US2229027A - Method of and means for casting and using molten metal - Google Patents

Description

Jan. 21, 1941.

J. E. PARKER METHOD OF AND MEANS FOR CASTING AND USING HOLTEN METAL Jan. 21, 1941. Q I J PARKER 2,229,021

atented 'Jan. 21, 1941 PATENT OFFICE METHOD OF AND MEANS FOR CASTING AND USING MOLTEN BIETAL James Edward Parker, Washington, D. C. Application March 2, 1938, Serial No. 193,571

12 Claims,

ll/ly invention relates broadly to the art of casting metal and more particularly to methods and means for casting type metal for typ graphical purposes, and the use and employment of the cast metal.

In the prior practice of casting molten metal in a mold or die, molten metal is injected into a mold or die cavity where it is caused to solidify in the shape defined by the mold or die, the solidification in the mold or die being hastened and the characteristics of the mold or die preserved in the metal cast therein by the dissipation to the atmosphere of heat from the. metal and from the mold by several well known means, such as by air blasts, water-circulating systems and the like. The molten metal is injected into the mold or die cavity at a temperature sumciently above the point of solidification to prevent premature solidification and is cooled to the point oi solidification as rapidly as possible by the said heat dissipation. It is evident, therefore, that molten metal'in its course through the mold or die cavity is constantly being deprived of its heat. To compensate for this, the molten metal. upon its injection into the mold or die cavity must necessarily be at its highest temperature at the point of injection.

In the casting of type metal in molds or dies somewhat similar to those used on casting machines known to the art as monotype casters disclosed in Patent 752,814 granted February 23, 1904, and 1,219,956 granted March 20, 1917, the molten'metal is injected at the lower partof a comparatively narrow mold cavity and is forced up to and into contact with a molding surface such as the type face forming matrix seated upon and over the mold cavity; the other molding surfaces including the sides and base of the mold which may be movable with respect to one another. Y

At a given instant, the metal in such a mold will be in a molten state at the lower portion of the mold cavity, that is, at or near the point of injection, while that in other portions of the mold cavity, that is further distant from the point of injection, will have already become solidified due to heat losses referred to-and occurring in its passage through the mold cavity. Because of the comparatively excessive temperature of the metal at the point of injection which exists in order that premature solidification will not occur before the mold cavity is filled and the metal formed to the shape or dimensions defined by the mold cavity, it has been necessary to allow an appreciable period of time, after the mold cavity is filled, for the molten metal at or near the point of injection to solidify (which occurs after the metal has solidified at points further distant from the point of injection) before the mold can be opened, and the solidified metal removed from the mold true to its designed form and shape.

The same conditions obtain in connection with molds other than the particular kind referred to above as an example, regardless of the location of the point of injection with respect to the molding surfaces of the mold cavity.

In practice, variations may occur in thetemperature of the molten metal prior to its in-- jection into the mold cavity as well as in the temperature of the mold itself by reason of the 15 fact that the molten metal injected into the mold cavity (which may be adjustable as to size) may not always be the same amount in every instance, this being dependent upon the size of the cavity.

This adjustable feature is applicable especially in m the process of casting type metal for typographical purposes. It has been impossible therefore to determine the exact instant that the metal within the mold cavity is in a molten state,

is partly molten and partly solidified, or is entirely solidified. 1

As a. result, a time delayelement has been required in the prior practice between successive castings in the same mol which is the maximum time required for the hange of any amount .and overcome production problems arising from the inherent difilculties hereinbefore referred to, by devising present methods and means.

This invention therefore consists substantially in the methods, apparatus and cast products, the

concepts pertaining thereto, the design, structure and arrangement of elements associated with a metal casting process for the practice of my invention, as will be more fully set forth hereinafter, represented in the accompanying drawings and finally pointed out in the appended claims. I

To the extent that the methods and means described herein are applicable to the particular kind of equipment referred to for explanatory purposes, this invention is an improvement thereof, especially with respect to the specific design of mold described in Patents 752,814 and 1,219,956 hereinbefore mentioned, and to the cast products thereof.

One object of my invention is to reduce to a minimum the possibility of metal within a mold cavity being deformed in dimensions, form, shape or other characteristics by reason of the mold being opened in part before the metal has completely solidified.

Another object of my invention is to reduce the temperature of the molten metal at the point of injection without incurring adverse effects due to premature solidification.

It is a further object to obtain more uniform and homogeneous in structure the metal within the mold cavity in its transformation from the molten to the solidified state.

It is a still further object of my invention to provide a method for the casting of metal at a higher rate of speed than heretofore has been practicable and at the same time reducing the tendency of deformations in the metal due to the opening of the mold before complete solidification has been effected and also preventing the product of the mold from being rendered unsuitable for the purposes intended or being restricted in its application and employment, while adding to its usefulness.

Other and further objects and features of my invention will be understood from the specifica tions hereinafter following by reference to the accompanying drawings in which like reference characters have been used to indicate like parts throughout the several views and in which:

Fig. 1 is a view in perspective of casting made pursuant to the herein disclosed method and means with the mold removed and with the casting molten and solidified in part, to diagrammatically show the progressive cooling of the casting;

' Fig. 2 is a perspective view of a casting of slightly different form from that of Fig. 1, such as a space bar, rule or the like member, but disclosing the same general characteristics shown in Fig. 1 and which is advantageously employable with the casting of Fig. 1;

Fig. 3 is a perspective view partly cut away of a mold constructed in accordance with and adapted to utilize the principles of my invention;

Fig. 4 is a cross section sectional elevation view substantially upon line 4-4 of Fig. 3, with surface forming matrix in cross section superposed thereon and-with the electrical circuit being added thereto for additional 'clearness;

Fig. 4a is an elevation view of a portion of the mold shown in Fig. 4 in modified form;

Fig. 5 is a top plan view of the parts shown in Fig. 3, substantially upon line 5-5 of Fig. 4.

- Fig. 6 is a perspective view of a completely solidified metal casting made in accordance with my invention and removed from a mold of the kind shown in Fig. 3. p

Fig. 6A is a modification of Fig. 6, showing a completely solidified metal casting made in accordance with my invention and removed from the mold in the modified form as shown in Fig. 4A:

Fig. 6B is an enlarged and elevation view of a portion of type assembly with the space bars and a portion of the stick, chase, furniture or composing stone being in cross section.

In the drawings, I have illustrated casting metal, a form of casting equipment and the product thereof as used in typography which is typical of that incidental to and employing my invention and in the following description I shall describe the same as applicable to such use, but it is .to be understood that modifications thereof may be made to adapt the same to metal in the process of casting, to casting equipment and to the product thereof other than that of the specific application shown, without departing from the spirit of my invention as defined by the claims appended hereto.

Certain features and characteristics of the type of structure utilized herein to describe my invention have been set forth in detail in the patents hereinbefore referenced (752,814 and 1,219,956) and, to those familiar with the art of casting metal, manifestly the functioning of the several parts and the operation of the specific device referenced and these same particulars with respect to other devices for the same general purpose will be clearly understood without further explanation being considered necessary. It will suffice, therefore, if only such features and particulars thereof as are especially pertinent .to my invention be mentioned, it being understood that my invention is not restricted nor limited to the use or employment of the instrumentalities to which specific references are made.

Heretofore, in the rapid making of a number of castings successively from the same mold, such castings may be deformed in form, shape, dimension or otherwise by opening the mold in part before the metal cast in the mold cavity has solidified substantially below the point of fluidity. I have overcome this problem by the advance solidification of at least a part of the casting and by first opening the mold at the part which has first solidified substantially below the point of fluidity of the metal, and has been confined within the mold in accordance with my invention. In the practice of confining the metal which solidifies earlier, I prefer to employ one or more grooves or protuberances or a combination of such grooves and/or protuberances in the surface of the casting adjacent such part of the mold which first opens and to form said grooves and/or protuberances by corresponding protuberances and/or grooves made a part of casting surface of the mold cavity.

The practice of my present invention is facilitated by my herewith provided method of and means for variably heating different portions of the mold, for exhausting the air or gases from the casting cavity thereof, for visually indicating the character of the casting and for accomplishing other advantages heretofore unattainable.

Any suitable permanent or semi-permanent mold, provided with a cavity of a shape to desirably form the molten metal cast therein, may be adapted for and employed in the practice of my invention with advantageous results.

However, I have obtained excellent results by the construction for, and employment in, such practice as will be disclosed in the following described mold set forth in the drawings and embodying my invention, in which it will be noted that molten metal is injected into mold cavity I through nozzle 2 in base 3 of mold 4, wherein it changes from the molten state as at 5 to the solid state as at 6. The molten metal in its course through mold cavity I gradually fills the cavity 8 and takes the form defined by the molding surface I which may be a type face forming matrix Ia and the remaining mold cavity surfaces 8, 9, l0, H and I2.

The cooling systems, such as air and water, are not shown in connection with mold 4, as molds employing such means for cooling the molten metal within the mold cavity 1! are well lrnown in the art. Accordingly, some such cooling system is considered as being inherent in mold d, if required for any particular application,

although not shown in the drawings. As the result of such cooling action, the molten metal loses its heat as it passes from the point of injection, nozzle 2, to the other end of cavity 0,

such as molding surface 1. Unless the temperature at point of injection 2 is sufficiently high, the molten metal will tend to solidify before reaching surface 7 thus preventing the metal from taking the form defined thereby. If the temperature of the metal at point 2 be suffi- 15 ciently high, the metal will reach surface l in a molten state and will take the designed form determined thereby as well as the shape and dimensions established by the remaining molding surfaces 3, 9, it, ii and I2 of cavity i.

20 Although in a molten state, the metal in cavity i will be at a lower temperature at surface l, which is located at a comparatively great distance from point 2, than at surface it which is located comparatively near point 2. Accordingly, the metal will solidify at surface l before it solidifies at surface it. Before the metal is completely solidified in cavity i, it will be in part solidified as exemplified in Fig. l and Fig. 2

at It and in part molten as exemplified in Fig. l

and Fig. 2 at b.

Metal alloys adapted for type casting purposes expand somewhat in cooling. Molding surface l, such as in type face forming matrix la, heretofore had to remain securely positioned over cavity l until the casting therein had solidified not only at portion It but also at portion 5 because should surface ll be lifted or removed before complete solidification of the metal in'cavity i had occurred, the push of the cooling metal at it would be transmitted to the solidified portion at t which, yielding to the effect of the push, would thus tend to deform the cast metal withrespect to its preferred dimensions, form, shape and other characteristics.

, To overcome this difliculty especially when casting at high rates of speed, I have provided a protuberance in the upper portion of surface d as at it in the vicinity of portion t of the casting metal where solidification of the metal first 50 takes place. This protuberance at it, causing a recess to be formed in the solidified portion t of the casting as at ltd, Fig. l, will engage the recess Eda in the solidified portion t of the casting metal and securely hold the metal in position in cavity l permitting surface 1! to be lifted or removed before the lower portion of the metal as at it Fig. 1 has completely changed from its molten to its ultimately solid state, thus preventing deformation of the metal by the removal 9 of surface l before the metal casting has been completely solidified, and allowing earlier rernval of surface l in the progressive action of opening the cavity l for the removal of the casting.

In order to equalize the strain on the metal when surface 7! is thus removed, a protuberance it may be located in surface 8 to form and engage a recess as at l5a in portion 6 of the cast ing opposed to protuberance l4 and recess Ma m therein. Likewise, protuberances may be -located in surface H and/or I 2 if desired.

Optionally, recesses or indentations in lieu of protuberances may be used in surfaces of the mold cavity in the vicinity of portion 6 of the w'casting such as at M and I5 whereby instead of recesses being made in portion 6 of the casting as exemplified at Ma and Ho Fig. 1, protuberances will be had as at I 4b and IE1), Fig. 2, to permit the same functions to be performed.

Protuberances, such as Mb and IE1), are preferable in some instances to recesses or indentations such as at Ma and I511; forv example, should a particularly or comparatively thin strip of metal be the product of the mold. If .desired or required, any one or more of the protuberances may be removed from the strip after the strip has been ejected from the mold cavity and after the protuberances have served their purposes. The method and means for the removal of the protuberances, if desired, such as from strips, slugs or rules after casting, are so well understood by those familiar with the typographical art that further explanation or description thereof is deemed to be unnecessary.

Through the employment of my method of casting metal as embodied in my invention which includes the process of filling a mold cavity with molten metal and transferring the stress from one surface of the mold as l to another side or a plurality of other sides of the mold as at M and/ or Ii 5 before complete solidification has taken place, it will be now practicable especially in typography to remove a type face forming matrix as la having a molding surface ll, immediately the metal casting has solidified in the vicinity thereof, such as at t, as protuberances (or recesses) such as at it and/or it, co-acting with the recesses as at ltd and/or Illicit (or protuberances as at Mt and/or llib) at the solidified portion of the metal as at it in lieu of molding surface as at l will serve equally as well to retain the solidified portion t of the casting metal in the proper position within the mold cavity [I while the remaining portion of the metal casting such as at it is changing from the molten to the solidified state.

In many kinds of molds, such as the mold d particularly referred to herein,it is essential that removal of one molding surface such as ll be effected before the cast metal can be ejected from the mold cavity i. It will be evident that where such progressive action is involved, the substitution of some means other than molding surface ,as i such as l have disclosed herein as at l t and/or ltfor retaining the casting metal in position within cavity l until complete solidification throughout the mass of. metal has taken place, will facilitate matters and will accomplish one of the objects of my invention.

For typographical purposes, it is customary to have one or more niclns in character type to indicate the correct position thereof in a type form assembly and also the character of the type face. Such identification niclr or nicks can be located in the casting by the niclr pin and/or pins located in the mold cavity IIv such as at it Fig. 4.. For other typographical purposes, it is desirable to have a plurality of recesses and nicks in a casting as at ltd, lite, and Ma, lldb as shown in Fig. 6A. I have provided such additional recesses as shown in casting a Fig. 63, by locating nick pins [3 in such position that the distance between resultant nicks Ma and ll3b and the upper surface or shoulder of casting A is the same as the distance between recesses Ma, and Mia and the lower surface or foot of casting A. As protuberances and/or recesses may be utilized to equal advantage in my invention, a further advantage of the use of protuberances and/ or recesses in resulting castings when juxtaposed for typographical purposes is shown 'n Fig. 6B wherein such several combinations of p otuberances and/or recesses in castings A, B an C are shown as co-acting to retain such several castings in a preferred relationship one, with the other as supported on or by stick, chase or stone D of Fig. 6B, the protuberances or recesses resulting from Id and I5 engaging adjacent recesses or protuberances as in cavity I so that the position of casting A, B or C whether in a type form assembly or in cavity I is determined by the character of the protuberances (or recesses) as I4 or I5, adjacent thereto and engaging or engaged by the casting at portion 6, and not by the surface contacting the casting as at I, thus retaining the casting at portion 6 in a firm or fixed position while at any time that portion 6 is solidified, the surface contacting the upper portion of the casting at I may be repeatedly removed and replaced without affecting the physical characteristics of the castmg. i

The construction of the sides of cavity I can readily be such as toprovide indentations 5a and 5b of Fig. 6A which function to effect the casting metal in a. mold especially adapted to typographical applications. By modification of mold 4, Fig. 3, Fig. 4 and Fig. 5, to include openings generally of the character indicated by 23a, 23b, 23c, and 23d of Fig. 4A, I have made provision for attaching to the casting another protuberance 23c of-F'ig. 6A, comprising a small piece of the metal which may be readily detached from the body of the casting, the presence of which on the casting will visually indicate the character thereof. The formation of piece 23a is shown in connection with the casting of metal A in Fig. 4A.

Thus I have made specific reference to certain characteristics of the molded casting and general reference to the character of the mold for the production of the molded casting, without prejudice to the spirit and intent of my invention.

It will be noted that immediately after the mold cavity I is completely filled with metal and solidification thereof has occurred as at 6 while as at 5 in the vicinity of point of injection 2 the metal may be in a molten state, one side of the molding surface, as I, may be removed. After complete solidification of the metal and the removal of surface I, the cast metal is ready to be ejected from the mold cavity I. This may be eifected by the functioning of one mold part such as H which may be a movable ejector blade serving to thrust the metal toward side II when the mold part there located, such as III which may be a movable cross block, has been moved'out of its interfering position. Before mold parts I! and I8 can function as described above, and after molding surface I has been removed, suflicient time must be allowed to permit complete solidification as at 5. In order to shorten this time element,

if desired, I have provided heating devices I9 and 20 to coact with the cooling system of the mold (not shown) associated with a heating control device 2i and a source of supply 22 for the operation of the heating devices 20 and 2|. An example of the principles involved is disclosed by the drawings in which an electrical system is used for illustrative purposes. I

Through the medium of adjustable control device 2I which I show as being a potentiometer unit, the amount of heat developed by device I9 can be made substantially the same as (position a of device 2|) considerable greaterthan (position b of device 2|) or decidedly less than (position of device 2i) that developed by device 26, for reasons which are self-evident. This differentiation can be controlled to a nicety by device 2I. With device I9 developing greater heat than device 20, it is evident due to the in dicated locations of the devices I9 and 20, that the temperature of the metal at point of injection 2 can now be considerable reduced as the greater heat developed by device I9 at the distant point such as at 71 from point of injection 2 will counteract the tendency towards premature solidification. Therefore due to the less difference in temperature between the metal at 6 and the metal at at a given instant, there will be less delay between the time when the metal solidifies as at I5 and as at 5, and the functioning of parts I! and I8 can follow more closely the movement of mold surface I. Also due to the lower temperature at point of injection 2, the movement of mold surface! need not be delayed. unduly as heretofore to allow for the dissipation of excessive heat from the metal.

Although only two heating devices I9 and 20 are shown, it should be understood that similar devices can be located in any preferred positions within the mold 4 to co-act with the cooling system and furthermore that additional devices may be associated with the heating system such as devices I9, 20, 2| and source .22 to further the function of devices I9 and 20 so that heat will be dissipated therefrom intermittently as and when required for the purpose intended without departing from the spirit and intent of my invention.

In order to provide for a homogeneous mass of metal free from an air or gas content under pressure, I further provide the molding cavity with an outlet 23 which may be connected to a vacuum exhaust system and co-act with other working parts of the. mold so as to not only assist in the displacement of the air or gas by the molten metal within the molding cavity but also assist in the injection of the molten metal into the mold cavity chamber through point of injection 2. r r

With particular reference to casting of type metal in molds of the kind in general referred to specifically hereinbefore, it known and recognized that such molds not pnly are capable of casting type high character type, rules and the like, but also shoulder high and low space type, linera slugs and the like; in many instances, the change from one height to another being en-- tirely automatic in its action. It is to be understood therefore that molding surface I herein before referred to may be representative not only of the type face forming matrix but also of any height determining surface associated with or employed in the mold in connection with the process of casting the metal such as at I6 which may be part of or a section of the mold ejector blade II.

In certain classes of typographical work, it has been found confusing to have a plurality of protuberances or recesses on more than one side of the cast metal. When it is desired to restrict the plurality of protuberances or recesses to but one side of the cast metal for identification purposes and to restrict the quantity of protuberances or recesses on the opposite side to a minimum preserving the equalizing reactance characteristic of opposed. protuberances or recesses to the pushing effect of the molten portion 5 of the casting on the solidified portion 6 of the castlil hill

ing or any other movement of solidified portion 8 within the mold cavity i such as might be occasioned by the removal or movement of molding surface I whatever its character may be with respect to the height of the cast metal, I have found that satisfactory results are obtainable from a practical commercial standpoint by having the recess or protuberance at I4 and the opposed recess or protuberance, if any, at l5 positioned substantially 1% inch above the lower surface l which forms the foot of, type of standard height (i. -e., approximately 0.9186") and of the rules, spacers, quads and other such cast metal employable for typographical purposes; that is as near as feasible, considering other factors entering into the construction and employment of the cast metal such as the fact that some of the spacing castings are of lower overall height than the character castings, to the upper surface thereof. In order to accomplish this, a plurality .of opposed recesses or protuberances may exist with respect to metal cast to the greatest height used for typographical purposes whereas a minimum of such recesses or protuberances may exist with respect to metal cast to the lowest height used for typographical purposes, in which case the distance between the top of the cast metal determined by its particular molding surface such as "l or as it as hereinbefore explained, and a protuberance or recess as the case may be such as at it and/or i5, will be thesame irrespective of the over all height of the particular metal as cast at a time in a given mold such as t. It appears reasonable therefore in certain applications such as particularly referred to herein for explanatory and descriptive purposes, that the protuberance or recess as at it and/or it which functions to retain the metal at portion t in position within the mold cavity i while the lower portion, as at b, is changing from the molten to the solidified state and while the height determining molding surface,

such as l or it, is capable of being removed or moved from its position whereat it serves first to form a part of portion 6 of thecasting metal and without such removal or movement being detrimental to the casting, should be substantially not less than of the overall distance between the two height-determining molding surfaces, such as it and "i, measured from the lower part of the metal as established by the lower molding surface such as ill.

While any one of the aforementioned features will per se assist in the casting of metal at a higher rate of speed than has heretofore been practicable, will result in a cast product having far superior characteristics than heretofore obtainable, and will reduce the tendency (heretofore considered as inherent andunavoidable) of deforming the casting or ofdeformations taking place within the metal during its casting process, in combination these features not only will reduce to a minimum departures from preferredor designed dimensions, form, shape and other characteristics in the product of the mold especially if the mold cavity be partially opened as has been referred to above before complete solidification of the metal has occurred, but also will assure that the product of the mold will be more suitable for the purposes intended than has been possible in prior practice and that the product of the mold will not be restricted by reason of the casting procedure with respect to its ultimate application and employment especially if for typographical usages, although having been cast at a higher -hereinbefore referred to).

rate of speed than heretofore considered or shown as being practicable without having detrimental effects upon the resultant product of the mold.

As metal alloys adapted for type casting purposes expand somewhat in cooling, in this invention the stress in the casting metal is transferred from one point, as l, to another or a plurality of points, as M and/or l5, before complete solidifito additional pressure even while the mold may be opening in part as at i. This is accomplished by means of protuberances (or recesses) I 4 and/or l5 which retain solidified portion 6 in a fixed position while portion 5 is cooling and accordingly expanding and thus subjecting the casting to pressure additional to that which otherwise would obtain. The inclusion of one or more protuberances engaging portion 6 as at l4 and/or it (especially if such protuberances be arcuate), will confine the metal at 6 under the additional pressure (which increases as portion 6 cools to solidity) until portion '5 has cooled to solidity. The diiference in temperature between portions 6 and 5 may be kept to a minimum by the functioning of the. electrical heating system herein disclosed, so that now portion 6 need be but slightly hotter than portion 5 when at that tem-- perature at which the metal will flow freely (such flow being assisted by exhausting gas or air as As one result, my castings not only are of a quality superior to that obtainable heretofore, but also said castings have broader applications and greater usefulness and effectiveness in the art of typography than do castings made in accordance with prior practice.

While I have described my invention in certain of the preferred embodiments and have described a specific application in explanation thereof, I desire it to be understood that modifications may be made to adapt it to other applications and that no limitations on my invention are intended in this instance other than as are imposed by the scope of the appended claims.

- Having now described my invention, what I claim and desire to secure by Letters Patent is:

l. The method of making in the cavity of a metal mold a casting of metal or alloy comprising casting the same while at a temperature approximately at the point of fluidity into said cavity under a pressure at least high enough to force the same to fill said cavity, and subjecting the same while cooling to an additional pressure.

2. The method of increasing the speed at which metal castings may be successively made in a metal mold of assembled units comprising progressively cooling below the point of fluidity different portions of a casting and progressively opening units of said mold juxtaposed to such cooled portions of each casting.

3. The method of making repeated castings in the cavity of a sectional mold comprising forming a mold cavity having a plurality of interconnected sections, casting metal in .such cavity, cooling a portion of said casting in advance of other portions, and holding said cooled portion of said casting in said cavity by interlocking contact between an exterior surface of the cooled portion of such casting and an adjacent side section'of the mold.

4. The method of claim 3 characterized by removing at least a section of said mold covering an area of, and while holding, said cooled portion of said casting. 4

5. A casting, having a lower surface and an upper surface, a recess located therebetween near cation has taken place and the metal is subjected the upper surface thereof, a nick located therebetween near the lower surface thereof, the distance between said nick and said upper surface being substantially the same as the distance between said recess and said lower surface.

6. A casting, having upper and lower edges, one or more ridges therebetween at a distance from said upper edge substantially equal to the distance of one or more corresponding recesses therebetween from said lower edge.

7. A plurality of castings, one or more castings with a recess therein in the upper portion thereof and with a nick therein in the lower portion thereof and one or more castings with a protuberance therein in the upper portion thereof, said protuberance engaging said recess in juxtaposed castings.

8. High castings having one or more recesses located in the upper portion thereof and one or more nicks located in the lower portion thereof and low castings having one or more recesses and one or more nicks similarly located, the distance of the recesses in the high and the low casting from the lower edge thereof being the same as the distance of a nick in the lower portion of the low casting from the upper edge of said low casting.

9. A casting for typographical purposes having a character bearing face at one end of a relatively long body, at least one or more nicks in the surface of each of two opposing sides 01. the body, and a recess in the surface of the remaining end of the'body parallel to said nicks.

10. A sectional mold having a casting forming cavity enclosed therein, and at least one protuberance from a surface of said cavity adapted to hold the casting in said cavity when a section of the mold has been moved at least partially uncovering said casting.

11. A mold having a casting forming cavity inclosed therein, and at least one protuberance upon a surface of said cavity at a point removed.

from a crucial surface of a casting to be formed in said cavity,' whereby when the casting is of metal that expands upon cooling such expansion stresses such metal intermediate its crucial surface and said at least one protuberance. i

12. A mold having a relatively long casting forming cavity therein, and at least two protuberances at spaced apart intervals upon a surface of said cavity transverse to its length.

JAMES EDWARD PARKER. I

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