The Smell of Molten Projects in the Morning

Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.

Category: Oddities

Who’d’a thunk it?

Bent Tap: Huh?

The Shapeways bronze-infused stainless steel process reportedly produces objects so hard that they require carbide tooling, so I wasn’t too surprised when this magazine block rounded the threads right off a tap:

Browning Hi-Power magazine – steel block trial fit

The tap turned up while I was clearing off the bench and, seeing as how the upper half of the threads weren’t ruined, I thought maybe I could at least get a bottoming tap out of it.

Step 1: snap off the damaged part. This should be easy, as tap steel tends to punish you when you’re not doing it right. So I grabbed the ruined section in the bench vise and gave the shank a stiff whack:

Bent tap

Now, that is not a nominal outcome…

The tap came from a set of dubious provenance that’s conspicuously labeled: JUNK METRIC. I have no idea where it came from, as it’s slightly younger than dirt. There’s a Craftsman metric set in the same drawer with much better steel (yes, I’ve snapped a few taps) that I normally use; I figured if I was going to wreck a tap on that magazine block, I should wreck a junk tap.

Maybe that Shapeways stainless isn’t quite as nasty as it seems…

2014-01-25
Unsealed Camera Box

Used to be, back in the day, that when you got a box full of shiny new electronics, it bore stickers: “Do not accept if seal is broken” or “Factory sealed” or “Genuine product” or something like that. When you slit the seal, you had some confidence that the last person to look in the box sat at the end of their production line; I’ll grant you that counterfeit stickers have become cheap & readily available, but it’s the principle of the thing.

Nowadays, a shiny new Canon camera arrives in a box with a tab tucked into a slit:

Canon Camera box – unopened and unsealed

The box looked unopened and everything inside seemed in order, but … even though I’d seen this before on other cameras, it’s still disconcerting.

I’m unsure of the story about laminate flooring in the camera box.

2014-01-18
MHV LUG Lightning Talk: Intro to NSA Hardware Implants

Meme – Nixon – I see what you did there – 5x38k

I did five minutes of standup comedy at yesterday’s MHV Lug meeting, pointing out some of the more interesting ways to compromise a PC when you have an infinite budget for development and consumables.

You don’t get my patter with the PDF (unless you had access to the room’s bugging hardware), but the links may come in handy in the unlikely event you haven’t been following the story closely.

If you have a security clearance or are in line for one, you probably shouldn’t click on the link, because it contains copies of pages from the leaked NSA catalog:

I See What You Did There – NSA Hardware Guide

2014-01-09
Santa Ride: Crash Report

While walking from the Metropolitan Museum of Art to Grand Central on a frigid post-Christmas December evening, we encountered this storefront display:

Santa Ride – car

A closer look at the monitor in the background:

Santa Ride – crash report

Hmmm. Bit of a surprise: not a Windows box.

After walking two miles along Madison Avenue, I didn’t see one single item in the store windows that I’d buy, even in the after-Christmas discount season. Mary wasn’t enthralled by a pair of diamond-encrusted emerald earrings the size of my thumbs, either, which is likely a Good Thing.

We stopped in the Ugg Boot Store, both to warm up and so I’d know what all the spammers have been hawking…

2014-01-07
Kenmore Dishwasher Sound Deadening Sheets: Slip Sliding Away, Redux

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:

Dishwasher sound deadener – wrinkled asphalt sheet

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…

2014-01-04
Planetary Gear Bearing: Now With Knurling!
OK, I couldn’t resist. Tweaking a few lines of code wrapped a knurl around emmitt’s Gear Bearing for enhanced griptivity:

Knurled vs original Planetary Gear Bearing

That image has desaturated red to suppress the camera’s red burnout. It looks better in the realm of pure math:

Planetary Gear Bearing – Kurled – solid model

Reducing the tolerance parameter to 0.4 produced a surprisingly rigid, yet freely turning, bearing that required no cleanup: it popped off the plate ready to roll!

The heavy lifting in the OpenSCAD source code remains emmitt’s work. I replaced the outer cylinder with a knurl and simplified his monogram to stand out better amid the diamonds. This is the affected section:
```
... snippage ...
translate([0,0,T/2]){
	difference(){
//		cylinder(r=D/2,h=T,center=true,$fn=100);
		render(convexity=10)
		translate([0,0,-T/2])
			knurl(k_cyl_hg=T,
			k_cyl_od=D,
			knurl_wd=5.0,
			knurl_hg=5.0,
			knurl_dp=0.5,
			e_smooth=5.0/2);
		herringbone(nr,pitch,P,DR,-tol,helix_angle,T+0.2);
//		difference(){
			translate([0,-(D/2+4.5),0])rotate([90,0,0])monogram(h=10);
//			cylinder(r=D/2-0.25,h=T+2,center=true,$fn=100);
//		}
	}
	rotate([0,0,(np+1)*180/ns+phi*(ns+np)*2/ns])
	difference(){
		mirror([0,1,0])
			herringbone(ns,pitch,P,DR,tol,helix_angle,T);
		cylinder(r=w/sqrt(3),h=T+1,center=true,$fn=6);
	}
	for(i=[1:m])rotate([0,0,i*360/m+phi])translate([pitchD/2*(ns+np)/nr,0,0])
		rotate([0,0,i*ns/m*360/np-phi*(ns+np)/np-phi])
			render(convexity=10)
			herringbone(np,pitch,P,DR,tol,helix_angle,T);
}
```
I also added a few render(convexity=n) operations to improve the preview, but that’s just cosmetic.
2014-01-03
Emergency Eye Wash Station: Watch Out!

Spotted this in a greenhouse:

Cluttered emergency eye wash station

Just like fire extinguishers and bike helmets, you never know when you’ll need to use this thing in a hurry… then it’s too late to clean out all the crap that accumulates on any flat (or concave) spot.

Not that I’m completely innocent, of course.

The DSC-H5 had been outdoors for a few hours, hiking with us at 25 °F, so the lens fogged instantly when we walked through the greenhouse door.

2013-12-28