Andy, 
Yes - This was covered at a SPNHC talk in 2014. 
You can find the program here:

http://www.museumwales.ac.uk/spnhc2014/programme/

And here is the synopsis:

The value of examining pins as part of assessing old insect collections

E. Geoffrey Hancock
The Hunterian (Zoology Museum), University of Glasgow,
Glasgow, G12 8QQ, UK
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There are a number of instances in which the physical
characters of the pins in insects have been instrumental in
confirming their status. This might be in placing them between
certain date periods, as originating from one particular
collecting event or confirming their place within a type series.
Recent research on William Hunter’s (1718-1783) insect
collection has added considerably to knowledge of early
pinning practice. Provenanced insect collections from that
time are rare. Before mass-production techniques became
available pins were made using a series of labour intensive
processes. Pins were relatively expensive items until the 1830swhen machinery was developed for mass production. No
pins were made specifically for entomological use at the time
Hunter’s museum was being created.
Many insect collections of the time have not survived intact.
William Hunter’s private museum in London became the first
Hunterian Museum, built in 1807 in Glasgow, specifically to
accommodate his bequest to his alma mater. What is now
the oldest public museum in Scotland was thereby created.
The insect cabinets were part of this and retain their original
arrangements; the specimens were named by J.C. Fabricius
(1745-1808), engaged by Hunter as his zoological curator.
Therefore it provides an important documented resource for
historical entomological investigations. Detailed morphological
pin descriptions and metallurgical analysis have now been
conducted. Developing collections management technology
for insects in the eighteenth and early nineteenth century,
in which the role of pins was crucial, allowed entomology to
progress as a descriptive science.


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Christy Bills
Invertebrate Collections Manager
Natural History Museum of Utah
301 Wakara Way
Salt Lake City, Utah 84108
________________________________________
From: Entomological Collections Network Listserve [[log in to unmask]] on behalf of Andy Boring [[log in to unmask]]
Sent: Monday, November 30, 2015 3:57 PM
To: [log in to unmask]
Subject: The history of insect pins

Hello Everyone!

I was curious if someone could direct me to information about the
history of insect pins.  I'm curious about when they first became
manufactured specifically for Entomologists, who might have been the
manufacturer, and the initial costs.

In short, I'm recurrating a series of specimens that were collected in
the USA, in the 1930's.  These were collected during the great
depression, and it seems like there was some improvisation in the pins
that were used.  I'm curious about where these fit in the scheme of
financial difficulties, available manufacturing, and who might have
redirected their manufacturing to fill the niche.

All the best!
Andy