, finds the corresponding installed packages, sorts them in ascending order, discards the last entry so as to not uninstall the most recent kernel, and passes each line of the resulting list into the loop.

N.B: The grep argument has two spaces after the ii that WordPress would destroy without the escaping backslashes. You can try "^ii linux-", but if the loop puts nothing in the file, that’s why.

Given each kernel version number, the loop extracts the package names from the installed kernel packages and glues the result onto a file that looks like this:
```
cat /tmp/pkgs.txt
linux-headers-3.13.0-73
linux-headers-3.13.0-73-generic
linux-image-3.13.0-73-generic
linux-image-extra-3.13.0-73-generic
linux-headers-3.13.0-74
linux-headers-3.13.0-74-generic
linux-image-3.13.0-74-generic
linux-image-extra-3.13.0-74-generic
linux-headers-3.13.0-76
linux-headers-3.13.0-76-generic
linux-image-3.13.0-76-generic
linux-image-extra-3.13.0-76-generic
```
Convert that file into a one-line string of package names and verify what would happen:
```
paste -s -d " " /tmp/pkgs.txt | xargs sudo apt-get --dry-run purge
```
If everything looks good, change --dry-run to --yes and blow ’em away.

No, I can’t possibly remember or type that gibberish by hand, but I do know where to find it…
2016-02-17
Knurled Inch Inserts
Tagging along behind the metric inserts, a sack of knurled brass inch-size screw inserts arrived:

Threaded Inserts – metric and inch

The nice stainless steel screws on the right range from 4-40 to 10-32, which suffice for nearly everything I build around here.

Unlike the splined metric inserts on the left, these inserts have actual knurls and ridges that should hold them firmly in place. The specs give hard-inch dimensions, of course, that (seem to) correspond to the root diameter of the knurls. You can find nice engineering drawings of precise tapered holes (by drilling down into the Heat-Set Inserts for Plastics item on that page), but a few metric measurements of the actual parts on hand should suffice for my simple needs.

Thread: overall length x small rim OD x (knurl length x larger knurl OD)
- 4-40: 5.8 x 3.9 x (4.0 x 4.6)
- 6-32: 7.1 x 4.7 x (4.6 x 5.5)
- 8-32: 8.1 x 5.5 x (5.9 x 6.3)
- 10-32: 9.5 x 6.3 x (7.0 x 7.1)
Rather than fussing with a tapered hole, just punch a cylinder with the small rim OD (to clear the screw) through the part and put a cylinder with the knurl OD x length at the surface.

Using cylinders without diameter correction will make them slightly undersized for heat bonding. The usual 3D printing tolerances don’t justify anything fussier than that.

Using PolyCyl diameter correction will make the holes nearly spot on for epoxy bonding: butter ’em up, ram ’em in, pause for curing, done.

That’s the plan, anyhow…
2016-02-16
Monthly Image: Frost Growth

The northeast vent on the well pit grew an ice rim during the same night that frosted the roofing nails:

Well Pit Vent Frost

The other vent remained clear, so the prevailing breeze definitely goes in one hole and out the other:

Well Pit Vent Frost – inlet

Well Pit Vent Frost – inlet

A waterproof Hobo datalogger hangs from the string.

2016-02-15
Self-Cleaning Bird Nest Box

We celebrate the start of Spring by cleaning the previous season’s nest(s) from our bird boxes, so this “improved” design caught our eye on a walk around the neighborhood:

Self-cleaning bird nest box

Birds being the way they are, the most recent occupants surely piled more twigs & grass atop their foundation to make the level come out right. An industrious mouse might find a convenient route inside.

2016-02-14
Autodesk Privacy Statement: “Do Not Track” and Similar Mechanisms

Autodesk just Borged Netfabb and, in the process of merging their address lists, asked me to update my info and agree to their very detailed Privacy Statement. You should take a look at it; the link will open in a new tab / window / whatever, so you don’t lose your place here.

Have you noticed how those “statements” always have a very long and firmly fixed line width that doesn’t adapt to your window size, use various shades of light-gray-on-white typefaces in the smallest sizes, and continue for pages and pages. I don’t believe in coincidences, either.

Here’s what they think of my Do Not Track browser setting (emphasis added):

“Do not track” and similar mechanisms

Some web browsers may transmit “do-not-track” signals to websites with which the browser communicates. Because of differences in how web browsers incorporate and activate this feature, it is not always clear whether users intend for these signals to be transmitted, or whether they are even aware of them.

Participants in the leading Internet standards-setting organization that is addressing this issue are in the process of determining what, if anything, websites should do when they receive such signals. Autodesk currently does not take action in response to these signals. If and when a final standard is established and accepted, we will reassess how to respond to these signals.

For information about cookies, web beacons and similar technologies, please read our Cookie Policy.

After plowing through much of their “statement”, I decided Autodesk doesn’t do anything I need to know about and, seeing as how Netfabb gradually faded from my attention when their web service joined Microsoft’s Azure cloud, I declined to “confirm my preferences” and didn’t click the big blue button. I doubt such inaction will remove my email address from their list, but it’s the only choice they offer.

Because I can’t tell if a website really wants to track me, I block ads, disable Flash, and destroy all cookies when I leave their site, Just In Case they inadvertently deployed all that crap. I’m sure they never intend to serve malware through an ad slot brokered on their site, but mistakes do happen, and I’m glad to assist them.

If you’re seeing ads on this page right now, they come from WordPress and I get a small cut. You should start using an ad blocker right now; if your browser doesn’t permit you to block ads, change browsers. If you worry that reducing my advertising revenue will compromise the quality and quantity of what you see here, send me a sack of money through Paypal. Fair enough?

Also: Linux, dammit.

2016-02-13

Vacuum Tube LEDs: Ersatz Heat Sink Plate Cap

I wanted a slightly larger “plate cap” to fit a big incandescent bulb and it seemed a fake heatsink might add gravitas to the proceedings:

Vacuum Tube LEDs - large incandescent bulb — Vacuum Tube LEDs – large incandescent bulb

Yeah, that antique ceramic socket holds the bulb at a rakish angle. Worse, even though I painstakingly laid out the position of the heatsink atop the bulb, it’s visibly off-center. Which wouldn’t be so bad, had I not epoxied the damn thing in place.

After reaming out the M2’s filament drive, the entire blue base printed without incident.

A closer look at the cap:

Vacuum Tube LEDs - ersatz heatsink plate cap — Vacuum Tube LEDs – ersatz heatsink plate cap

Memo to Self: Next time, line it up with the vertical glass support inside the bulb and ignore the external evidence.

The boss has a hole for the braid-enclosed cable to the knockoff Neopixel:

Vacuum Tube Lights - finned cap - Slic3r preview — Vacuum Tube Lights – finned cap – Slic3r preview

The cupped surface perfectly fits the bulb’s 3.75 inch diameter. While you wouldn’t mill out a real heatsink, it definitely looks better this way and (alas) gives the epoxy more footprint for a better grip.

I built the fins with a 1/8 inch cutter in mind, so the fin root radius allows for a G3/G3 arc without gouging. I doubt machining a fake heatsink from aluminum makes any sense, but the cheap extruded heatsinks on eBay don’t look very good. Plus, they sport completely unnecessary tapped holes for LED mounts and suchlike.

A cross-section shows the wiring channel and cable entry:

Vacuum Tube Lights - fin cap solid model - section — Vacuum Tube Lights – fin cap solid model – section

I epoxied the Neopixel in place, applied double-sided carpet tape to the whole thing, then painstakingly trimmed around the fins with an Xacto knife:

Vacuum Tube LEDs - Ersatz Heatsink plate cap - tape — Vacuum Tube LEDs – Ersatz Heatsink plate cap – tape

That looked better from the top side (where it was completely hidden) and came heartbreakingly close to working, but after about a day the cable + braid put enough torque on the cap to peel it off the bulb. Obviously, the tape holds much less enthusiastically after that.

Part of the problem came from the cable’s rather sharp angle just outside the cap:

Vacuum Tube LEDs - Ersatz Heatink plate cap - detail — Vacuum Tube LEDs – Ersatz Heatink plate cap – detail

Rakish angle, indeed. Two of ’em, in fact.

Unlike the smaller cap on the halogen bulb, this time I didn’t bother with a brass tube ferrule, mostly to see how it looks. I think it came out OK and the black braid looks striking in person. Conversely, a touch of brass never detracts from the appearance.

Obviously, the cable wasn’t long enough, either. Part of that problem came from underestimating the braid length: it shortens dramatically when slipped over the cable, even when you expect shortening. Somehow I managed to overlook that, despite cutting the cable quite long enough, thankyouverymuch. There’s a tradeoff between gentle angles and having the cable stick out too far for comfort.

Memo to Self: Use a cable at least four inches longer than necessary, measure the combined cable + braid assembly after screwing the bulb in the socket, and don’t epoxy anything before all the parts are ready for assembly.

That’s why it’s a prototype made out of blue PETG…

Protip: running old ceramic sockets through the dishwasher greatly simplifies their subsequent cleanup.

All in all, I like it.

The OpenSCAD source code as a GitHub gist:

	// Vacuum Tube LED Lights
	// Ed Nisley KE4ZNU January 2016

	Layout = "FinCap"; // Cap LampBase USBPort Socket(s) (Build)FinCap

	Section = true; // cross-section the object

	Support = true;

	//- Extrusion parameters must match reality!

	ThreadThick = 0.25;
	ThreadWidth = 0.40;

	HoleWindage = 0.2;

	Protrusion = 0.1; // make holes end cleanly

	inch = 25.4;

	function IntegerMultiple(Size,Unit) = Unit * ceil(Size / Unit);

	//———————-
	// Dimensions
	// https://en.wikipedia.org/wiki/Tube_socket#Summary_of_Base_Details

	T_NAME = 0; // common name
	T_NUMPINS = 1; // total, with no allowance for keying
	T_PINBCD = 2; // tube pin circle diameter
	T_PINOD = 3; // … diameter
	T_PINLEN = 4; // … length (overestimate)
	T_HOLEOD = 5; // nominal panel hole from various sources
	T_PUNCHOD = 6; // panel hole optimized for inch-size Greenlee punches
	T_TUBEOD = 7; // envelope or base diameter
	T_PIPEOD = 8; // light pipe from LED to tube base
	T_SCREWOC = 9; // mounting screw holes

	// Name pins BCD dia length hole punch env pipe screw
	TubeData = [
	["Mini7", 8, 9.53, 1.016, 7.0, 16.0, 11/16 * inch, 18.0, 5.0, 22.5],
	["Octal", 8, 17.45, 2.36, 10.0, 36.2, (8 + 1)/8 * inch, 32.0, 11.5, 39.0],
	["Noval", 10, 11.89, 1.1016, 7.0, 22.0, 7/8 * inch, 21.0, 5.0, 28.0],
	["Duodecar", 13, 19.10, 1.05, 9.0, 32.0, 1.25 * inch, 38.0, 12.5, 39.0],
	];

	ID = 0;
	OD = 1;
	LENGTH = 2;

	Pixel = [7.0,10.0,3.0]; // ID = contact patch, OD = PCB dia, LENGTH = overall thickness

	Nut = [3.5,8.0,3.0]; // socket mounting nut recess

	BaseShim = 2*ThreadThick; // between pin holes and pixel top
	SocketFlange = 2.0; // rim around socket below punchout
	PanelThick = 2.0; // socket extension through punchout

	//———————-
	// 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);
	}

	//———————-
	// Tube cap

	CapTube = [4.0,3/16 * inch,10.0]; // brass tube for flying lead to cap LED

	CapSize = [Pixel[ID],(Pixel[OD] + 3.0),(CapTube[OD] + 2*Pixel[LENGTH])];

	CapSides = 6*4;

	module Cap() {

	difference() {
	union() {
	cylinder(d=CapSize[OD],h=(CapSize[LENGTH]),$fn=CapSides); // main cap body
	translate([0,0,CapSize[LENGTH]]) // rounded top
	scale([1.0,1.0,0.65])
	sphere(d=CapSize[OD]/cos(180/CapSides),$fn=CapSides); // cos() fixes slight undersize vs cylinder
	cylinder(d1=(CapSize[OD] + 23ThreadWidth),d2=CapSize[OD],h=1.5*Pixel[LENGTH],$fn=CapSides); // skirt
	}

	translate([0,0,-Protrusion]) // bore for wiring to LED
	PolyCyl(CapSize[ID],(CapSize[LENGTH] + 3*ThreadThick + Protrusion),CapSides);

	translate([0,0,-Protrusion]) // PCB recess with clearance for tube dome
	PolyCyl(Pixel[OD],(1.5*Pixel[LENGTH] + Protrusion),CapSides);

	translate([0,0,(1.5*Pixel[LENGTH] – Protrusion)]) // small step + cone to retain PCB
	cylinder(d1=(Pixel[OD]/cos(180/CapSides)),d2=Pixel[ID],h=(Pixel[LENGTH] + Protrusion),$fn=CapSides);

	translate([0,0,(CapSize[LENGTH] – CapTube[OD]/(2*cos(180/8)))]) // hole for brass tube holding wire loom
	rotate([90,0,0]) rotate(180/8)
	PolyCyl(CapTube[OD],CapSize[OD],8);
	}

	}

	//———————-
	// Heatsink tube cap

	CableOD = 3.5; // cable + braid diameter
	BulbOD = 3.75 * inch; // bulb OD; use 10 inches for flat

	FinCutterOD = 1/8 * inch;
	echo(str("Fin Cutter: ",FinCutterOD));
	FinSides = 2*4;

	FinCapSize = [(Pixel[OD] + 2FinCutterOD),30.0,(10.0 + 2Pixel[LENGTH])];

	BulbRadius = BulbOD / 2;
	BulbDepth = BulbRadius – sqrt(pow(BulbRadius,2) – pow(FinCapSize[OD],2)/4);
	echo(str("Bulb OD: ",BulbOD," recess: ",BulbDepth));

	module FinCap() {

	NumFins = floor(PIFinCapSize[ID] / (2FinCutterOD));
	FinAngle = 360 / NumFins;
	echo(str("NumFins: ",NumFins," angle: ",FinAngle," deg"));

	difference() {
	union() {
	cylinder(d=FinCapSize[ID],h=FinCapSize[LENGTH],$fn=2*NumFins); // main body

	for (i = [0:NumFins – 1]) // fins
	rotate(i * FinAngle)
	hull() {
	translate([FinCapSize[ID]/2,0,0])
	rotate(180/FinSides)
	cylinder(d=FinCutterOD,h=FinCapSize[LENGTH],$fn=FinSides);
	translate([(FinCapSize[OD] – FinCutterOD)/2,0,0])
	rotate(180/FinSides)
	cylinder(d=FinCutterOD,h=FinCapSize[LENGTH],$fn=FinSides);
	}

	rotate(FinAngle/2) // cable entry boss
	translate([FinCapSize[ID]/2,0,FinCapSize[LENGTH]/2])
	cube([FinCapSize[OD]/4,FinCapSize[OD]/4,FinCapSize[LENGTH]],center=true);
	}

	for (i = [1:NumFins – 1]) // fin inner gullets, omit cable entry side
	rotate(i * FinAngle + FinAngle/2) // joint isn't quite perfect, but OK
	translate([FinCapSize[ID]/2,0,-Protrusion])
	rotate(0*180/FinSides)
	cylinder(d=FinCutterOD/cos(180/FinSides),h=(FinCapSize[LENGTH] + 2*Protrusion),$fn=FinSides);

	translate([0,0,-Protrusion]) // PCB recess
	PolyCyl(Pixel[OD],(1.5*Pixel[LENGTH] + Protrusion),FinSides);

	PolyCyl(Pixel[ID],(FinCapSize[LENGTH] – 3*ThreadThick),FinSides); // bore for LED wiring

	translate([0,0,(FinCapSize[LENGTH] – 3ThreadThick – 2CableOD/(2*cos(180/8)))]) // cable inlet
	rotate(FinAngle/2) rotate([0,90,0]) rotate(180/8)
	PolyCyl(CableOD,FinCapSize[OD],8);

	if (BulbOD <= 10.0 * inch) // curve for top of bulb
	translate([0,0,-(BulbRadius – BulbDepth + 2*ThreadThick)]) // … slightly flatten tips
	sphere(d=BulbOD,$fn=16*FinSides);
	}

	}


	//———————-
	// Aperture for USB-to-serial adapter snout
	// These are all magic numbers, of course

	module USBPort() {

	translate([0,28.0])
	rotate([90,0,0])
	linear_extrude(height=28.0)
	polygon(points=[
	[0,0],
	[8.0,0],
	[8.0,4.0],
	// [4.0,4.0],
	[4.0,6.5],
	[-4.0,6.5],
	// [-4.0,4.0],
	[-8.0,4.0],
	[-8.0,0],
	]);
	}


	//———————-
	// Box for Leviton ceramic lamp base

	module LampBase() {

	Bottom = 3.0;
	Base = [4.0inch,4.5inch,20.0 + Bottom];
	Sides = 12*4;

	Retainer = [3.5,11.0,1.0]; // flat fiber washer holding lamp base screws in place

	StudSides = 8;
	StudOC = 3.5 * inch;
	Stud = [0.107 * inch, // 6-32 mounting screws
	min(15.0,1.5*(Base[ID] – StudOC)/cos(180/StudSides)), // OD = big enough to merge with walls
	(Base[LENGTH] – Retainer[LENGTH])]; // leave room for retainer


	union() {
	difference() {
	rotate(180/Sides)
	cylinder(d=Base[OD],h=Base[LENGTH],$fn=Sides);
	rotate(180/Sides)
	translate([0,0,Bottom])
	cylinder(d=Base[ID],h=Base[LENGTH],$fn=Sides);
	translate([0,-Base[OD]/2,Bottom + 1.2]) // mount on double-sided foam tape
	rotate(0)
	USBPort();
	}
	for (i = [-1,1])
	translate([i*StudOC/2,0,0])
	rotate(180/StudSides)
	difference() {
	# cylinder(d=Stud[OD],h=Stud[LENGTH],$fn=StudSides);
	translate([0,0,Bottom])
	PolyCyl(Stud[ID],(Stud[LENGTH] – (Bottom – Protrusion)),6);
	}
	}
	}

	//———————-
	// Tube Socket

	module Socket(Name = "Mini7") {

	NumSides = 6*4;

	Tube = search([Name],TubeData,1,0)[0];
	echo(str("Building ",TubeData[Tube][0]," socket"));
	echo(str(" Punch: ",TubeData[ID][T_PUNCHOD]," mm = ",TubeData[ID][T_PUNCHOD]/inch," inch"));
	echo(str(" Screws: ",TubeData[ID][T_SCREWOC]," mm =",TubeData[ID][T_SCREWOC]/inch," inch OC"));

	OAH = Pixel[LENGTH] + BaseShim + TubeData[Tube][T_PINLEN];
	BaseHeight = OAH – PanelThick;

	difference() {
	union() {
	linear_extrude(height=BaseHeight)
	hull() {
	circle(d=(TubeData[Tube][T_PUNCHOD] + 2*SocketFlange),$fn=NumSides);
	for (i=[-1,1])
	translate([i*TubeData[Tube][T_SCREWOC]/2,0])
	circle(d=2*Nut[OD],$fn=NumSides);
	}
	cylinder(d=TubeData[Tube][T_PUNCHOD],h=OAH,$fn=NumSides);
	}

	for (i=[0:(TubeData[Tube][T_NUMPINS] – 1)]) // tube pins
	rotate(i*360/TubeData[Tube][T_NUMPINS])
	translate([TubeData[Tube][T_PINBCD]/2,0,(OAH – TubeData[Tube][T_PINLEN])])
	rotate(180/4)
	PolyCyl(TubeData[Tube][T_PINOD],(TubeData[Tube][T_PINLEN] + Protrusion),4);

	for (i=[-1,1]) // mounting screw holes & nut traps
	translate([i*TubeData[Tube][T_SCREWOC]/2,0,-Protrusion]) {
	PolyCyl(Nut[OD],(Nut[LENGTH] + Protrusion),6);
	PolyCyl(Nut[ID],(OAH + 2*Protrusion),6);
	}

	translate([0,0,-Protrusion]) { // LED recess
	PolyCyl(Pixel[OD],(Pixel[LENGTH] + Protrusion),8);
	}

	translate([0,0,(Pixel[LENGTH] – Protrusion)]) { // light pipe
	rotate(180/TubeData[Tube][T_NUMPINS])
	PolyCyl(TubeData[Tube][T_PIPEOD],(OAH + 2*Protrusion),TubeData[Tube][T_NUMPINS]);
	}
	}

	// Totally ad-hoc support structures …

	if (Support) {
	color("Yellow") {
	for (i=[-1,1]) // nut traps
	translate([i*TubeData[Tube][T_SCREWOC]/2,0,(Nut[LENGTH] – ThreadThick)/2])
	for (a=[0:5])
	rotate(a*30 + 15)
	cube([2ThreadWidth,0.9Nut[OD],(Nut[LENGTH] – ThreadThick)],center=true);

	if (Pixel[OD] > TubeData[Tube][T_PIPEOD]) // support pipe only if needed
	translate([0,0,(Pixel[LENGTH] – ThreadThick)/2])
	for (a=[0:7])
	rotate(a*22.5)
	cube([2ThreadWidth,0.9Pixel[OD],(Pixel[LENGTH] – ThreadThick)],center=true);

	}
	}

	}

	//———————-
	// Build it

	if (Layout == "Cap") {
	if (Section)
	difference() {
	Cap();
	translate([-CapSize[OD],0,CapSize[LENGTH]])
	cube([2CapSize[OD],2CapSize[OD],3*CapSize[LENGTH]],center=true);
	}
	else
	Cap();
	}

	if (Layout == "FinCap") {
	if (Section) render(convexity=5)
	difference() {
	FinCap();
	// translate([0,-FinCapSize[OD],FinCapSize[LENGTH]])
	// cube([2FinCapSize[OD],2FinCapSize[OD],3*FinCapSize[LENGTH]],center=true);
	translate([-FinCapSize[OD],0,FinCapSize[LENGTH]])
	cube([2FinCapSize[OD],2FinCapSize[OD],3*FinCapSize[LENGTH]],center=true);
	}
	else
	FinCap();
	}

	if (Layout == "BuildFinCap")
	translate([0,0,FinCapSize[LENGTH]])
	rotate([180,0,0])
	FinCap();

	if (Layout == "LampBase")
	LampBase();

	if (Layout == "USBPort")
	USBPort();

	if (Layout == "Socket")
	if (Section) {
	difference() {
	Socket();
	translate([-100/2,0,-Protrusion])
	cube([100,50,50],center=false);
	}
	}
	else
	Socket();

	if (Layout == "Sockets") {
	translate([0,50,0])
	Socket("Mini7");
	translate([0,20,0])
	Socket("Octal");
	translate([0,-15,0])
	Socket("Duodecar");
	translate([0,-50,0])
	Socket("Noval");
	}

view raw Vacuum Tube Lights.scad hosted with ❤ by GitHub

2016-02-12

Author: Ed

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Vacuum Tube LEDs: Ersatz Heat Sink Plate Cap