What is it? Set 274

[Rob H.]

This week I need some help with number 1559:

[Charles Lessig]

Tin roof seam clincher

[Kevin(Bluey)]

1557 is a black and white TV testpattern used to set the black ,white and grey tones . 1560 is a machinists" jack used to adjut the level on workpieces on a machine table .The Vee is used for round bar work pieces.

[Alexander Thesoso]

1555 I dunno why it was cut as shown... but I do question that the picture is of one bolt. I would question how you could cut one bolt to make the two pieces shown. The left piece seens to have the cuts on the chamfered end. I can imagine how to make the two pieces from two bolts with a saw. I suppose there might be some situation where the two pieces, together, might make a hard-to-remove setscrew.

1557 Indian Head Test Pattern

of long-winded discussion in lots of places about how to figure out what is wrong with your part of a television system and how to blame it on someone else.

[Alexander Thesoso]

OK... So my comment about needing 2 bolts is stupid. Of course, you could make it from one long bolt. Just cut it off and turn the left piece around. I should have thought harder before writing.

[grrly girl]

Finally, something I recognize. TV test pattern. Grrly Girl

[riverman]

More than that: a TV CAMERA test pattern. It was to focus and align the electronics on old TV cameras in the studios. I worked in TV while in college, and we'd focus our RCA cameras on the "bars and tone" chart so the engineers could align the signal from the camera. The test pattern was broadcast to the general public over the airwaves so that they could also align the signal being sent out, but most folks at home who go the test pattern (usually for 15 minutes before the station went 'on air') probably thought the pattern was meant for them. TV sets were self-adjusting well before this test pattern fell out of use.

--riverman

[riverman]

1555: My guess is that its a type of lock-bolt. You start the lower part into a threaded hole, then finish by twisting the top part down into the hole, driving the lower part through until the top is flush. When someone tries to back the top half out, the top section turns 60degrees, putting the top half threads and the bottom half threads out of align, jamming the entire works in the threaded hole. 1558: No idea why, but something to do with cranberry raking comes to mind... 1559: Obviously some sort of crimper?

--riverman

[J. Clarke]

Just an aside but the page says "from the 1930s". While it was created in

1939 it was used into the '60s or early '70s (I wasn't keeping notes on such things so don't recall exactly when I saw my last one).

There's an interesting wikipedia article on it.

The guy who owns the original artwork has a page on it at and you can link from there to his page on the monoscope test camera of which it was a part..

[beecrofter]

559 looks like a crimper to do standing seams on copper roof or terne plate

Don't quite know about the lute, could be for asphalt, Japanese garden gravel, or getting the horse apples out of the show ring.

[Rob H.]

Thanks, I think this is probably correct for number 1559 though I couldn't find one like it on the web, the owner of it had guessed along the same line but he wasn't sure.

Rob

[Carl G.]

This type of trick bolt is sold in novelty shops as a puzzle or magic trick. When assembled, a nut covers the split in the bolt. The bolt is usually inserted through a small ring and the nut used to lock the ring onto the bolt. The puzzle is to remove the ring. The nut can only be removed by holding the bolt in an unorthodox fashion (e.g, holding it tightly by the ends between thumb and forefinger). If the bolt is held in the regular manner, the nut locks in the manner you described.

Carl G.

[Andrew Erickson]

1555 - Perhaps these formed some sort of a poor-man's mechanical interlock or latch mechanism, with a non-pictured base with tapped holes at various orientations. (They could also be used as a valve of some sort, but I don't think they'd work too efficiently to be worth the effort.) 1556 - Umm, clamp-on spurs for part-time cowboys? 1557 - Ye famous olde "Indian Head" television test pattern, used to adjust geometry, contrast, brightness, and measure (to some degree) distortion and resolution. Still used well after the 1930's, I believe. 1558 - Rake (I assume for leaves or hay); the hinged comb I think is designed to allow one to clear out the tines by pushing the rake forward a bit after one or more pull strokes. 1559 - Seems to be a sheet metal crimper/bending brake, maybe for forming/sealing the seams on metal roofing or flashing. 1560 - Adjustable mount for a tube, with fairly precise height adjustment; I'd guess perhaps for use in aligning optical instruments along the lines of rifle scopes.

Now to read the other guesses.

[Tom Veatch]

Yep, I remember seeing that test pattern when Channels 3 and 12 in Shreveport, La. signed off in the late '50s.

Tom Veatch Wichita, KS USA

[Wild_Bill]

I believe this is the correct description for the parts shown as #1555, Carl.

The part not shown is the nut. The set that I have includes a nut that is about 3 times longer than a common size nut (and the overall bolt size is longer).

The nut will screw onto the parts of the "bolt" effortlessly, and the assembled parts look like a bolt and nut.

But when the nut is reversed to unsrew it from the "bolt", the end section of the bolt locks the nut by a cam action of the machined lugs(?), and the nut will not unscrew.

The person that knows it's trick bolt/puzzle can hold the hex (with the little finger against the palm), and turn the end section of the bolt clockwise holding it with the thumb and index finger (looking at the end of the bolt), which prevents the cam action from locking the nut, so the nut unscrews with no effort.

[Rob H.]

This is correct, although mine can't be solved by holding it tightly by the ends between thumb and forefinger, the link that I'm planning to use on the answer page also recommends this same solution but for some reason this doesn't work for me. The only way to solve mine is to hold it by the small end and then turn the nut with the other hand, or hold the nut and turn the small end, as also suggested by Wild Bill.

Rob

[Barbara Bailey]

"Rob H." wrote in news: [e-mail]: