US2002580A - Making lasts - Google Patents

Description

May 28, 1935. c, MacDQNALD 2,002,580

MAKING LASTS Filed Aug. 8, 1952 4 Sheets-Sheet 1 M y 28,1935. c. K. Ma cDONALD 2,002,580

' MAKING LASTS Filed Aug. 8, 1932 4 Sheets-Sheet 2 N-mmmw May 28, 1935.

C. K. M DONAL-D MAKING LASTS Filed Aug. 8; 1932 4 Sheets-Sheet 3 May 28, 1935. I c, MacDQNALD 2,002,580

MAKI'NG LASTS Filed Aug. 8, 1952 4 Sheets-Sheet 4 Patented May 28, 1935 UNITED "STATES PATENT OFFICE MAKING LASTS Application August 8, 1932, Serial No. 627,8'li) ence particularly to the manufacture of lasts and last models, adapted for use in the manufacture 5 of both ordinary shoes and orthopedic shoes of the character disclosed in United States Letters Patent No. 1,039,396, granted September 24, 1912, upon an application of Mathew Hilgert. It should be understood, however, that in various of its aspects the invention is adapted to use in the manufacture of shoes of other types.

It is well known by foot specialists and doctors generally that feet of different individuals differ widely in shapes and proportions as well as in sizes and that even the two'feet of a given individual will oftenexhibit such differences. The diversity in outline of the feet of different persons partly congenital and is partly caused by diferent foot postures and by the characteristic salts and dilferent foot activities of different individuals. One example of the diversity in the shape of feet may be found from a comparison of the upper surfaces of various feet. This upper surface or dorsum curves in two directions, one time starting at the heads. of the metatarsal bones and extending backwardly, and the other curve starting at the inner side of the foot and extending outwardly around the foot. This curvature is commonly referred to as the instep and its shape is .governed largely by the height of the longitudinal arch. The curvature of the instep not only varies markedly in the feet of different individuals but usually differs more or 40 from fat, muscular or flabby feet. Any of these variations may exist in a normal foot since a footis considered normal to an individual if it is capable of effectively performing its work, that is, if it is capable of supporting the weight of the body, taking part in normal locomotion, and exhibiting the range of foot movements natural to a normal foot. v LAt the present time most of the shoes manufactured in'this country are made on commercial wood lasts which are produced on last-making machinery constructed and arranged to turn wood lasts from selected last models. The various models utilized in making these wood lasts have certain standard measurements, 811011,!01' ex- 55 ample, as the girths at the ball, waist and instep,

though differing considerably in shape and style in other respects. The lasts are graded from sizes appropriate for the largest feet to sizes appropriate for the smallest feet for which shoes are made commercially, the grading scheme being 5 irrespective of the styles of the lasts. It follows that the measurements of commerciallasts are substantially the same for all styles of shoes, that is to say, all lasts of a given length and width will have substantially the same basic measurements at the ball, waist and instep, since these measurements, having been found suitable for most feet, have been standardized. This does not mean that commercial lasts do not vary somewhat in shape at other portions thereof, for example, at the toe portions which may be a number of different shapes depending on the particular style of shoe desired, but it simply means that the portion of a last which determines its size with respect to the foot and which, therefore, determines the fit of the shoe, namely, that portion extendingbetween the ball line and the heel end of the last, has substantially the same basic measurements in all commercial lasts of the same length and width regardless of their styles.

From the above it will be seen that, although commercial lasts reproduced from models on the usual last-making machinery may be properly suited to feet which are perfectly regular in shape, yet the present system of last-making does not provide lasts upon which to make shoes suitable for feet which, although normal in so far as their capacity to support the weight of the body and to effect locomotion is concerned, are nevertheless different in shape from the generality of feet which agree with the standard last measurements at the ball, waist and instep portions of the feet. Moreover, this system can not, of course, produce lasts suitable for feet which are completely broken down at the main arches or which are aiiiicted with malady of the muscles, ligaments, or bones that make up and support .these arches. Consequently, many cases exist where an individual is compelled to wear shoes which, although having the standard measurements referred to, are nevertheless the wrong kind of shoes for him to wear because they do not conform properly to the shapes ofall portions of his feet. Such shoes will not only be uncomfortable and irritating to his feet but may eventually bring on serious foot ailments. Many times foot ailments of a minor character have become chronic or even permanent because the persons amicted could not get shoes which fitted their feet properly in all respects.

It is an object of the present invention, therefore, to provide an improved process by which lasts may be made for use in the manufacture of both ordinary shoes and orthopedic shoes, as well as for use as models from which to make wood lasts for use in the manufacture of such shoes,

the lasts being shaped to conform to the peculiar characteristics of the particular feet for which they are made, and, in the manufacture of orthopedic shoes, being adapted, if desired, to provide a definite amount of extra space for the insertion of a special filler piece between the foot of the wearer and the inside tread surface of the sole of the shoe.

In the practice of the present invention a novel method is employed for obtaining a last which is appropriate to the'foot of a particular individual, this method consisting in making a cast of a foot, shaping the cast to the form of a last and utilizing the cast as a last or as a model to produces. wood last with the aid of the usual last-making machinery. The lasts produced in accordance with this method are adapted for use in the manufacture bf ordinary shoes and orthopedic shoes.

In one aspect the invention contemplates reinforcing the surface of a cast appropriate in shape to the foot of the individual for whom the shoe is to be made, to produce a last the surface of which will be hard and smooth, and of a consistency that will enable the last to withstand the pressure and strain to which it will be subjected during the manufacture of a shoe, or while it is being utilized as a model for turning a wood last, without becoming broken, cracked, or otherwise mutilated during the operations involved in such processes.

In another aspect the invention contemplates producing an improved last which will be especially useful in the manufacture of orthopedic shoes in which the foot is supported by means of a filler piece inserted between the foot of the wearer and the inside tread surface of the shoe, the last being also adapted for use as a model from which to turn a wood last suitable for making orthopedic shoes. Preferably, and as illustrated, a cast of a foot is supported in a predetermined position above a last bed comprising a rectangular plate of wood or plastic material, the plate being considerably larger in, dimensions than the bottom surface of the cast and having an upper surface shaped to conform to the bottom surface of a regular last which has a toe spring and heel height corresponding to the toe spring and heel height of the cast being used. Plastic material is then added to the bottom surface of the cast to produce a form which will provide extra space in the finished shoe for the insertion of especial filler-piece adapted to support the foot in a properly balanced position in the shoe, the contour of the form being trimmed to the pe of a regular last after the plastic material has set.

A convenient way of carrying out this improved process will now be described, reference being made to the accompanying drawings, in which Fig. 1 illustrates, in side elevation, a plastic cast of a foot properly positioned on the upper surface of a last bed which has a clay fence formed. thereon around the lower portion of the cast;

Fig. 2 is an end elevation of the cast, last bed and fence shown in Fig. 1;

Fig, 3 shows the cast after plastic material has been added to its lower portion to provide sufficient material for shaping the cast to the form of a last;

the reinforcing materials on the surface of the cast;

Fig. 8 is a view similar to Fig. 1 showing a cast of an unbalanced foot supported in predetermined position on pins above the upper surface of the last bed;

Fig. 9 is an end view similar to Fig. 2 showing the position of the heel end of the supported cast;

Fig 10 is a view similar to Fig. 3 showing the cast after the addition of plastic material to provide sufficient material for shaping the cast to the form of a last which has a form added to its bottom surface to provide a space in the shoe for the insertion of a filler piece;

Fig. 11 shows the cast of Fig. 10 after it has been shaped to the form of a last; and

Fig. 12 shows a completed cast foruse in the manufacture of orthopedic shoes. J

In practicing the method of the present inven tion casts of the feet of the individual for whom the shoes are to be made are obtained from foot molds formed by pouring plastic material around the feet of the individual while' the feet are supported in a molding box of any usual type. In order that the casts will conform to the shapes of the feet when the feet are supporting the weight of the body and in the positions they are to assume in the finished shoes, the molds are made while the feet are held in normal upright positions, that is, with the vertical center lines at the back of the heel ends at right angles to the tread surfaces of the feet. With the feet in this position, the individual stands so that his weight is supported evenly by both feet, thereby causing the feet to expand slightly at their base portions and to assume shapes natural only when the feet are in weight bearing positions. The natural expansion of feet which are supporting the weight of the body is between one-sixteenth and one-quarter inch.

Since the casts are to be detailed duplications of the feet of the individual when the feet are in the positions they assume in the finished shoes, it is necessary to consider the heights of the heels which are to be attached to the shoes in order that the heel ends of the feet may be positioned properly before the molds are made. Accordingly, the shoes which he is wearing are examined to determine whether the heights of the heels are appropriate to his particular type of foot. If the shoes are found to have heelssuitable in height to his weight and stature, and not causing his weight to be supported unevenly at the differ ent weight-bearing points of the bottoms of the feet, the heel end of each foot is raised relatively to the toe portion an amount equal to the height of such heel, so that each foot will be held sub stantially in the same position when making the impression in the foot mold as it is to assume in the finished shoe. If, however, the heels which the individual is wearing on his shoes are found to be improper for his weight and stature, the heel ends of his feet are raised only an amount which is considered suitable for his particular type of foot. Thusythe impressions obtained in the molds will be exact reproductions of the shapes of the feet of the individual when he is standing with his weight bearing evenly on both feet and with the feet in the positions. they will assume in shoes .having heels suitable inv height to his weight and build as well as to the general condition of his feet. v

supporting its proportionate share of the weight of the body that is, the weight which would naturally fall on that foot when the person is standing normally on both feet.

After the impressions are made the feet are carefully measured and the measurements are recorded on a chart which is used for reference during later steps of the method. Since the impression in each mold is an exact reproduction of the shape of the foot from which it was made, the molds may be used for producing a I pair of casts i0, one cast for each foot, which are exact duplications of such feet. The casts l0, one of which is shown inF'ig. 1, are made in the usual manner by pouring a plastic material into the impressions in the foot molds and allowing the plastic material to set before removing the cast from the mold. They may be made from a plastic material such as plaster of Paris or any equivalent thereof that will harden sufflciently to form a solid article. It has been found in practicing the method of the present invention, however, that a plastic composition known as Hydrocal and consisting of marble dust mixed with a binding agent such as plaster of 'Paris or ypsum is preferable for this purpose because, while it is substantially as light as other'plastie substances of this nature and will harden sufficiently to form a solid cast, it sets without undue brittleness. It is to be understood, however, that the terms plastic material and Hydrocal used in the specification are merely descriptive and are intended to include plaster of Paris or any of its equivalents that can be used for making a cast of a foot. After the casts l0 have set a vertical center line l3 is drawn on the back of the heel portion of each cast, as shown in Fig. 2.

Since the bottom surfaces of the casts are detail duplications of the features of the bottoms of the feet from which they were made, accurate measurements may now be obtained from each cast to determine the position of the transverse arch relatively to the heel end of the foot.

By measuring across the forepart of each cast II, with the cast inverted and positioned .so that the vertical center line of the heel end is at right angles to the horizontal, the positions of .the

' arches relatively to each other and to the heel I lift them into corrective'positions relatively to eachother. Shoes having-a space provided for the insertion of a filler :piece are disclosed in Letters Patent No. 1,039,396 previously mentioned. This lifting of the displaced arches tends to relieve the strain on the muscles and ligaments of the arches and to restore the entire muscular organizationiof the foot to a normal balanced condition.

Two sole patterns II are now made by setting the casts upright on a piece of thin cardboard or paper and tracing a line on the paper around the bottom surface of each cast. The length of each pattern is determined by measuring the length of its corresponding cast with a standard last stick and adding three sizes to the measurement of the cast in order to obtain a lengthsuitable for the sole pattern. This length is then marked off on the paper by measuring from the heel end of the tracing and the toe portion of the marl: on the paper. The toe portion of the sole pattern is gradually tapered until it is appropriate in shape for the foot from which the cast was made. The outline of the other portions of the pattern corresponds. substantially to the measurements and contour of the bottom surface of the foot. The two patterns are then cut out on the lines thus drawn.

' The next step in the method is to produce a the tracing is extended until'it coincides with pair of casts which will be appropriate in size and shape to the feet of the individual for whom the shoes are to be made. One of the sole patterns II is placed on the upper surface of a last bed l2 comprising a rectangular plate of wood or plastic material, theplate being considerably larger in dimensions than the bottom surface of the cast. The upper surface of the last bed or plate, as shown in Fig. 1. is shaped to conform to the bottom surface of a regular last having a toe spring appropriate for the shape of the cast being used. The portion of the last bed which supports the heel end of the cast is so formed as to correspond in thickness to the height of heel desired on the finished shoe so that the cast may be positioned longitudinally approximately at the same angle at which "the foot is to be supported in the finished shoe.

If the measurements of the bottom surfaces of the casts indicate that no unbalanced conditions exist with respect either to the longitudinal or the transverse arches of the feet, each cast is positioned directly on the paper pattern. Since filler pieces will not be required in the finished forcing the cast may be begun as soon as the cast has set sufficiently to permit such operations to be performed.

After the cast has been placed on the pattern II, a clay fence 20 is built on the last bed it around the cast ll to form an enclosure completely around the base of the cast, a modeling clay such as plasticine being used for this pur-- pose. The fence should extend upwardly from the last bed a distance approximately equal to half the. height of the cast and should correspond in outline to the contour of the paper pattern ll. Also, the fence should be built as close to the edge of the sole pattern'as can be done with-' out disturbing either the pattern or the cast. Fig. 1 shows the cast positioned on the last bed and having the fence built around the pattern to form an enclosure around the cast.

HydrocaP'fl is now poured into the enclosure thus formed to fill the spaces between the last bed If and the bottom surface of the cast M. The toe and heel portions of the cast are also covered with Hydrocal to fill in the depressions and irregularities formed by the toes at the forepart of the cast, and the inwardly curved portions at the base of the back of the heel. The foot being normal and the cast having been placed directly on the paper pattern, the only spaces that will exist between the cast and the upper surface of the last bed are under the arched portions of the bottom surface of the cast and beneath the toes. After the Hydrocal has set, the cast is removed from the last bed together with the paper pattern, the latter now adhering to the bottom surface of the cast as shown in Fig. 3. The length of the cast will, of course, be increased at its lower portion by an amount corresponding to the length of the enclosure or fence built around the paper pattern.

The next step in the method of making lasts disclosed herein consists in shaping the bottom of the H'ydrocal cast ii] to the contour of the sole pattern H which has adhered to the bottom surface of the cast, and in rounding and shaping the toe and heel portions of the cast to the form of a regular last in accordance with standard last measurements computed from the measurements of the foot which were taken from the original cast. This step is performed by means of scrapers or hand tools suitable for the purpose, for example, knives and files. Care must be taken in performing this step of the process to remove only such material from the lower portion of the cast as will produce a cast corresponding in shape to a regular last while being especially adapted at its upper portion to meet the requirements of the particular foot for which it is to be used. "Figs. 4 and 5 show a "HydrocaP cast 29 at this stage of the process and it will be noted in Fig. 4 that the upper portion 21 of the cast has been made to correspond in shape to the cone of a regular last.

After the shaping or forming operation has been completed, the sole pattern, which until now has adhered to the bottom of the cast, may be torn off, since it has served its purpose and is of no further usein the process. The other cast it of the pair should, of course, be prepared in a similar manner so that there will now be completed a pair of last-shaped Hydrocal casts 25 corresponding in size and shape to the feet of the individual for whom they were made.

The Hydrocal casts 26 are now ready for the final steps of the process disclosed herein and, accordingly, each cast is covered with textile fabric material 28, such as a sock or stocking, which is drawn tightly over the surface of the cast and firmly secured at the top by suitable means such, for example, as a cord or a piece. of wire. The fabric material utilized in this step of the process should be woven or knitted and of such texture that it will yield and stretch sufllciently to hug the cast tightly and smoothly without wrinkling, folding or becoming otherwise irregular in shape as it is pulled over the cast. It will be understood, however, that the present invention is not limited in its scope to the use of a sock or stocking for covering the cast but is intended to include any fabric material which is sufllciently yieldable to give the desired results. The terms sock" and stocking, therefore, are used herein in a comprehensive sense to include any fabric material of this general'nature. Whenfabric materials which do I. not conform naturally to the shape of a foot in the manner of a stocking are used, however, it will be necessary to cut them to approximately the shape of the cast which is to be covered and to secure them together in some way, for example by stitching, to form one complete covering before they are drawn over the cast. Also, such materials should be cut a little under size so that they will stretch when they are drawn over the cast to hug it tightly at all points.

After the fabric material has been drawn over the cast and secured at the top in the manner described, the cast is treated with a stiffening solution 30 (Fig. '7), containing cellulose or a derivative thereof dissolved in a suitable solvent, this solution preferably being of such nature that it will penetrate into the material and saturate all portions of thefabric covering so that when the solvent contained in the solution has evaporated, the fabric will stick tightly to the cast and will harden thereon to form a solid wall or shell on the outer surface of the cast. This stiffening solution may be applied to the fabric material by means of a brush or in any convenient manner that will spread the solution evenly over all portions of the cast.

Substances which can be used for this purpose are numerous since many coating solutions containing cellulose derivatives such as cellulose esters, for example pyroxylin, may be applied to fabric materials in the manner described, and will, upon evaporation of the solvents contained therein, harden suiiiciently to produce the desired results. It has been found in practice that pyroxylin dissolved in acetone or other suitable solvent provides an excellent coating solution which can be applied conveniently to the fabric material covering the cast and that this solution will harden sufficiently upon evaporation of the solvent to produce a smooth, solid coating on the surface of the cast. The term pyroxylin lacquer, however, as used hereinafter in the specification and claims, is intended to include not only pyroxylin dissolved in acetone but any coating substances containing cellulose or a derivative thereof dissolved in suitable solvents. I

When the coating of stiffening solution which has been applied to the fabric covering of the cast has completely dried out, a second coating of the solution is brush-ed over the first coating. The second coating of stifiening solution, however, will not penetrate as completely into the fabric material as the first coating did but will remain more on the surface and, consequently, will act to coat the cast with a fairly uniform covering of pyroxylin, thus giving the surface of the cast a smooth and somewhat glossy appearance after the solvent has evaporated. After allowing sufficient time for the second coating of stiffening solution to become thoroughly dry, a second stocking 32 is pulled over the cast, this stocking covering the cast in the same manner as before and beingfastened at the top by a cord or wire. The second stocking will also have a tendency to stretch and hug the surface of the cast, thus insuring a smooth, snug fit at all curved or hollow portions of the cast. A coating of pyroxyline lacquer 34 is now brushed over this stocking and, after this coating has penetrated into thefabrlc and has thoroughly dried so that the cast presents a hard and comparatively' smooth surface, a second coating is applied to cover the cast in precisely the same manner as was described in connection with the treatment of the first stocking. The second coataooasao dry. The finished cast 36 (see Hg! is now in condition to be used, having a solid HydrocaP' core and being reinforced on its surface with a plurality of coatings of fabric impregnated with hardened pyroxylin.

It has already been pointed out'that if the measurements of the bottom surface of the cast indicate that .the feet are defective or unbalanced with respect to the main arches, a somewhat different mode of procedure is necessary to produce casts suitable for such feet. The method in this case differs only in the step which involves the positioning of the cast on the last bed prior to the addition of the plastic material required for forming the cast to the shape of a last. Accordingly, the manner of positioning a cast of a defective foot on the last bed will now be described.

As stated, if the measurements indicate that the feet of the-individual are unbalanced with respect to the main arches, extra plastic material or a form must be added to the bottom surface of each cast in order to provide extra space in the finished shoe for the insertion of a filler piece especially adapted to support these arches and to lift them into normally balanced positions. The forms are made to correspond in dimensions t the material of the filler pieces.

Figs. 8, 9, 10 and 11 of the drawings illustrate the manner of positioning and balancing a cast 38 of a deformed foot above the upper surface of a last bed. A pin 42, positioned on a sole pattern 44, supports one of the casts 38 at the central portion of the heel end of the cast while the opposite sides of the forepart of the cast. are supported by pins 46 and 48. The lengths of the pins upon which the cast 38 is supported are determined by the thickness of the filler piece or inner-mold desired in the finished shoe. It has been found in practice that the best thickness for the fillerpiece is approximately one-eighth of an inch under those portions of the foot which are substantially normal provided, of course, that no'leg shortage exists which would require a thicker filler-piece to support the foot of the shorter leg. A thickness of one-eighth of aninch will provide suificient support for normal parts of the foot while allowing the filler piece to be made thicker under abnormal portions in order to provide. proper support without causing undue bulkiness or clumsiness in the shape of the finished shoe. Consequently, the pin or pins supporting the cast under those portions corresponding to the unbalanced portions of the foot should be cut to such lengths relatively to the one-eighth inch pins that, when the three'pins' are properly located under the bottom surface of the cast at' points corresponding to the three weight-bearing points of the bottom surface of the foot, the cast will be balanced with the back of its heel end in anormal upright position with the vertical center line 50 on'the back of. the heel end of the cast at right angles to the base of the last bed 40, as shown in Fig. 9. Thus the cast of a defective foot is balanced in a position which corresponds to the position in which the impressions of the feet-were made and also to 'the position in which it is desired that the foot will be supported in the finished shoe.

After the cast has been properly balanced in the banner described, the remaining steps of the process disclosed herein, namely, building a fence 54 around the cast, adding sufficient plastic material 56 to permit the cast to be shaped to the form of a last, as illustrated by the cast 58 in Fig. 11, and reinforcing the cast with succesprocess of making the cast 36 of a normal foot.

The completed filled pyroxylin casts I6 and Gil are shown in Figs. 6 and 12 of the drawings.

Since the casts have hardened outer surfaces i which are strong enough to withstand theusual pressure and strain incident to the manufacture of shoes, they may, if desired, be used as lasts in the manufactureof ordinary shoes or, if they have been made by the process herein disclosed which provides extra space in the shoe bottom for the insertion of a filler piece, they may be used as lasts in the manufacture of orthopedic shoes for the feet of the individual for whom the casts were made. I

As stated, the method herein disclosed also contemplates using the casts as models from which to turn wood lasts with the aid of the usual last-making machine. Lasts obtained by the use of such models will include the peculiar characteristics of the feet of the'individual for whom the casts were made so that shoes produced on such' lasts will fit the feet properly. The special shapes of the lasts obtained by practicing the present method assures producinga when the individual is sitting down and the weight of the body is taken off the feet, but which will be equally comfortable when the individual is standing and the weight of the body is bearing directly on both feet, or when he is walking and the weight of the body is hearing first on one foot and then on the other. If the feet of the individual are defective with respect to the arches or the cords and ligaments which support the arches, properly fitting orthopedic shoes may be made which will provide extra space for the insertion of filler pieces to support the feet in order to assist in correcting whatever defects of this nature may exist.

While the method as disclosed herein contemplates applying two layers of fabric material impregnated with a liquid stiffening solution to the cast, it is to be understood that two layers of cloth and stiffening solution are used merely to reinforce the surface of the cast to a greater degree than one layer would reinforce it. Ac-

cordingly, ifone layer of reinforcing materials is found to provide a sufficiently solid covering on the surface of the cast, additional layers of reinforcing materials may be dispensed with. Conversely, if two layers are found to be insufllcient, additional layers of reinforcing materials may be applied to the surface of the cast.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. That improvement in methods of making lasts which consists in making a cast of a foot adding material to the lower portion only of said cast, and shaping the cast to the form of a last.

2. That improvement in methods of making lasts which consists in making a plaster cast of a foot from an impression taken while the foot is sustaining the weight of the body, adding and shaping the cast to the form of a last.

3. That improvement in methods of making lasts which consists in producing a model by making a cast of a foot from a mold obtained while the foot is supporting the weight of the.

' done in accordance with measurements taken from the foot. v

5. That improvement in methods of making lasts for use in the manufacture of orthopedic shoes in which the foot is supported by means of a filler piece which consists in making a cast of a foot, adding plastic material to the bottom surface of the cast so that a cast may be made which corresponds in dimensions to the dimensions of the original cast plus the filler piece, and shaping the last-mentioned cast to the form of a last.

6. That improvement in methods of making lasts for use in the manufacture of orthopedic shoes in which the foot is supported by means of av filler piece which consists in making a cast of a foot which is supporting the weight of the body," adding to the bottom surface of the cast plastic material to produce a cast which corresponds in dimensions to the dimensions of the foot plus the filler piece, and shaping said cast to the shape of a last which will provide space for a filler piece in the bottom of a shoe 'made thereon.

7. That improvement in methods of making lasts for use in the manufacture of orthopedic shoes in which the foot is supported by means of a filler piece which consists in producing a model by making a cast of a foot which is in the position that it is to assume in a finished shoe, adding to the bottom surface of the model a form which corresponds in dimensions to the material of the filler piece, and shaping the model to the form of a last'thereby producing a model from which to obtain a wood last.

8. That improvement in methods of making lasts which consists in making a cast of a foot, adding material to the lowerportion of the cast, shaping the cast to the form of a last, and reinforcing the outer surface of the cast with a stiffening composition. v

9. That improvement in methods of making lasts which consists in making a cast of a foot which is supporting the weight of the body, adding plastic material to the toe and heel portions of'the cast, shaping the cast to the form of a last, and reinforcing the surface of the cast with a stiffening medium.

' 10. That improvement in methods of making lasts which consists in making a cast of a foot which is in the position that it is to assume in a finished shoe, adding material to the lower portion of the cast thereby increasing its length,

shaping the cast to the form of a last, and reinforcing the surface of the cast with fabric material saturated with a stiffening solution.

11. That improvement in methods of making lasts for use in the .manufacture of orthopedic shoes in which the foot is supported by means of a filler piece which consists in obtaining a cast of a foot from an impression made while the foot is supporting the weight of the body, adding to the bottom surface of the cast a form which corresponds in dimensions to the dimensions of the filler piece, shaping the cast and form to the shape of a last, and reinforcing the surface of the cast with a stiffening composition.

12. That improvement in methods of making lasts for use in the manufacture of orthopedic shoes in which the foot is supported by means of a filler piece which consists in making a cast of a foot which is supporting the weight of the body and is in the position that it is to assume in a finished shoe, adding to the bottom surface of the cast a form which corresponds indimensions to the material of the filler piece, shaping the cast and form to the shape of a last, and reinforcing the surface of the cast with fabric material saturated with a stiffening solution.

13. That improvement in methods of making lasts which consists in making a cast of a foot, adding plastic material to the cast, and shaping said cast to the form of a last, thereby producing a model for a wood last.

14. That improvement in methods of making lasts which consists in obtaining an impression of a foot while the foot is supporting the weight of the body, making a cast of the foot from said impression, and producing a model for a wood last by adding material to the lower portion of the cast and thenshaping said cast to the form of a last.

15. That improvement in methods of making lasts which consists in obtaining an imprmsion of a foot while the foot is in the position it is to assume in a finished shoe, making a cast of the foot from said impression, adding material to fill in the depressions at the toe and heel portions of the cast, and shaping the cast to the form of a last so that it may thereafter he used as a model for turning a wood last on, a last lathe.

16. That improvement in methods of making lasts for use in the manufacture of orthopedic shoes in which the foot is supported by means of a filler piece which consists in making a cast of a foot, adding to the bottom surface of the cast a form which corresponds in dimensions to the material of the filler piece, shaping the cast and form to the shape of a last, thereby producing a model for a wood last.

17. That improvement in methods of making lasts for use in the manufacture of orthopedic shoes in which the foot is supported by means of a filler piece which consists in obtaining an impression of a foot while the foot is supporting the weight of the body, making a cast of the foot from said impression, adding plastic material to the bottom surface of the cast to 33313531106 a form which corresponds in dimensions to the material of the filler piece, and shaping the cast and added material to the shape of the last.

18.. That improvement in methods of making lasts for use in the manufacture of orthopedic shoes in which the foot is supported by means of a filler piece which consists in obtaining an impression of a foot while the foot is in the posi tion it is to assume in a finished shoe, making a cast of the foot from said impression, adding to cast, shaping the cast to the form of a last, and reinforcing the surface-of the cast with a stiffening composition to produce a model for a wood last 20. That improvement in methods of making lasts which consists in making a castof a foot which is supporting the weight of the body, adding plastic material to the lower portion of the cast, shaping the cast to the form of a last, and reinforcing the surface of the cast with a plu-, rality of coats of stiffening materials thereby forming a model for the reproduction of a wood last.

21. That improvement in methods .of making lasts which consists in making a cast of a foot 22. That improvement in methods of makinglasts for use in the manufacture of orthopedic shoes in which the foot is supported by means of a filler piece which consists in making a cast of a foot, adding to the bottom surface of the cast a form which corresponds in dimensions to the material of the filler piece, shaping the cast and form to the shape of a last, and reinforcing the form to the shape of a last, and reinforcing the surface of the cast with a plurality of coats of pyroxylin covered stiffening materials so that the cast may be utilized as a model from which to turn a wood last with the aid of the usual lastmaking machinery.

24. That improvement in methods of making lasts for use in the manufacture of orthopedic shoes in which the foot is supported by means of a filler piece which consists in making a cast of a foot which is supporting the weight of the body and is in the position that it is to assume in a finished shoe, adding to the bottom surface of the cast a form which corresponds in dimensions to the material of the filler piece, shaping the cast and form to the. shape of a last, reinforcing the surface of the cast with fabric materials saturated with a solution of cellulose or a derivative thereof thereby stiffening said cast so that it ma be utilized as a model.

25. That improvement in methods of making lasts which consists in making a cast of a foot, adding plastic material to the toe and heel portions of the cast, shaping the. cast to the form ,of slut, and reinforcing the cast with fabric material stiflened with a solidifying solution of cellulosic materials.

' 26. That improvement in methods of making lasts which consists in making a cast of a foot from an impression taken while the foot is supporting the weight of the body, adding plastic material to the toe and heel portions of the cast, shaping the cast to the form of a last, and reinforcing the cast with layers of fabric saturated with a solution of pyroxylin.

27. That improvement in methods of making lasts which consists in making a. cast of afoot from an impression taken while the foot is suplasts which consists in making a cast of a foot from an impression taken while the foot is in the position it is to assume in a finished shoe, adding material to the toe and heel portions of the cast, shaping the cast to the form of a last, fitting a stocking on said cast, stiffening the stocking with a plurality of coats of pyroirylin lacquer, fitting a second stocking on the cast, and stiffening the second stocking with a plurality of coats of pyroxylin lacquer to form a hard coating on the surface of the cast.

29. That improvement in methods of making lasts for use in the manufacture of orthopedic shoes in which the foot is supported by means of a filler piece which consists in making a cast of a foot from an impression taken while the foot is supporting the weight of the body, adding to the bottom surface of the cast a form which corresponds in dimensions to the material of the filler piece, shaping the cast and form. to the shape of a last, and reinforcing the cast with knitted fabric material stiffened with a solidifying solution of cellulosic material to form a model from which a wood last may be produced.

30. That improvement in methods of making lasts for use in the manufacture of orthopedic shoes in which the foot is supported by means of a filler piece which consists in obtaining an impression of a foot in a foot mold while the foot is supporting the weight of the body and is in the position that it is to assume in a finished shoe, making a cast of the foot from said impression, adding to the bottom surface of the cast a form which corresponds in dimensions to the material of the filler piece, shaping the cast and form to the shape of a last, and reinforcing the cast with layers of knitted fabric material saturated with a solution of cellulose or a derivative thereof. 7

31. That improvement in methods of making lasts for use in the manufacture of orthopedic shoes in which the foot is supported by means of a filler piece which consists in making a cast of a foot from an impression taken while the foot is supporting the weight of the body and is in the position that it is to assume in a finished shoe, adding to the bottom surface of the cast a form which corresponds in dimensions to the material of the filler piece, shaping the cast and form to the shape of a last, fitting a sock over said cast, impregnating the sock with a plurality of stiffening coatings of pyroxylin lacquer, fitting a second sock over the cast, impregnating .said second sock with a plurality of coatings of pyroxylin lacquer thereby producing a model from which a wood last may be obtained with the aid ofthe usual last-making machinery.

32. That improvement in methods of making lasts for use in the manufacture of orthopedic shoes in which the foot is supported by means of a filler piece which consists in making a cast of a foot from an impression taken whilethe foot is in the position it is to assume in a fin ished shoe, supporting said cast in a predetermined position above the upper surface of a conform to the bottom surface of a regular last having a toe spring and heel height appropriate for said cast, adding to the bottom surface of the cast a form which corresponds in dimensions to the material of the filler piece, shaping the cast and form to the shape of a last, reinforcing the surface or the cast with a plurality of layers of knitted fabric material, and impregnating each layer with pyroxylin dissolved in acetone to harden said fabric material.

33. That improvement in methods of making lasts for use in the manufacture of orthopedic v shoes in which the foot is supported by means of a filler piece which consists in making a cast of a foot from an impression taken while the foot is supporting the weight of'the body and is in the position that it is to assume in a finished shpe, producing a pattern appropriate in sizefor said cast, locating said pattern on the upper surface of a last bed, said uppersurface being shaped to coniorm to the bottom surface of a regular last having a toe spring and heel height suitable for said cast, supporting the cast in a predetermined position above said pattem, said position corresponding substantially to the position in which the foot is to be supported in the finished shoe, adding to the bottom surface of the cast a form which corresponds in dimensions to the material of the filler piece, shaping the cast and form to the shape of a last, covering the cast last bed, said upper surface being shaped to with a plurality of layers of knitted fabric material, and reinforcing the fabric material with successive coatings of a solution of pyroxylin or other cellulose derivative.

34. That improvement in methods of making lasts which consists in making a cast of a foot and adding suiicient material to the lower portion of the cast to give said portion the shape of a last while retaining the shape of the foot at the upper portion of the cast.

35. That improvement in methods of making lasts which consists in making a cast of a foot which is in weight-bearing position, adding plastic material to the lower portion of the cast while retaining the shape of the foot at the upper portion, and shaping said lower portion to the form of a last.

36. That improvement in methods of making lasts which consists in producing a cast of a foot which is sustaining the weight of the body, adding plastic material to the cast said material covering substantially less than the entire surface of the cast, and shaping the covered portion of the cast to the form of a last while retaining the shape of the foot at other portions of the cast.

3'7. That improvement in methods of making lasts which consists in making a cast of a foot, adding plastic material to the toe portion of the cast, and shaping the cast to the form of a last.

cm'roRD is. MACDONALD.

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