Common Styles of 19th and Early 20th Century American
Wing Dividers
It is likely that most dividers and calipers found in this
country in the 18th and first half of the 19th century
were user or blacksmith made or imported from abroad, mainly England. American
manufactured friction dividers are uncommon except for Osborne’s leather
workers models. Most wing dividers and calipers manufactured in America during
the last half of the 19th century and on into the early 20th
century fall into a few broad style categories. The style names listed are my
creations.
Straight-Legged
These dividers are relatively simple in design compared to
the Birmingham and Lancashire models made in England with chamfering and designs
filed into the legs (discussed in an earlier blog post). Characteristics
include:
-
Straight legs usually square in the upper
portion transitioning into a round section below.
-
Small round single/rule or occasionally, as with
a Starrett, a three-leaved box joint. The joints on steel dividers were often
faced with brass washers.
-
A characteristic fine adjustment mechanism usually
consisting of a leaf spring attached to the inside of one leg and an adjustment
wheel on the outside of that leg.
-
The wing held in place by a simple flat thumb
screw.
Many of the earlier versions of this style were made mainly
of brass with steel components and often had patented elements. Examples
include dividers with Sullivan(1880), Miller(1873) and Stoddard(1872) patents.
Later versions were made of steel and were produced by well known manufacturers such as Stevens, Peck, Stow and Wilcox, Sargent and Starrett. Many of these were offered in graduated sizes and produced well into the 20th century.
Bow-Legged
Similar in several respects to the straight-legged, the
major difference of the bow-legged dividers was the design of the legs. The
upper third or so came off at an acute angle from the joint then bent in so the
legs were parallel to each other. The bend was sometimes pronounced, sometimes
more gradual. Here again there were patented versions such as Weatherhead(1873),
Cook(1871) and Copeland(1887). Later versions were offered by the same
companies listed above that produced the straight-legged versions with the
addition of Stanley. Both straight-legged and bow-legged models often came with
replaceable points or pencil holders.
Slot-Winged
This later design was like the straight-legged style, but
the central portion of the wing was cut out and pierced by the locking nut.
These are often light weight tools which don’t seem to show the quality of the
previous two styles. Manufacturers include Schollhorn(LODI) and General.
I should mention that Schollhorn also made a very popular Bernard patent(1905) style of dividers that was not slot-winged as such, but had a triangular open wing.
