IMPROVE- MENTS IN STRETCHER FRAMES, FOR ARTISTS' USE AND FOR OTHER SIMILAR PURPOSES
Year: 1885

page_text: COMPLETE SPECIFICATION.
I, AARON DRAPER SHATTUCK, of Granby, Connecticut, United States of
America, Artist, do hereby declare the nature of my invention for IMPROVE-
MENTS IN STRETCHER FRAMES, FOR ARTISTS' USE AND FOR OTHER SIMILAR
PURPOSES and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-
My invention relates to improvements in frames used by artists and others for
the purpose of stretching canvas and similar material and is an improvement
pertaining to the device for which letters patent of the United States were granted
to me, dated Feb. 13, 1883, No. 272,162.
My improvement is designed for stretcher frames having mitered corners, with
or without panel backs, and for such frames as are provided with cross-bars, or with
both panel backs and cross-bars.
”
My improvement consists in an improved form of metallic key provided with
plate, slots, and wedge, and the method of adjusting the same to a miter joint, the
object being to do away with former modes of construction, complicated with wooden
keys, the wedge being beveled at its back corner, cut away at its back,, and placed
centrally between the slots in the plate.
My improvement further consists in the application of a cross-bar key to the
cross-bar joint, the object of which is to furnish a permanent metallic cross-bar key
in place of the wooden wedge formerly used.
The object in beveling the back corner of the wedge is to prevent injury to the
canvas when pressed upon from the front. The object in cutting away the back of
the wedge is to dispense with superfluous metal, and at the same time leave a .
projecting heel upon which to strike when it is desired to drive the key forward.
By placing the wedge near the center of the plate, space is allowed for the
insertion of panels without the necessity of cutting a notch in the panel, which is
unsightly and admits dust and moisture, or if preferred the panel may be notched
to receive the wedge, and the heel of the plate made to project backward far enough
to cover the notch after the key is driven forward.
Generally, however, for panel back stretchers, I prefer to cut a mortise or recess
in the frame at each corner to receive the wedge, the latter being centrally joined
...מ

page_text: to a metallic plate provided with converging slots through which screws pass to
fasten the key to the frame. The wedge in this instance is hidden within the miter
joint.
Referring now to the drawings where similar letters indicate like parts in all the
Figures
Fig. 1, is a plan view of a panel back stretcher frame complete, with corner and
cross-bar keys shown, all being in their retracted position.
Fig. 2, is a plan view of a corner of the frame, with the key removed, showing
the manner in which the frame is cut away at the joint to receive, the wedge, when
it is placed forward upon the plate.
Fig. 3, a similar view, showing the construction of frame without notch or panel.
This Figure also shows the method of fastening the frame with nails at the outer
corners to facilitate adjustment of keys, and also to keep the joint from slipping.
Fig. 4, a similar view, in which no notch is shown at the joint, but a notch is
cut in the panel to receive the wedge, which is set well back on the plate, and is
provided with a projecting heel to cover the opening in the panel when the key
is driven forward.
Fig. 5, is a bottom plan view of a corner key detached.
Fig. 6, a top plan view of a corner key slightly modified, two additional slots
being shown.
Figs. 7, and 8, are side elevations of corner keys, detached, illustrating different
positions of the wedge which may be located any where along a. central line
between the converging slots and extending from the point to the heel of the
plate, the wedge being provided in each instance with a cut away continuation or
rib, extending backward, which forms in connection with the heel of the plate a
projection upon which to strike in driving the wedge forward.
Fig. 9, is a plan view of a corner of the frame, with a corner key in position, and
driven forward so as to open the joint, thereby stretching the canvas or other
material upon the frame.
Fig. 10, is a bottom plan view of a cross-bar key, and
Figs. 11, and 12, are respectively, a top plan view, and a side elevation of a
modified form of cross-bar key.
Heretofore when cross-bars have been used, they have been operated by wooden
wedges driven in between the cross-bar and the side pieces. These wedges, as well
as similar ones used in the corners of the ordinary frame joined by mortise and
tenon, were very inconvenient in use, as they were quite likely to split in driving,
and also to shrink and fall out in a short time. These objections are all obviated
by the novel construction of corner and cross-bar keys which I have berein shown.
In the drawings A, indicates the side and end pieces of the frame, all of which
are mitered at their ends as at B. C, is the panel which fits in a groove in the
inner side of the frame in the usual manner, as indicated in the drawing. D, is a
notch or recess at each inner corner of the frame, which is cut through the frame and
receives the wedge of the corner key. In the form shown in Fig. 2, the converging
portion, only, of the recess is cut through the frame, the portion having parallel
sides being cut only to the depth of the panel groove. I preferably, however cut
the recess through at the inner corner, and clip the corner of the panel. In either
case a pocket is formed to receive the wedge.
In the form shown in Fig. 4, the notches in the frame are dispensed with, and
notches D', are cut in the panel to receive the wedges. E, is the plate of the corner
key of any suitable shape, which rests upon the frame. F, represents slots through
the plate which converge toward the outer or forward end of it. On the under
side of the plate, midway between the converging slots, is a wedge G, which
engages recess D, or the inner angle of the frame. This wedge may be located at
any preferred portion of the central line, but when panels are to be inserted,
I preferably locate it forward of the center of the plate, as indicated in Figs. 5,
and 7. When frames are made without panels, I prefer the form shown in

page_text: Fig. 8, the point of the wedge engaging the inner angle of the frame, or a notch
cut to receive it. It will be noticed that the rear end of the wedge is beveled off;
this is in order to prevent any injury to the canvas or other material stretched
upon the frame when it is pressed upon from the front. Back of the wedge and
extending to the rear end of the plate is a rib H, which greatly strengthens the
key, and forms in connection with the heel I, of the plate, a solid projection upon
which to strike when driving the wedge forward to open the joint. The plate is
held to its operative position, by screws or pins K, which pass through slots F, and
engage the wood of the frame-work. The retracted position of the keys is shown
in Fig. 1. As the wedge is driven forward the inclines which constitute the inner
sides of the slots act upon the screws or pins, reciprocally with the sides of the
wedge, to force the joint open as indicated in Fig. 9. Practically, however, the
wedge does this work; the screws acting as guides, and operating to bind the plates
to the frame.
.
As a modification I have shown in Fig. 6, a key plate with two additional slots
which may be found desirable when great stability is required, especially in very
large frames. It will of course be understood that the shape of the plate, the
number of slots, and shape and depth of the wedges are not of the essence of my
invention, as they may be considerably varied without departing from the spirit
thereof.
L, represents the cross-bar. The cross-bar key consists of a plate M, provided
with a strait slot N, and having upon its under side, a wedge 0, which is adapted
to be driven in between the end of the cross-bar and the side pieces of the frame
it being similar in action to the corner key. A recess may or may not be made for
the wedge by beveling off the shoulders of the cross-bar, I prefer, however, to make
the recess, as indicated by dotted lines in Fig. 1. A single screw or pin passing
through slot N, bolds this key in operative position.
In the modification shown in Figs. 9, and 10, the shape of the cross-bar key is
changed so as to permit its attachment to the inner edge of the frame instead of to
its outer side as in Fig. 7.
The improvements herein described, although used in connection with panel
back frames are equally applicable to other frames in which the corners are cut to
a miter. Likewise the cross-bar may or may not be used, it being preferable for
large frames, but in small frames is wholly unnecessary.
As stated above, I do not limit myself to the exact construction shown, as it is
obvious that the details may be considerably varied without departing from the
spirit of my invention.
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
1. The combination with the side and end pieces of a stretcher frame having
their ends cut to a miter, of a corner key having converging slots, screws or pins
which pass through said slots and engage the parts of the frame, and a wedge upon
the under side of the key which is adapted to engage the joint, and be driven
forward to open the frame.
2. The combination with a stretcher frame the parts of which are mitered at
their ends, and the corners of which are provided with recesses as shown, and a
corner key having converging slots through which screws pass, and a wedge
adapted to engage the recess, of a cross-bar extending between the sides, and a
slotted key held in position by a screw and having a wedge adapted to act between
the cross-bar and the frame.
3. The combination with a stretcher frame, and means, for example corner keys,
for opening it, of a cross-bar, and keys consisting of slotted plates having wedges
which pass between the ends of the cross-bar and the frame, and a screw which
passes through the slot to hold the key in place.

page_text: 4. The combination with a stretcher frame having mitered corners and recesses D,
panel C, and cross-bar L, of the slotted metallic keys having wedges whereby the
frame is opened.
5. As a new manufacture, a stretcher key consisting of a plate having converging
slots, a wedge placed centrally or nearly so, and beveled at its rear-end, and a rib
.extending from the wedge to the heel of the plate.
Dated thin 10th of 100%