One of the challenges one finds when deciding to plunge down the "rabbit hole" of tagging is the lack of color images available to aid in identification and learning. Resources that are out but not readily or freely accessible have low res. black & white images or sketches. This is especially true when you wander into the forest of tagging freaks/oddities. As an area of deep interest to me I thought others might benefit having color images to reference if they want to pursue tagging luminescent varieties. Since transportation coils are very popular I thought I would start with some of the luminescent freaks/varieties the can be found. Some of description I am using were described by Gene Paquette in a paper written by him on luminescents plus other sources and my own observations. Some of the images are a little fuzzy and sizing varies but you'll get the idea.
Vertical and/or Horizontal Gaps These are horizontal and/or vertical tagging gaps caused by use of four shell-type rubber plates. Vertical gaps are complete while horizontal gaps may or may not be complete.
RR Tracks Appears typically as two parallel tagging gaps or "hot" lines resembling railroad tracks running horizontally on some Cottrel press coils. Position of the gaps varies as shown. Caused by be reuse of the same rubber ink transfer roller used to print the raised lines on precancel plates.
Untagged Top or Bottoms An untagged uneven band that extend horizontally across either top or bottom of coils. Rubber roller used to apply tagging covered all but a small portion of the paper web margin which is usually cut off. Unevenness speculated to be caused by drifting of the paper web and wear on edge of roller.
Screw Gaps Visually appears as a bulging or rounded gap typically aligned with a tagging gap. It results from the holes where screws were inserted through the rubber tagging plates to attach them.
Mat heavily worn so horiz. gap and screw gap not as distinct.
"T" Clip Gaps "T" clips were also used to attach the rubber tagging mats to printing cylinder. This leaves an untagged "T" shape appearing as sharp or roughly shaped "T" at bottom or top.
Misregistered Block Tag Found on many block tagged issues. Visually the block tag can be shifted in any direction. Shifts can be extreme enough that the gap normally occurring over perfs occurs through the center of the stamp.
Wrinkled or Rippled Appears as wrinkles, ripples or what look like lightning bolts in the tagging. Caused by worn surface of rubber tagging roller from printing pressure and age. Wrinkles, ripples or lightning bolts appear as brighter artifacts within the tagging.
Wrinkled and normal tagging for comparison.
Spotty or Marbled Tagging looks like a series of spots or like a marbled stone surface. Typically uneven and often appears as having gradient effect from light to heavy tagging. Looks like the Omnibus is in a snowstorm below.
Variations in the amount of tagging effecting brightness.
Random vertical tagging gaps.
Examples of variations within a stamp; normal plus RR tracks and wrinkles.
It would be very useful to have a resource that had color photos of what each type tagging was for a particular issue and its usual appearance along with varieties and errors or peculiarities. There is great confusion on the part of collectors concerning this area of philately.
Vey well done Mstocky2. Wished you could do a write-up for Coil Line, the journal of PNC3. I did find a small problem though. In my own collection I have a different explanation for a tagging hot line. It is not the same as a "railroad track" but a very bright line or streak of taggant usually next to an area that is un-tagged. For info please see Ron Archer's "Reseach report" in Coil Line, May 2009, page 77 ( Available at our website www.PNC3.org ). Also, anybody interested in the article by Gene Paquette - it is offered by the United States Stamp Society as a reprint ( no 4 )
Mstocky2, a couple more items that may be of interest. The strip of 5 of the Motorcycle coil that you show is known as the "Mountain tagging" or the "Rollercoaster tagging" variety. It has been known for as long as the stamp has been available, but I strongly believe it occurs on other values as well. Also maybe of interest, the tagging breaks that you show are like precancel gaps and are collected as such. Tagging gaps occur on four Cottrell Press Transportation Coil: 2 cent, 5 cent, 5.2 cent and 17 cent as well as several B-Press items. I even collect tagging breaks on the Transportation Coils that are block tagged
I have been traveling a lot for work lately but with angore's encouragement I wanted to start getting some of this information out there even if though the pictures were somewhat inconsistent in quality to start.
Petert4522 - In Gene P.'s paper he referred to what I called "Railroad Track" tagging as "Track Tagging Lines" (see below) and describes it as resembling railroad tracks. I have also seen and heard elsewhere it called Railroad Track tagging so I used that term. He also indicated it could be found in a gap version or "hot" line version. I have never seen or found a "hot" line version of this type and it was a bit of a surprise when I read the paper. I have seen "hot" and have "hot" line versions of tagging which I agree are different and see where this could be confusing. Thanks for pointing this out.
I have had a strip of three of the motorcycle with the "Mountain" tagging for some time but recently found a nice strip of 18, a partial view of which I posted here. I was going to label it "Mountain Cruising" because I didn't know it had a reference name. The Omnibus and Firepumper appear to be of this same type which is why I included them.
Didn't know that block tagged versions could have a tagging gap so now I have another type to hunt for. What does this look like?
Don - I responded to your email expressing interest.