FRAME FOR SUPPORTING CANVAS
This invention relates to a kit of parts for making a frame for supporting a canvas, a frame assembled from said parts and an artist's canvas comprising a canvas
/* 5 mounted on said frame.
Conventionally, artist's canvas are prepared by securing a canvas on a frame which is then expanded to tension the canvas. Typically, the frame is made from a kit of parts comprising four mouldings the ends of which
10 are each provided with a tenon which engages in a mort¬ ice in the adjacent mounding when the frame is assem¬ bled. Thus each end of each length of moulding is provi¬ ded with a mortice and a tenon. In addition, the faces of each end of each moulding are mitred. In use, the
15 mouldings are assembled to form a frame. A canvas is then secured to the frame and is tensioned by inserting wedges between the tenons and mortices as required.
Whilst this arrangement has been used for many years it has the disadvantage that highly specialized
20 equipment is required for cutting and shaping the ends of each moulding. As a result, frames are relatively expensive and, more importantly, are only available in a limited number of sizes determined by the manufacturer. Although frames can be obtained to a required size they
25 are very expensive and usually involve a delay of sev¬ eral weeks to obtain.
The present invention, as least in its preferred embodiments, aims to provide a kit of parts which can be readily adapted for making a frame of desired size.
30 According to the present invention there is provi- ded a a kit of parts for making a frame for supporting a canvas, which kit comprises at least one moulding having a groove extending therealong and at least one plate insertable in said groove.
35 Preferably, said plate has two edges which are
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provided with teeth.
In one embodiment, said plate is of substantially triangular shape.
In another embodiment, said plate is of substanti- ally truncated triangular shape.
Preferably, said plate and/or said groove is ta¬ pered.
Advantageously, said kit includes four plates.
Preferably, said groove is defined between a first portion and a second portion and said second portion extends beyond said first portion.
If desired said kit may include four lengths of moulding which may be mitred so that the frame may be constructed to a standard size if required. Preferably, the kit includes at least one packing piece which may comprise, for example a wedge. However, the packing piece may be formed from one or more pieces which are not tapered.
Advantageously, said kit includes at least four packing pieces.
Preferably, said kit includes at least one fastener comprising a first surface, a second surface extending substantially perpendicular to said first surface, and at least one spike extending from said first surface. In a different embodiment said kit includes a single plate which will generally be rectangular.
The kit may also comprise glue and/or canvas and/or means to secure a canvas to said moulding.
The kit may also include a brace. Advantageously, said brace comprises a moulding of generally 'H' shape cross-section having oppositely extending grooves; and a pair of end pieces, each end piece comprising a tongue portion and a pair of legs which can be slid into respective ones of said grooves in said moulding to provide said moulding with tongues
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at each end thereof.
The present invention also provides a frame when made from a kit in accordance with the invention.
The present invention further provides an artist's canvas comprising canvas mounted on a frame in accor¬ dance with the invention.
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For a better understanding of the invention refer¬ ence will now be made, by way of example, to the accom¬ panying drawings, in which: -
Figure 1 is a perspective end view of a first embodiment of a moulding used in the construction of a frame in accordance with the present invention;
Figure 2 is a plan view of a plate used in the construction of a frame in accordance with the present invention; Figure 3 is a fragmentary view showing a corner of a frame in accordance with the invention made using the moulding shown in Figure 1 and the plate shown in Figure 2;
Figure 4 is a perspective end view of a second embodiment of a moulding used in the construction of a second embodiment of a frame in accordance with the present invention;
Figure 5 is a perspective view of a plate used in the construction of the second embodiment of a frame in accordance with the invention;
Figure 6 is a fragmentary view showing a corner of a second embodiment of a frame in accordance with the invention using the moulding shown in Figure 4 and the plate shown in Figure 5; Figure 7 is a perspective end view of a third embodiment of a moulding used in the construction of a third embodiment of a frame in accordance with the present invention;
Figure 8 is a perspective view, to a much reduced scale, of a plate used in the construction of the third embodiment of a frame in accordance with the invention;
Figure 9 is a fragmentary view showing a corner of a third embodiment of a frame in accordance with the invention using the moulding shown in Figure 7 and the plate shown in Figure 8;
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Figure 10 is a perspective end view of a fourth embodiment of a moulding used in the construction of a fourth embodiment of a frame in accordance with the present invention; Figure 11 is a perspective view of a plate used in the construction of the fourth embodiment of a frame in accordance with the invention;
Figure 12 is a perspective view of a fastener;
Figure 13 is a side elevation of the fastener shown in Figure 12;
Figure 14 is a fragmentary view showing a corner of a frame in accordance with the invention using the moulding shown in Figure 10, the plate shown in
Figure 11 and two fasteners as shown in Figures 12 and 13;
Figure 15 is a perspective view of one end of a moulding for forming part of a brace;
Figure 16 is a perspective view of an end piece for use with the moulding shown in Figure 15; and Figure 17 is a fragmentary perspective view of one side of a frame provided with the moulding shown in Figure 15 and the end piece shown in Figure 16.
Referring to Figure 1 of the drawings, there is shown a moulding which is generally identified by the reference numeral 11. The moulding 11, which is made of wood, has an upper portion 13A and a lower portion 13B which define a groove 12 therebetween. The upper surface of the upper portion 13A slopes towards the opening of the groove 12 as shown. Figure 2 shows a plate 14 which is of generally truncated triangular shape in plan. The edges 15 and 16 of the plate are generally perpendicular to one another and are each provided with a multiplicity of teeth 17.
In use, the moulding 11 is first cut to the re- quired lengths to suit the size of frame required. The
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lengths are then mitred and arranged in the form of a frame 18. Four plates 14 are then lightly inserted into the grooves 12 at the corners of the frame 18 as shown in Figure 3. The whole frame 18 is then laid on a canvas which is secured to the moulding 11, for example by staples and/or pins. The plates 14 are then gently tapped in the direction of arrow A in Figure 3 with a hammer. As the plate 14 moves into the corner the sides of the frame 18 separate thereby tensioning the canvas. The teeth 17 on the plate inhibit the plate returning to its original position.
If desired glue may be used to secure the plate 14 to the moulding 11 in its final position. Various modifications to the embodiment described are envisaged, for example the teeth 17 could be omitted and the plate 14 simply made a tight fit in the groove 12. If desired, the groove 12 and/or the plate 14 could be tapered. In such embodiments the use of glue and/or pins to secure the plate 14 to the moulding 11 would be most desirable to prevent shrinkage of the plate 14 (which is conveniently made of wood) releasing the tension.
* * * Referring now to Figure 4, the moulding 21 is generally similar to the moulding 11 in that it has a groove 22. However, the upper portion 23A of the mould¬ ing 21 is not sloped.
The plate 24 shown in Figure 5 is generally similar to the plate shown in Figure 2 except that it is comple¬ tely triangular in plan and the edges 25 and 26 are not provided with any teeth.
In use, the moulding 21 is cut and mitred to the required lengths which are then laid out to form a frame 28 (Figure 6). Four plates 24 are then inserted in
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respective corners of the frame 28 which is then laid onto a canvas which is secured to the frame 28. Packing in the form of wedges 29 are then inserted between the mitres of the sides of the frame 28 as shown to tension the canvas. Once in position, the wedges 29 are ideally secured to the plates 24, for example by glue.
If desired non-tapered packing pieces could be used in place of the wedges 29.
Whilst the embodiment shown in Figures 4 to 6 will work it has some disadvantages, particularly in the environment of a commercial framing establishment.
In particular, in such environments guillotines are usually used for cutting mouldings. Ideally the upper portion 23A and lower portion 23B of the moulding 21 should be as wide as possible and the groove 22 as deep as possible to give maximum rigidity to the frame 28. However, such mouldings can collapse when cut by a guillotine.
This problem can be substantially overcome by using the moulding 31 as shown in Figure 7. It will be seen that the upper portion 33A of the moulding 31 is shorter than the lower portion 33B. This moulding 31 can be readily cut by a guillotine with little or no risk of collapse. At the same time the overall rigidity of the final frame is significantly enhanced.
Once cut and mitred to the required size the lengths of moulding are arranged in a rectangle around the periphery of a single rectangular plate 34. The frame 38 thus formed is then placed on a canvas with the lower portion 33B of the moulding 31 in contact with the canvas. The canvas is then secured to the frame 38 by staples and/or tacks and/or glue and a wedge 39 is pushed home on top of the plate between adjacent upper portions 33A of the frame 38. The wedges 39 are then glued in position.
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This later arrangement has significant advantages. In particular, conventional artist's canvases, and those purchased as described with reference to Figures 1 to 6 have the disadvantage that they are often picked up by inserting the fingers between the frame and the canvas, this produces a stretched area which spoils the canvas. By having a solid back the artist's canvas cannot be picked up with the fingers between the frame and the canvas. In addition the artist's canvas can be stacked and kept more safely.
In the embodiment shown in Figures 10 to 14 the moulding 41 is similar to the moulding 31 shown in Figure 7 except that the groove 42 is tapered.
Once cut and mitred to the required size the lengths of moulding 41 are arranged in the form of a frame 48. Four plates 44 are then lightly inserted into the grooves 42 at the corners of the frame 48 as shown in Figure 14.
The whole frame is then laid on a canvass which is secured to the moulding 41 by staples and/or tacks and/or glue.
The plates 44 are then tapered into the corners to stretch the canvas. Whilst the taper on the grooves 42 should be sufficient to hold the frame 48 in the desired position there is always a risk that the plates 44 (which may themselves be tapered) will work loose. For this reason it is desirable to secure the plates 44 by, for example staples and/or tacks and/or glue.
A particularly useful fastener is shown in Figure 12. In particular, the fastener, which is generally identified by reference numeral 20, comprises a bent piece of metal having a first surface 21 and a second surface 22 extending generally at right-angles to said first surface 21. A plurality of spikes 23 are pressed out of the first surface 21 as shown. In the embodiment
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shown, one spike 23A points forwardly, whilst the spikes 23B to either side are angled at about 45° with respect to the spike 23A.
In use, the leading edge 24 of a fastener 20 is inserted between the plate 44 and lower portion 43B of each moulding and then tapped into place by hammering against second surface 22. The spikes 23 retain the plate 44 in position.
With larger frames it is necessary to provide one or more braces which extend across the frame. Conven¬ tionally each end of such braces is provided with a tenon which slots into mortices cut in the frame.
Figure 15 shown a moulding 101. The moulding is of generally 'H' shape cross-section having grooves 102A and 102B disposed on opposite edges thereof.
Figure 16 shows an end piece 103 which includes a tongue portion 104 from which extend two legs 105 and 106.
In order to brace, for example the frame 18 shown in Figure 6 the moulding 101 is first cut to the re¬ quired length. The legs 105 and 106 of end piece 103 are then slid into grooves 102A and 103B to provide the moulding 101 with a tongue 104 at one end thereof. A similar end piece is then mounted on the other end (not shown) of the moulding 101 to form a brace.
During construction the tongue 104 is simply slid into the groove 12 of the moulding 11 and secured in place by, for example packing in the form of a wedge 107
(Figure 17). Again, pins and/or glue may be used to secure the brace in position.
It is also possible to insert braces into a comple¬ ted unbraced frame. Insertion may require a temporary small distortion of the frame. Alternatively the brace may be cut a fraction short and wider wedges used. Finally, although it is normally desirable to be
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able to stretch the canvas certain types of canvas have a natural elasticity which enables them to be stretched as they are mounted on the frame. Similarly, it is sometimes possible for a skilled craftsman to mount a canvas on a frame sufficiently taut for stretching to be unnecessary. It is thus not essential to use a wedge in all cases.
The term "canvas" as used herein includes canvasses for painting, tapestry and needlework.
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