When I purchased the PG5 in the middle it was listed as “vintage” so who knows how old it really is.
The one on the bottom was purchased on Amazon a few years ago.
At some point it appears that the PG5 went from having no labeling (like the Graph II) to having labeling. (I’m glad to see that the script matches the other PG models.)
How can we date our PG5s? Do we know if we can at least narrow it down to year ranges using these labeling differences?
Is anyone aware of any documented differences to the internal workings of the PG5 over the last 50 years?
Thanks
Edit: I was avoiding it, but temptation got the best of me and I finally took my “vintage” PG5 apart.
The lead tube does have a date code of 770225, so it is “vintage”, but does anyone know when they started putting text on the PG5 barrel?
I wonder whether these many variants were really intentional, i. e. whether they were the result of deliberate changes to the material and design over the years or whether they came about more or less by chance through combination or batch variations (e. g. in the plastic of the yellow ring). An older document on mechanical pencils in Japan states that many of them were made at home; I would not be surprised if this also led to unplanned variations. And then there are the sellers who combine parts from different pencils without pointing this out …
There are many reasons. Like you said, sellers could mix parts from different pencils. I spent a lot of money and time to keep buying tons of random samples just to figure out the timeline and to avoid being mislead by the “mix” problem.
Many of these pencils were made at home, but not likely Pentel did this. They did have a factory from the very beginning. The PG series is a long lifespan product line, modification can be applied at any point during this period for any reason. Modification here includes not only the change of structure/material/sticker, but also the machines and all the parameters related. Modifications can also be applied forced by a higher level change, For example, the name change of the company in early 70s.
The earliest Graph II’s I have do not have the threaded white plastic sleeve. Instead, the body of the pencil has an integrated tube and the lead indicator is a small aluminum ring that slides off. The lead reservoir and clutch assembly screws into the grip, like the earliest Pentel 11’s did. The cleaning wire is completely straight; no friction bend.
At best I’ve been able to tell, the only visible external difference between threaded barrel and non-threaded ones is that the barrel is just a tiny hair larger in diameter than the nose cone on the former, whereas the joint is more seamless on the newer ones.
The font used in the lead grades is ever so slightly different between the aluminum ring and the adhesive label on the later generations.
If the pencil is boxed, look for the Pentel logo on the lead refill tub and then instruction sheet. If it’s the old block logo, it will be the older version.
By the way I have a couple of brand new PG5s and they have mold codes of 11 and 15, suggesting that either they are a new series of molds because of some minor design change (and it isn’t just the Pentel logo, because the 1977 pencil used the current font), or that the numbers have been recycled for some other purpose, maybe to denote factory location?
The 2-digit date code is stamped on the lead reservoir for these.
