Example Stamp - Scott O252f - Detailed Analysis

There is lots to analyze when it comes to stamps..There is more than the eye can see..Take for instance this Scott O252F (O.H.M.S.) stamp.

A lot of O.H.M.S. stamps are as most people don't realize, have 2 different size perfins..Below is a used pair of Scott O252F stamps.


At first glance they look normal, but as you can see looking at the picture below there are not the same.


I have blown up the perfins to take a measure..BTW, the words "UOM" (UNIT OF MEASUREMENT)is a local printing term we used in printing class, because back then there was NO metric and we used any measurable device we could to get a measurement for transferring dimensions from one plate to the next...So as we can see the UOM in the picture below is used to give me a percentage difference.

That is a distinguishable difference most people miss...There must have been at least 2 different perfin wheels for this stamp.

Also perfin damage is apparent as the stamp run goes on as shown by the picture below.


Now here is the kicker, colour differences as shown below.

Now most collectors judge colour differences do to oxidation..This may be true, but not in all cases...When printers mixed colour (as I did many, many times as a lithographer)..Most people will be amazed at how me and a lot of printers mixed ink for colours.



One reason there are colour differences on old school colour mixing is when they mixed a colour and did a run, went home to do another run the next day, I and other printers cleaned the rollers and ink reserver for next day printing...It was 100% impossible to hand mix the exact same colour 2 days in a row..Below is a picture how ink was mixed..


Yes oxidization plays havoc on stamps, but colour mixture play more part in colour differences. With these stamps above, the more rose added the more the colour change.I had a couple of anonymous collectors contacted me to get my experience with colour differences explained to them, thought I would pass it on to other

Yes, storing stamps in sun light affects colour, towns in which they were stored, example, if the stamps were stored in a post office, say near Stelco in Hamilton (heavy steel making company), with heavy industry (in the air) can affect colour...Earlier stamps at the beginning of 20th century were stored, they were (could have been) covered to protect them, and they could have even used burlap bag covers that can chemically affect colours.

Any questions, opinions would be accepted with a smile.

Robert

Nice article Robert.

There are a number of shades that resulted from multiple printings of the same design where the inks just don't match. This is especially true for the King George VI stamps of the British Colonies because of the long production runs (10 - 15 years for some sets), but also for the effects of World War II on the production facilities and supplies.

I was not aware that two different sized holes are seen on this set. I will have to keep an eye open for them.

Robert, there were two machines made for the 4-hole OHMS perforations. Each machine has ten (10) dies that allowed (up to ) 10 stamps to receive the OHMS perforation at a single stroke. It was possible to do more by stacking the sheets but it is unlikely that more than 3 sheets would be perforated ot one strole because of the pressure required to drive the pins through three thicknesses of paper.

The 5-hole OHMS had only one machine that was made with 5 perforating dies only.

In both cases, the machine was manually activated.

The following illustration and text is taken from a booklet produced in 1966 by Roy Wrigley

Thanks for the additional information Garfield.
.


Question..My understanding the perfs machines had a concave base that would allow complete penetration of the stamps...Correct me if I am wrong.

I measured the perfs center hole to center hole as shown below, or am I just over analyzing..?


Robert