T206 "printer's mark" and sheet layouts

[Leon]

Love all of the crop marks on the cards!!

[KingFisk]

I got a Johnny Evers (blue sky) in the mail today and noticed what I think is a crop mark on the back in the upper left corner. Dumb question and possibly answered elsewhere but I found another thread indicating these marks should have been erased. What was process for erasure? I ask because the mark on my card looks to be the same red as the Sweet Cap red printing. Would have just been a matter of using an eraser to remove that section of ink? Would that otherwise affect the card's surface (I.e., flake off some of the card stock)?

[steve B]

Depending on the exact purpose, the marks could have been erased from the plate/stone. Since the stone is limestone, and the parts that are intended to print are on the stone with an oily substance, erasing is pretty easy. The press operator just "erases" it with a limestone stick.

Most of these marks were probably intended to be left on. It's likely they were intended as marks showing where the edges of the sheet should be trimmed off. Of course, in practice the sheets were cut face up, so the marks were useless.

Ones like on the Elberfeld above may have been intended to be erased. They're more like layout marks than indicators where to cut.
The ones that were commonly erased were the layout marks that were at the center of the design edges on the front that were there to make sure each color was laid out properly aligned.

Steve B

[Pat R]

Here's another Demmitt with a large crop mark and the same flaw in the
top of the frame line as the one in post #12.
Demmitt Crop.jpg

[KingFisk]

Originally Posted by steve B

Depending on the exact purpose, the marks could have been erased from the plate/stone. Since the stone is limestone, and the parts that are intended to print are on the stone with an oily substance, erasing is pretty easy. The press operator just "erases" it with a limestone stick.

Most of these marks were probably intended to be left on. It's likely they were intended as marks showing where the edges of the sheet should be trimmed off. Of course, in practice the sheets were cut face up, so the marks were useless.

Ones like on the Elberfeld above may have been intended to be erased. They're more like layout marks than indicators where to cut.
The ones that were commonly erased were the layout marks that were at the center of the design edges on the front that were there to make sure each color was laid out properly aligned.

Steve B

I totally missed this response to my question last month. Thank you for the info!