Hey Charlie, Ray of Sweetwater Knives ( Paladin ) is the Best Authority I know of on this subject and if you do a search in this forum there's a good chance the info is closer than you think. It gets Tricky from what I understand. Lots of overlapping and changing back and forth through the years. To save Ray a lot of typing I have an excerpt from him explaining it in another forum but I'll cut and paste it just to make sure it is here on AAPK. If he has any new info to add or can clarify anything I'm sure he'll be around before too long.
I hope this is alright with everyone
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Ray says ~~ It is very frustrating trying to date Eye Brands. Neither Goins nor Levine is any help.
The only accurate info I have found is an article authored by Joe Dobbs and it appeared in Knife World in August, 1983 and again in the Best of Knife World, 1993. It obviously does nothing on the newer Eyes but it does have good info on the older ones.
It kinda boils down to a combination of stamps and shields.
The straight line stamp is the oldest and most desirable. It was used up through 1965, though not exclusively. It shared time with the logo stamp with C. SCHLIEPER around the curved upper part of the Eye logo and this one was used into the early 1970s.
Then, in the mid to late 1970s until 1981 they used the Eye Logo (over) GERMANY. There is a gap there I cannot explain.
In 1981, they returned to the C. SCHLIEPER (over) the Eye Logo.
As to the shields, the earliest was a plain badge-type or federal. I have to admit, I am not sure of the difference in the two, if there is any.
In the early 1970s, they went to the logo (over) SOLINGEN. Clarence Risner told me that the round shield came into use in the late 1980s. I emailed James Marek, a jobber for the Cruse family who controlled all Eye Brand distribution at the time with this same question. The reply follows: From James Marek, a jobber for Cruse during the early days who keeps records on everything: The round shield was first introduced in November, 1983 on the #815 pattern (4 1/4", large spear, gut hook, saw and corkscrew on back). All stag patterns began having the round shield in January, 1984, except Baby Lima DSL. Glad to help.
What this all goes to show is that aging Eye Brands is a perilous or maybe tricky proposition. These all overlap to accomodate existing supplies and it is not a specific process.
I did not intend to get so wound up but it's hard to get it out in a few words.
Ray
One thing I failed to mention is that pattern numbers on the tang stamps first appeared in 1979.
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Ray is a great fella and I sure hope I'm not doing the wrong thing or in the wrong way…
reddirtater