Vol. 2, Issue 1
Blaisdell Marking Gauge
a gauge as a fixed measuring device is something that
almost all woodworkers need to do. Someone will cut a
piece of wood to a specific size, just to scribe repetitive
measurements onto the workpiece. Homemade examples sometimes
exhibit a greater variety of patterns and construction
styles than commercially made marking gauges.
A. H. Blaisdell of Massachusetts patented (#79,052) this
carpenter's marking gauge on June 23, 1868. Previous patents
on tools of this sort had not addressed the scribing of
lines accurately and consistently on convex and concave
surfaces. Blaisdell sought to alleviate this situation
by having moveable arms on his marking gauge. These arms
contacted the edge of the workpiece at some distance from
the marking point, but still allowed for accurate scribing.
The main goal in producing this complicated marking gauge
is clearly described in the patent. It was intended for
"drawing marks parallel to the straight or curved
edge of a board or article". The moveable arms were
articulated and had the ability to follow irregular surfaces
and bear on the edge with more than a single contact point.
There was also a locking thumbscrew that maintained a
repeatable radius for production work.
The Blaisdell gauge came in two sizes, the smaller being
the more rare of the two. The tool shown here is the larger variety. Both sizes were constructed
using brass and rosewood. When clean and with good patina,
this combination gives a most pleasing appearance and
makes the marking gauge a highly desirable piece for tool
collectors. The patent information is always found on
one of the brass thumbscrews. The unusual configuration
of the moveable arms and fingers, and the resulting actions
when used as intended, are quite fascinating.