Mortising Chisel.
Year: 1899

page_text: Date of Application, 16th Mar., 1899-Accepted, 22nd Apr., 1899
Mortising Chisel.
I, Martha LamoNT, of No. 232, Carroll Street, in the Borough of Brooklyn,
City of New York, County of Kings and State of New York, U.S.A., Clerk, do
hereby declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
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This invention relates to chisels, especially such as are intended to me used in
mortising machines, though the chisel may be used by hand.
The object of my invention is to produce a mortising chisel which shall be
self-clearing and which shall cut easily with a minimum amount of strain upon
the chisel and the wood.
Reference being made to the accompanying drawings.
Figure 1 is a perspective view of the chisel.
Figure 2 is a longitudinal vertical section through the chisel.
Figure 3 is a plan view of the chisel.
Figure 4 is a transverse section taken on the line 4-4 of Figure 3.
Figure 5 is an end elevation of the chisel.
Figure 6 is a transverse section taken on the line 6-6 of Figure 3
The body A of the chisel is provided with a longitudinally plane floor, 1, which
constitutes the bottom of the chip-receiving channel B. The floor 1 is of equal
width throughout its entire length and its forward end is enclined or beveled,
terminating at the plane of the under face of the chisel in a sharp edge 2.
The rear end wall 3 of the channel B is upwardly curved. The interior side
walls of the channel are at right angles with the floor 1.
From a predetermined point rearwardly, the side walls of the chisel are curved
over the floor 1, forming thereby flanges 4. These flanges may meet each other
over the floor of the chisel or they may be made with a slight space separating
each other and which latter I consider the preferable way.
The flanges 4, at their lower ends, are given a downward slope following the
direction of the forward end of the floor of the chisel, as indicated by 5, and
terminate in an acute angle with the outer walls of the chisel at the sharp
edge 6 of said wall, which extends beyond the main cutting edge 2 and at right
angles to its plane.
The lower part of the flanges is beveled or undercut forming a knife edge
as at 7. The projecting edges of the chisel at 6, prevent the wood from splitting
in making a thin mortise and the knife edges 7 reduce the strain of the cutting
upon both the chisel and the wood.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:
Claim 1: A mortising chisel having side walls and the upper portions thereof
bent over and horizontal to form flanges, the lower portions of said flanges being

page_text: undercut or beveled to a cutting edge, said cutting edges meeting the outer walls
of the chisel at an acute angle, substantially as described.
Claim 2: A mortising chisel having side walls and the upper portions thereof
bent over and horizontal to form flanges, the lower portions of said flanges being
undercut or beveled to a cutting edge which meets the outer walls of the chisel
at an acute angle, said outer walls extending beyond and being at right angles
to the plane of the main cutting edge, substantially as described.
Dated this 27th day of February 1899.