Guide Lines And Joint Lines For Coil Pairs

I was looking at my Liberty series coil set. I have pairs for all of them, but I also seem to have line pairs. Does anyone have any pictures showing the difference between a guide line and a joint line?

Some of my pairs have 2 well defined parallel lines along the perfs. One pair has one thick solid line, not as well defined as the others. (I need to take the photos yet). But just from this description, does anyone have any input? Thanks.

Steve

Hi Steve, and welcome to the forum. We can most likely help you, but we will need pictures to show us what you are talking about.
I do not believe guide lines occur on coils, but then again I have been wrong before!


Peter

Thanks Peter, let me those pictures posted.

A guide line is an intentional line added to the plate, a joint line is from offset printing and is an unintentional line caused by ink collecting in a joint. I used to think it was a joint between 2 offset plates, but someone suggested to me that it might be a joint in the offset blanket (although I'm not convinced of that). The joint lines don't always ink uniformly, and also with a multicolor offset issue you can get multicolor joint lines.

Guide lines are from flat plates.
Joint lines are from rotary plates.

Alright everybody, it's only fair that I post my pictures if I am asking for pictures as an explanation for what I have.

This is the Liberty coil series. I am quickly finding the Liberty series to be very intriguing for a modern series.

The Washington and Jefferson coil pairs have 2 clear parallel lines in the perf area. The Lincoln has these lines also, but the space between them is filled with ink, making one thick line. Any comments?

Thanks again for all the replies.

Steve

In my opinion all three are joint lines. Depending on how much ink deposits in the space between the plates, joint lines will always be different looking. Joint lines are also called seam lines by printers.

Peter

Thanks, Peter, I was thinking the same thing. This is the first time I've noticed these lines. Stamp collecting has gotten me to pay attention to detail!

For Stickney rotary press coils, these joint lines occurred between every 10th and 11th stamp from the other closest lines in a roll. These joint lines marked where ink got deposited between two pairs of curved printing plates.

Thanks jogil. It seems like the joint line stamps will always be more scarce than simple pairs just because of the spacing. Scott catalogue gives a significant premium to these as opposed to normal pairs.

Not only are they more scarce, there's a whole bunch of collectors that specialize in them.
As an example. On the newer ( after 1981 ) plate number coils the prices are always for plate strips of 5 ( PS5 ) or longer whereas strips without the plate number go for little more than face, if that much.


Peter

Thanks for the insight Peter. Yes, there's always a group of collectors for some specialization. I have found that the deeper one goes into a specialization, the amount of knowledge and enjoyment increases for the hobby.
Ultimately, I think many collectors simply have a passion for something and enjoy getting deeper into it. I only collect things I enjoy. Many times, I get the same enjoyment out of a stamp with low catalogue value and a stamp with high catalogue value. Of course, once you get to the very expensive stamps, there is also a pride of ownership in a valuable item.