T206 Printing another small bit of proof.

[steve B]

Back in August we discussed a card Chris had found with a recurring major printing flaw. Starting at post 238.

http://www.net54baseball.com/showthr...118253&page=24

I couldn't figure out how the mark and embossing happened because at the time I was convinced the printing had been done on an offset press.

In an offset press, the stone or plate prints to a rubber roller that then prints the paper pressing on a steel impression cylinder. I didn't see a bit of debris getting stuck to the impression cylinder. without it doing far more damage than the impression on the card. And it also couldn't have been stuck in the offset blanket since the impression was on the back.
An that was where I got stuck and sort of left it as something to think about later.

Yesterday it all came together. I had gotten the card from Chris (Thanks Chris!) and was looking at it fresh, and in hand it was just as puzzling. I'd also been discussing printing in general with Bryan and found a few videos of flatbed presses in operation. I wanted a video of an old offset press and went looking. I didn't find one of a press old enough, but did find a description of the invention of the offset press for paper.

That didn't happen till 1903-4, although offset presses were used for printing onto tin starting around 1875.

The key was this (red lettering mine for emphasis)
"In 1903 and 1904 Rubel experimented at the Nutley facility with photo reproductions transferred onto lithographic stone through a screen. Although the testing did not yield significant results, Rubel’s work on a stop cylinder press led inadvertently to an important breakthrough. When his assistant miss fed a sheet and the rubber impression roller came into contact with the lithographic stone, the reversed image was transferred this roller. When the next sheet was fed, it had an image on both sides: one that was product of the direct contact with the stone image carrier as intended and the other with a wrong-reading image from the “indirect” rubber roller.

Once the “indirect” image was found to be superior in quality to the direct one, Rubel and his collaborators expanded their testing along these lines and perfected the technique. This included a complete redesign of the press based upon the offset principle."

From this page which is the best I've found so far on Washington Rubel
https://multimediaman.wordpress.com/...bel-1860-1908/

And there it was. I hadn't realized the impression roller of a stop bed press was rubber. What caused the misprint was a nail or other bit of debris getting into the press, damaging the plate and becoming stuck in the rubber impression cylinder. Every card after that would get the blue hockey stick mark and the impression of the debris. (I'm almost positive it's a nail. )

And that's as close to solid proof as to the sort of press used as we're likely to get. That particular misprint can happen on a flatbed press, but not on an offset press.

As a bonus - The detailed back ghosts are impression cylinder offsets. And I'd been wondering how they were that nice from a steel impression cylinder. When they're actually from the rubber impression cylinder and similar to the error that led to offset presses for paper.

And that's pretty darn cool.

Rubels press was sold to a place in san Francisco and arrived in that area just after the earthquake. Spent a year or more in storage in Oakland, was eventually used for a time and found its way eventually into the Smithsonian.

I can't rule out other presses, offset, and possibly multiple color, but I can say for sure that at least some of the P350s were done on a flatbed press. And if P350 was run flatbed I don't see the smaller runs being done some other way.

Steve B