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?

Minilathe MT3 Spindle Collet Fitting

I’ve used the LMS set of inch-size MT3 spindle collets on occasion, but releasing them required an unseemly amount of drawbar battering. It recently occurred to me to check their fit in the spindle taper:

Minilathe – MT3 collet – taper test

Huh.

The only place they touch the spindle is right around the base, so it’s no wonder they clamp poorly and release grudgingly. I tried several others with the same result.

Cross-checking shows a much closer fit along the entire length of the dead center, so it’s not the spindle’s fault:

Minilathe – Dead Center – MT3 taper check

Stipulated: we’re not talking toolroom precision here

I set the collets on centers:

Minilathe – MT3 collet – drive setup

And proceeded to file away the offending section to move the clamping force closer to the business end of the collet:

Minilathe – MT3 collet – filed result

I did the small collets, the ones I’m most likely to need, and left the big ones for another rainy day.

They don’t have much clamping range and seem good only for exact-inch-size rods.

I should lay in a stock of ER16 and maybe ER32 collets for small stuff.

2019-01-16
Lamp Posts vs. Reality

Spotted this in a mall built just before the 2008 financial implosion:

Round Lamp Post in Square Pavement Hole

Maybe the original catalog items went obsolete by the time they signed up enough tenants in that section to justify any lighting at all?

In related news, a facelift some years ago at the motel next to the decaying Red Oaks Mill dam installed square lamp posts on the existing square concrete pedestals, but replaced the original metal conduit with a plastic sheath:

Square Lamp Post with Cut Cable Shield

The cable may sit low enough in the recess to survive, but I wouldn’t bet my life on it.

2019-01-13
Just A Typo. It Could Happen To Anyone: Capacitor Edition

A bag of 100 nF ceramic caps arrived from across the continent (“US Stock”) and failed incoming inspection:

Mislabeled 100 nF ceramic capacitor – actual 50 nF

The capacitor mark says 104, which is what you’d expect on a 100 nF cap, but the first half-dozen out of the bag measured around 55 nF, far outside even the loosest -20%/+50% tolerance.

Stipulated: the factory can ship every capacitor it makes with a proper mark.

Given their (lack of) provenance, they could be mis-marked 47 nF caps.

Somewhat to my surprise, a refund occurred instantly after I reported the problem.

Trust, but verify.

2019-01-11
Stink Bug Haven

We hung a pine-cone wreath beside the back door (a.k.a. the only door we use), replacing a Welcome sign painted on a slate tile. Of course, the tile had long provided a sheltered spot against the house siding:

Marmorated Stink Bugs and Spiders

Reports from the garden suggest Brown Marmorated Stink Bugs aren’t as damaging as they once were, perhaps because something has developed a taste for them.

We hope whatever it might be eats well this year.

2019-01-06
Cable Ports vs. Foot Traffic

Spotted this under a counter at Panera Bread:

Power and network cables – floor plates

You’re looking downward from the edge of the communal meal countertop at the power and network cable ports in the floor. The cables snake into the counter legs and emerge at the countertop to provide AC power, USB charging, and wired network ports in addition to ubiquitous WiFi: all the conveniences of modern dining.

Alas, down at floor level, the poor cables get kicked against the edge of their cover plates, bent with no strain relief, and seem jammed under the sharp edges of the leg extrusions. I expect the connectors below the hatches also endure a nightly bath of gritty water, with bonus salt during the winter months.

And, yes, the AC power plug sits halfway out of its socket, with the blades exposed.

2019-01-05
Darlington Transistor Sorting

A discussion of random numbers at Squidwrench brought those gamma ray detectors to the top of the heap, with the observation I probably needed a few more Darlington transistors:

Darlington transistor – hFE sorting

Sorting two lots of 50 transistors by gain kept me out of trouble for a while:

Darlington transistors – sorted

Those are MPSA14 NPN and MPSA64 PNP transistors, with DC gains ranging from around the spec’s minimum 10 k spec all the way up to well over 100 k.

2019-01-03
Blog Summary: 2018

Page views for 2018:

Blog Post Summary – 2018-12-24

At this late date, the RepRap site has a much better G-Code reference, at least for the weird and wonderful assortment of 3D printer commands.

Given that I’m at best a secondary reference for Toyota Sienna ABS trouble codes, things must be getting grim out there in the minivan crowd.

And, as always, houses (and especially plumbing) are trouble!

As for everything else, well, it’s just me and my shop notes …

WordPress reports 101 k ad impressions per month for 24.6 k “page views”, suggesting most folks see four ads per page. If you’re not using an ad blocker, start now!

Those seem to be the most aggressive (and thus highly desirable to advertisers) video ads, because WordPress pays me a whopping 8¢ per kilo-impression; a few percent of the Youtube rate. The numbers are dropping, though, suggesting ads will never push me into the ranks of the thousandaires.

Now you know.

2019-01-01