2 Attachment(s)
Finale to the lamp shade caper
The photo slide drilling/punching jig previously described is intended to mount on good neighbor Janna's HF bench-mount drill press, which has the customary table with a center hole and four slots. The jig will be mounted so the 1mm hole is over the hole in the table. I've added two studs threaded 5/16 x 24 to the jig to engage the slots in the drill press table. I made the studs on the lathe with lathe-cut threads and one end turned to 0.250 (or so) to enage holes in the jig that were drilled and reamed to 0.2495. The length of the turned part is about ten thou shy of .125, the thickness of the plate.
I'd screwed up the diameter on the turned parts so it was a sloppy fit (not a press fit) on both of them. Good thing I reamed the holes accurately, right? Oh well! Now how to recover?
There were good square surfaces between short stubs and threaded bodies even if I blew the diameters, so I stuck the studs in the holes, clamped them tight with Kant-Twist clamps, and gave them a very brief TIG kiss on the threaded sides just enough to stick them in place with welds the size of a pinhead. Then I turned it over and did rosette welds on the other side that later disappeared with 10 seconds of grinding. Unlike some studs those of us with daughters might have known, these studs are there to stay. No heat distortion on the plate because I was in and out of there like a surgeon with a golf date.
Attachment 49523
All that was left to do was nuts and washers. I din't have no 5/16 x 24 nuts in my hardware collection, or at least none I could find easily in the not-easily-reached bin of misc 5/16" bolts. (It was easily reached 25 years ago when I put it there)
I figured that I could make nuts in less time than it would take me to drive to the nearest hardware store to buy them (and back), so that's what I did. I found some 1/2" AF (across flats) hex stock in one of my rawstock racks. It was brown so might have been brass, or bronze, or copper. It's been in that rack for at least 20 years and it came from someone else's rawstock rack back then.
It immediately became quite clear when I started to machine it that it was brass. YAY! I made two nuts in just a few minutes. Then I thought they'll need sturdy washers under them and I had a little fist-length drop of 1" dia brass on the drop rack by the lathe, so I made two washers .090" or so thick.
The brass washers were pretty as machined. The nuts were still brown on the un-machined surfaces. Janna makes jewelry. Hm! I decided to polish the nuts. Only took a coupla minutes at the buffer and neither of them escaped into the fourth dimension hole behind the buffer that has glommed so many parts never to be seen again.
Attachment 49524