Has Anyone Seen "Fins" on an Insulator

Welcome to our Antique Bottle community

Be a part of something great, join today!

geofrac

Member
Joined
Jun 14, 2019
Messages
15
Reaction score
7
Points
2
Hello:
I picked this up at an antique store in California. It looks like a normal insulator, but it has four small "fins" below the lower lip. There are four 90 degrees apart.
It has no markings on it.
My questions are:
1. What are the "fins" for?
2. Is this a rare insulator?
3. How old is it?

Much Thanks,
Greg Stanley - California
Pic 1 (2).jpg
USA
 

Attachments

  • Pic 2.jpg
    Pic 2.jpg
    285.8 KB · Views: 81
  • Pic 3.jpg
    Pic 3.jpg
    284.9 KB · Views: 88

nhpharm

Well-Known Member
Joined
Apr 24, 2007
Messages
2,978
Reaction score
1,655
Points
113
That is a CD 106.3. I don't think anyone has determined what the ribs were for. They date to the 1890's and are not rare.
 

geofrac

Member
Joined
Jun 14, 2019
Messages
15
Reaction score
7
Points
2
That is a CD 106.3. I don't think anyone has determined what the ribs were for. They date to the 1890's and are not rare.
nhpharm:
Thank you, those fins are hard to see in photos. I was thinking their purpose was to aid in installing and removing the insulator, or perhaps designed for a special tool to screw them in and out.
 

nhpharm

Well-Known Member
Joined
Apr 24, 2007
Messages
2,978
Reaction score
1,655
Points
113
Definitely could be. The researchers have looked for years for a patent that might identify what they were for, but it appears to not have been a patented "improvement". I believe they show up on 4 different styles of insulators, all presumably made by the same company.
 

willong

Well-Known Member
Joined
Apr 22, 2009
Messages
1,027
Reaction score
1,001
Points
113
Location
Port Angeles, WA
nhpharm:
Thank you, those fins are hard to see in photos. I was thinking their purpose was to aid in installing and removing the insulator, or perhaps designed for a special tool to screw them in and out.
geofrac,

That was my thought too before even reading your response to nhpharm. Either working barehanded or with gloves on, installing or removing wet, dry, dusty or ice-covered insulators in all types of weather conditions those relatively low ribs would provide a lineman extra purchase* on the otherwise slick glass.

EDIT: Special-purpose pliers or a spanner might be required to exert enough torque if the wooden pins are expanded from moisture. Perhaps something like the soft-jaw connector pliers in photo below, only contoured and notched to accept the "fin" region of the insulator.

1663438585647.png



* a hold or position on something for applying power advantageously, or the advantage gained by such application
 
Last edited:

BillinMo

Well-Known Member
Joined
Jul 28, 2010
Messages
752
Reaction score
78
Points
28
Location
Missouri
That's a CD 121 toll. What you call fins are usually called "ribs" by collectors and they're a characteristic of Duquesne Glass Co. which produced insulators I think the 1890s or so in the Pittsburgh area.

They're unusual, but not rare.
 

Members online

Latest threads

Forum statistics

Threads
83,436
Messages
744,369
Members
24,485
Latest member
Carpenter
Top