Patent Application
20190032289
No cross reference is made at this time.
The present disclosure relates generally to construction tools and, more specifically, to hand tools for edging unset concrete.
Modern construction techniques depend heavily on concrete. Concrete is typically a composite material including cement that chemically reacts with water to harden and an aggregate, such as gravel like material. Typically, after the concrete has been mixed, the resulting slurry is poured into a form that defines the final position and shape of the concrete. Often, that form includes rebar or other metal meshes that further reinforce the concrete. In many cases, for example when pouring slabs, a top surface of the form is left exposed, and the concrete pools within the form at a desired depth. In some cases, once the wet concrete is poured, the concrete may be consolidated, for example, by agitating the concrete slurry with vibrations or rollers to drive entrapped air from the concrete and increased density. In some cases, the surface of the concrete may be subject to a finishing process, for example, as is typically used when pouring concrete floors and pavements. This may include screeding the surface of the unset concrete (to render the surface level) and pushing flat blades over the concrete surface (e.g. a bull float) to compact and smooth the surface. Subsequently, the finished concrete may be allowed to cure, transitioning from a plastic, unset state to a rigid, hardened set state.
The following is a non-exhaustive listing of some aspects of the present techniques. These and other aspects are described in the following disclosure.
Some aspects include a concrete edger hand-tool, including: a referencing structure comprising: a first member having a first surface oriented to face downward and bias a top-surface of a concrete form; and a second member having a second surface oriented to face substantially orthogonal to the first surface and bias a substantially vertical-side of the concrete form, wherein the referencing structure is configured to translate along a corner of the concrete form responsive to a force applied by a user edging unset concrete; and a concrete-surfacing structure coupled to the referencing structure, the concrete-surfacing structure comprising: a third member extending substantially orthogonal to the second member in a different direction from the first member, wherein the third member has a third surface configured to slide over and displace unset concrete to a depth defined by the top-surface of the concrete form.
Some aspects include a process, including: receiving a downward force applied by a user with a handle; transferring the force through a concrete edger and biasing the concrete edger against a top surface of a form adjacent unset concrete; biasing the concrete edger against a side surface of the form; receiving a horizontal force orthogonal to the downward force and parallel to both the top surface of the form and the side surface of the form; and concurrently translating along a corner of the form and displacing unset concrete downward to a depth defined by the top surface of the form.
The above-mentioned aspects and other aspects of the present techniques will be better understood when the present application is read in view of the following figures in which like numbers indicate similar or identical elements:
While the present techniques are susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. The drawings may not be to scale. It should be understood, however, that the drawings and detailed description thereto are not intended to limit the present techniques to the particular form disclosed, but to the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present techniques as defined by the appended claims.
To mitigate the problems described herein, the inventors had to both invent solutions and, in some cases just as importantly, recognize problems overlooked (or not yet foreseen) by others in the field of construction tool design. Indeed, the inventors wish to emphasize the difficulty of recognizing those problems that are nascent and will become much more apparent in the future should trends in industry continue as the inventors expect. Further, because multiple problems are addressed, it should be understood that some embodiments are problem-specific, and not all embodiments address every problem with traditional systems described herein or provide every benefit described herein. That said, improvements that solve various permutations of these problems are described below.
Existing tools for finishing unset concrete, i.e., before the concrete has hardened, suffer from certain deficiencies. Many tools are not well-suited for floating or otherwise finishing the surface of concrete near the edges of a form, which often can involve relatively confined, difficult-to-reach spaces, for example, in corners, and are often difficult to reach with other finishing tools designed to finish the surface of concrete in larger areas away from the edge.
Tools referred to as “edgers” exist for finishing closer to the edge of a form, but many of those tools leave the surface of the concrete with a relatively imprecise contour, often dipping in some areas and rising in others, leaving waves in the surface of the concrete. In many cases, these waves arise from the user's hand rising and falling while sweeping along an edge of a slab. These resulting contours in the hardened the concrete are often visually unappealing and can leave undesirable gaps or consume excessive amounts of building tolerances when interfaced with subsequent structures. Further, many existing concrete edging tools are not well-suited to impart desirable properties in the corners of concrete. Often, it is desirable to vary the density of aggregate to cement near the corner relative to the bulk body of a concrete slab. Corners often exhibit superior properties, for example, resistance to chipping and cracking, when the cement near the corner has a higher density in the concrete relative to the bulk of the slab. Such properties may be modified by mechanically working the concrete in an unset condition near the surface to drive aggregate away from the surface, but many existing edging tools merely drive the aggregate downward, and not inward from sides of a slab or other concrete body.
As described below, in some embodiments, the concrete edger hand-tool 10 may be configured to interface a referencing structure 12 with a concrete form that defines a orientation and elevation of a concrete surfacing structure 14. In some embodiments, the concrete edger hand-tool 10 may be slid or otherwise translated along the edge of the form, along an axis of movement 16, maintaining contact between the form and the referencing structure 12, while the concrete surfacing structure 14 displaces the surface of unset concrete to a uniform, substantially planar depth relative to a top surface of the form, as described in greater detail below. Further, in some cases, the referencing structure may clear debris from the top of the form in advance of its path, providing a level surface upon which the translate.
The tool 10 is referred to as a hand-tool, but this term is also consistent with robotically operated implements, e.g., having a mechanical interface to attach to a robotic arm or track having, e.g., three to six degrees of freedom. Tool 10 is referred to as a concrete edger, but the tool may be used to edge other materials, including plaster of Paris, Portland cement, clay, and other materials that transition from an unset state to a set state. Tool 10, further, may be used in regions of concrete (or other material being surfaced) other than edges, e.g., along joints for thermal expansion, or to impart patterns in the surface.
In some embodiments, the referencing structure 12 may have a generally inverted L-shaped formed by a horizontal member 18 and a vertical member 20. In some embodiments, the horizontal member 18 may intersect with the vertical member 20 at a corner 22 where a bottom surface 24 of the horizontal member 18 meets a vertical surface 26 of the vertical member 20. In some embodiments, the corner 22 may have a generally right angle. Or in some cases, this angle may be adjustable, e.g., with a hinged corner and curved slot through adjacent plates normal to axis 16 through which a bolt may be tightened when the hinge is at a desired angle. In some embodiments, the corner 22 may have a radius of curvature that is less than 5 mm, for example, less than 2 mm, and in some cases less than 1 mm, such that the surfaces 24 and 26 may both contact a top and a side of a form (for unset concrete) concurrently and uniformly (though embodiments are also consistent with other shapes, which is not to suggest that any other description is limiting). In some embodiments, the bottom surface 24 and the side surface 26 are planar surfaces that are orthogonal to one another.
Geometric attributes described herein should be interpreted as being within 10% variation of the attribute described, unless otherwise indicated, and that geometric attributes described as being substantially in accordance with an attribute should be interpreted as being within 20% variation of the attribute described. Planar services may be characterized as being within less than 5 mm variation according to a root mean square deviation from a best fit reference plane, and substantially planar surfaces may be characterized as being within 1 cm of this metric. In another example, orthogonal services may be within 10% of 90 degrees angles of one another, and substantially orthogonal surfaces may be within 20% of 90 degrees. Similarly, co-planar surfaces may be interpreted as being within less than 5 mm of being coplanar and have normal vectors within 15 degrees of one another, and substantially coplanar services may be interpreted as being within less than 10 mm of being co-planar and have normal vectors within 30 degrees of one another. Coordinate systems, and references to up, down, top, bottom, vertical, and horizontal, and the like should be read with respect to gravity when the tool 10 is positioned for use while edging unset concrete.
In some embodiments, the members 18 and 20 may have the same or substantially the same thickness between surfaces 24 and 26 and outer surfaces 28 and 30. Examples of dimensions of the concrete edger hand-tool 10 are shown in detail with respect to
In some embodiments, the concrete edger hand-tool 10 may have a referencing structure 12 that defines scraping edges 32 and 34, in some cases on both ends along axis 16 of the reference structure 12, that is at end 36 and end 38. Scraping edges, in some cases, may have a 90 or smaller degree angle of attack with respect to a vectored normal to the surface 28 (e.g., a 45 degree chamfer, or 20 degree or smaller chamfer), to form a relatively sharp knife edge that terminates at surface 24. Similarly, scraping edges on the member 20 may have these attributes too, to form a relatively sharp knife edge that intersects the surface 26 and scrapes the side of a form clean. In some embodiments, the ends 36 and 38 of the referencing structure may be characterized as being chamfered when viewed from above, in a plan view. Or in some embodiments, these ends may be curved to protect the user from cutting surfaces.
In some embodiments, the referencing structure 12 may define a relatively uniform cross-sectional volume 40 along the axis of movement 16, such as a rectangular prism bounded on two sides by surface 24 and by surface 26. In the illustrated embodiment, the surfaces 24 and 26 are generally smooth and continuous between the ends 36 and 38. In other embodiments, the surfaces 26 and 24 may be discontinuous along axis 16 while being substantially continuous orthogonal to axis 16. For example, a pair of orthogonal cylindrical rods forming an inverted L-shaped may be disposed at each of the ends 36 and 38, with the 2 rods on each end extending generally orthogonal to axis 16. In another example, the member 18 may be bent downward so that a distal edge of the member 18 rides on a top surface of a form. Or in some embodiments, a distal end of member 18 may be bent downward so that the referencing structure 12 envelops a top surface of a form and slides against an inner side of the form, a top side of the form, and an outer side of the form.
The illustrated referencing structure 12 may be manufactured with a variety of different techniques. In some embodiments, the referencing structure 12 may be made from a monolithic body of material, for example, extruded aluminum angle bracket or cast angle iron (e.g., stainless steel or galvanized steel). In some embodiments, the referencing structure 12 may be manufactured by bending sheet-metal, for example, to a 90 degree corner having a radius of less than 5 mm at an inner corner, for instance, less than 3 mm or less than 2 mm. In some embodiments, distal corners of the referencing structure at ends 36 and 38 may be chamfered to protect users from sharp corners.
In some embodiments, various handles like those described below may be attached to a top surface 28 of the referencing structure 12. In some embodiments, the handles may be positioned such that a downward force applied by the handle is centered over the referencing structure 12, on a side of member 20 in which the referencing structure 12 is disposed. In other embodiments, the referencing structure 12 may be cast or formed from composite materials like Kevlar™, carbon fiber, or fiberglass. In some embodiments, the referencing structure 12 may be formed with an injection molding process, for instance, with injection molded nylon or PVC.
The concrete surfacing structure 14 may cantilever or otherwise extend from the referencing structure 12 in a direction orthogonal to the axis of movement 16 to a distal end 42. In some embodiments, the concrete surfacing structure 14 may include a bottom surface 44 and scoops 46 and 48 along edges 36 and 38, on either side of a concrete displacement plane 50. In some embodiments, the scoops 46 and 48 may merge back into the top surface 28 of the referencing structure 12 with curves 52 at either ends 36 and 38, which may be compound or linear curves. In some embodiments, curves 52 may vary, for example monotonically, for example linearly in the radius of curvature or in their axis of curvature elevation along the axis 16. Scoops 46 an 48 may further impart mechanical strength the concrete surfacing structure 14, by carrying compressive loads produced as concrete is forced downward, and preventing the concrete surfacing structure 14 from flexing upward in response.
In some embodiments, scoops 46 and 48 may each define generally triangular prism volumes 54 on either side 36 and 38 of the tool 10. In some embodiments, these volumes may terminate at the concrete displacement plane 50, which may be coplanar with the surface 24 of the referencing structure, such that the concrete may be displaced to an equal elevation to a top surface of the form when the referencing structure 12 is slid along the form. Or, in some cases, a height or angle (or both) of the concrete surfacing structure 14 may be adjustable relative to the referencing structure 12, e.g., with threaded couplings on each end 36 and 38 that can be adjusted to slide one along the other. Or these two components 12 and 14 may be offset or angled by a fixed amount set when the tool 10 is manufactured.
The illustrated scoops 46 and 48 have generally linear slopes at a relatively consistent angle along the axis 16, but embodiments are also consistent with other shapes, for example, curved scoops 46 and 48 that curve about an axis orthogonal to axis 16, for instance, curving upward or downward in a direction of movement along axis 16. In some embodiments, the curvature may be concave or convex. In some embodiments, the concrete surfacing structure 14 may have a generally uniform cross-sectional shape along a first portion 56 and then a varying cross-sectional shape along a second portion 58 orthogonal to the axis of movement 16. Or in some embodiments, the shape may change along an entire length of the concrete surfacing structure 14.
In the illustrated embodiment, the concrete displacement plane 50 is generally uniform and designed to be generally parallel to a top surface of the form, but embodiments are consistent with other shapes. In some embodiments, the concrete surfacing portion 14 may angle upward or downward in the direction of movement or perpendicular to the direction of movement away from the referencing structure 12, depending upon the desired shape to be imparted upon unset concrete. In some embodiments, the width of the concrete displacement plane 50 along axis 16 may be reduced, for example, to a point (producing a “v” shape, or “u” shape) or may be broadened beyond that shown, which is not to suggest that other dimensions may not be varied.
In some embodiments, the scoops 46 and 48 may be integrally formed with the rest of the concrete surfacing structure 14, including a central member 60, the bottom portion of which may be the concrete displacement surface 50. In some embodiments, the scoops 46 and 48 may be integrally formed by bending a body of sheet-metal, by injection molding, by application of up of composite materials to a form, or the like (e.g., using any of the techniques described above with reference to the structure 12). In some embodiments, the scoops 46 and 48 may be welded to the central member 60. Or in some embodiments, the scoops 46 and 48 may be removably attached to the central member 60, for example, such that different scoops may be applied, for example, with bolts. In some embodiments, the concrete surfacing structure 14 and the referencing structure 12 are integrally formed as a single monolithic tool 10, for example, with the above-described injection molding, composite layup, casting and machining, or sheet-metal bending techniques. Or in some embodiments, the concrete surfacing structure 14 may be formed from sheet-metal that is welded (or glued, or bolted, or riveted) to a bent angle bracket.
In operation, the tool 10 may be deployed after unset concrete is poured into a form 74, and in some cases, after screeding the unset concrete. In some embodiments, the form may be a temporary form, such as wooden two-by-sixes or two-by-eights enveloping a region in which a slab is being poured. In some embodiments, the form may be or include a permanent structure adjacent the concrete being poured, for example, previously poured and set concrete.
In some embodiments, after concrete is poured into an interior region 76 of the form 74, the tool 10 may be aligned to the form 74. For example, the referencing structure 12 may be biased against the form 74, with the concrete surfacing structure 14 disposed in an interior region 76, over or contacting unset concrete. In doing so, a user may press downward on the handle 70, and in some cases apply a torque to the handle 70 about axis 16 that biases surface 26 of the referencing structure 12 against vertical side 80 of the form 74, while the downward force 70 biases surface 24 of the referencing structure 12 against a top surface 78 of the form 74. At the same time, the user may apply a force parallel to axis 16 that causes the referencing structure 12 to slide along the form 76, while remaining biased in the manner described above, such that the referencing structure 12 remains aligned to the form 74 and has a single degree of movement along axis 16 relative to form 74, at least until the above-described biasing forces are overcome or removed, for example, when the tool 10 is lifted off of the form 74. In some embodiments, a user may sweep the tool 10 along the corner 82, holding the tool 10 in alignment with the corner 82 to apply forces to, and displace, unset concrete within region 76 of form 74, along an edge of recently poured concrete.
As the tool 10 translates, for example slides (or consistent with embodiments described below, rolls) along axis of movement 16, unset concrete may encounter a leading scoop, in the depicted case scoop 48. Elevated portions of the unset concrete, e.g., due to clumping, may encounter the scoop 48, which may gradually press and smooth out and downward the unset clumped concrete, in some cases, causing clumps to spread sideways, and in other cases causing clumps to spread downward, thereby smoothing an edge of the unset concrete. The central portion member 60 may then maintain a displacement of the concrete at a given point as the tool slides over that concrete, in some cases, shearing the top surface of the concrete and displacing the concrete to a depth that matches that of the top surface 78 of the form 74, in a planar orientation that is coplanar with (or not coplanar with, but parallel to) the top surface 78 of the form 74.
In some embodiments, the tool 70 may be swept back and forth, in opposing directions along axis 16 to repeatedly work the concrete and adjust the surface. Adjusting the surface may include repeated shearing and displacement of the surface of concrete to smooth out clumps. As the tool 10 swings in the opposite direction, scoop 46 may instead perform the operations described above with reference to scoop 48. In some embodiments, mechanically working the surface of the concrete along the edge may modify the relative density of aggregate in the surface of the concrete, for example, driving aggregate downward and away from the form 74, such that the surface of the concrete has a higher percentage of cement and presents a smoother, more aesthetically appealing, and in some cases stronger surface with fewer boundaries between aggregate and cement at which cracks can originate. These forces may also drive entrapped air from the concrete, increasing density near the surface. Similarly, transition region 66, described above may mechanically displaced concrete that is unset along a corner of a pool of the concrete within the form 74 both downward and inward, along at least part of the depth of the transition region 66, for instance, a lower portion of the transition region 66, such that both a top surface, and a side surface of a corner of the concrete undergo the change in relative density of cement and aggregate described above, thereby imparting the above-described desirable characteristics both to the top surface and side of the corner of concrete. Upon finishing working an edge, in some cases, the tool may be moved to another portion of the form 74, to be swept along that portion, in some cases edging an entire perimeter of a slab of onset concrete, before the concrete has time to cure and harden. After a given edge has been processed, in some cases, the tool 10 may be lifted vertically and cleaned. In some cases, the tool 10 may be made from a resilient material, such as steel or plastic, that when struck against a rigid structure, vibrates and causes residual hardened concrete to be shed from the tool 10.
In some embodiments, as the tool 10 slides along the top surface 78 of the form 74, a leading or trailing edge of the referencing structure 12 may clean debris, such as previously spilled and hardened concrete or other construction materials, from a top surface 78 of the form 74, similar to a planer used in woodworking, thereby providing a more uniform reference for the tool 10 to mechanically orient the concrete surfacing structure 14. (Indeed, some embodiments may include a woodworking planer blade, e.g., disposed facing downward from or inward from the surfaces of the referencing structure.) Otherwise, in some cases, debris may cause the referencing structure 12 to pivot, as the referencing structure 12 slides over the debris, which may impart a movement of the concrete surfacing structure 14 other than translation along axis 16, and may cause the concrete to have an uneven surface. That said, embodiments are also consistent with tools 10 that do not scrape the top surface 78 of the form 74, which is not to suggest that any other description is limiting.
In some embodiments, the referencing structure 112 may include leading and trailing blades 118 and 120 that may scrape debris from the top of a form as the tool 100 is slid along the form in the manner described above. In some embodiments, the blades 118 and 120 may be sharpened with, for example, a knife sharpening block. In some embodiments, the body of the tool 100 may be formed by casting steel or aluminum and machining the resulting casting, or embodiments may be machined from, e.g., a 10 or 20 mm sheet of steel or aluminum. The handle 116 may include a base 122 and a handle receptacle 124, which may receive, for example, a wooden pole or fiberglass pole (e.g., longer than 50 centimeters, or longer than 1 meter) that inserts into a circular opening of receptacle 124 and is attached to the receptacle 124, for example, with adhesive, screws, or rivets. In some embodiments, the handle receptacle 124 may be configured to pivot about an axis 126, in some cases freely, as the tool is slid from left to right and the angle of the tool changes position relative to the user, or in some cases with a fixed angle, that may be adjustable, for example, by adjusting a threaded coupling about which the receptacle 124 pivots relative to the rest of the tool 100.
The reader should appreciate that the present application describes several independently useful techniques. Rather than separating those techniques into multiple isolated patent applications, applicants have grouped these techniques into a single document because their related subject matter lends itself to economies in the application process. But the distinct advantages and aspects of such techniques should not be conflated. In some cases, embodiments address all of the deficiencies noted herein, but it should be understood that the techniques are independently useful, and some embodiments address only a subset of such problems or offer other, unmentioned benefits that will be apparent to those of skill in the art reviewing the present disclosure. Due to costs constraints, some techniques disclosed herein may not be presently claimed and may be claimed in later filings, such as continuation applications or by amending the present claims. Similarly, due to space constraints, neither the Abstract nor the Summary of the Invention sections of the present document should be taken as containing a comprehensive listing of all such techniques or all aspects of such techniques.
It should be understood that the description and the drawings are not intended to limit the present techniques to the particular form disclosed, but to the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present techniques as defined by the appended claims. Further modifications and alternative embodiments of various aspects of the techniques will be apparent to those skilled in the art in view of this description. Accordingly, this description and the drawings are to be construed as illustrative only and are for the purpose of teaching those skilled in the art the general manner of carrying out the present techniques. It is to be understood that the forms of the present techniques shown and described herein are to be taken as examples of embodiments. Elements and materials may be substituted for those illustrated and described herein, parts and processes may be reversed or omitted, and certain features of the present techniques may be utilized independently, all as would be apparent to one skilled in the art after having the benefit of this description of the present techniques. Changes may be made in the elements described herein without departing from the spirit and scope of the present techniques as described in the following claims. Headings used herein are for organizational purposes only and are not meant to be used to limit the scope of the description.
As used throughout this application, the word “may” is used in a permissive sense (i.e., meaning having the potential to), rather than the mandatory sense (i.e., meaning must). The words “include”, “including”, and “includes” and the like mean including, but not limited to. As used throughout this application, the singular forms “a,” “an,” and “the” include plural referents unless the content explicitly indicates otherwise. Thus, for example, reference to “an element” or “a element” includes a combination of two or more elements, notwithstanding use of other terms and phrases for one or more elements, such as “one or more.” The term “or” is, unless indicated otherwise, non-exclusive, i.e., encompassing both “and” and “or.” Terms describing conditional relationships, e.g., “in response to X, Y,” “upon X, Y,”, “if X, Y,” “when X, Y,” and the like, encompass causal relationships in which the antecedent is a necessary causal condition, the antecedent is a sufficient causal condition, or the antecedent is a contributory causal condition of the consequent, e.g., “state X occurs upon condition Y obtaining” is generic to “X occurs solely upon Y” and “X occurs upon Y and Z.” Such conditional relationships are not limited to consequences that instantly follow the antecedent obtaining, as some consequences may be delayed, and in conditional statements, antecedents are connected to their consequents, e.g., the antecedent is relevant to the likelihood of the consequent occurring. Statements in which a plurality of attributes or functions are mapped to a plurality of objects (e.g., one or more processors performing steps A, B, C, and D) encompasses both all such attributes or functions being mapped to all such objects and subsets of the attributes or functions being mapped to subsets of the attributes or functions (e.g., both all processors each performing steps A-D, and a case in which processor 1 performs step A, processor 2 performs step B and part of step C, and processor 3 performs part of step C and step D), unless otherwise indicated. Further, unless otherwise indicated, statements that one value or action is “based on” another condition or value encompass both instances in which the condition or value is the sole factor and instances in which the condition or value is one factor among a plurality of factors. Unless otherwise indicated, statements that “each” instance of some collection have some property should not be read to exclude cases where some otherwise identical or similar members of a larger collection do not have the property, i.e., each does not necessarily mean each and every. Limitations as to sequence of recited steps should not be read into the claims unless explicitly specified, e.g., with explicit language like “after performing X, performing Y,” in contrast to statements that might be improperly argued to imply sequence limitations, like “performing X on items, performing Y on the X'ed items,” used for purposes of making claims more readable rather than specifying sequence. Statements referring to “at least Z of A, B, and C,” and the like (e.g., “at least Z of A, B, or C”), refer to at least Z of the listed categories (A, B, and C) and do not require at least Z units in each category. Unless specifically stated otherwise, as apparent from the discussion, it is appreciated that throughout this specification discussions utilizing terms such as “processing,” “computing,” “calculating,” “determining” or the like refer to actions or processes of a specific apparatus, such as a special purpose computer or a similar special purpose electronic processing/computing device.
In this patent, certain U.S. patents, U.S. patent applications, or other materials (e.g., articles) have been incorporated by reference. The text of such U.S. patents, U.S. patent applications, and other materials is, however, only incorporated by reference to the extent that no conflict exists between such material and the statements and drawings set forth herein. In the event of such conflict, the text of the present document governs.
The present techniques will be better understood with reference to the following enumerated embodiments:
1. A concrete edger hand-tool, comprising: a referencing structure comprising: a first member having a first surface oriented to face downward and bias a top-surface of a concrete form; and a second member having a second surface oriented to face substantially orthogonal to the first surface and bias a substantially vertical-side of the concrete form, wherein the referencing structure is configured to translate along a corner of the concrete form responsive to a force applied by a user edging unset concrete; and a concrete-surfacing structure coupled to the referencing structure, the concrete-surfacing structure comprising: a third member extending substantially orthogonal to the second member in a different direction from the first member, wherein the third member has a third surface configured to slide over and displace unset concrete to a depth defined by the top-surface of the concrete form.
2. The hand-tool of embodiment 1, comprising: a fillet disposed between at least part of the third surface and a fourth surface, the fourth surface being opposite and parallel to the second surface on the second member, wherein the fillet is configured to slide over and displace a corner of the unset concrete downward and away from the form, wherein the third surface comprises a substantially planar region that extends substantially parallel to the first surface.
3. The hand-tool of embodiment 1, comprising: a chamfered interior corner between the third surface and the second member.
4. The hand-tool of embodiment 1, comprising: a continuous surface that includes the third surface and a fourth surface of the second member, wherein the continuous surface curves with a radius of greater than 8 millimeters to transition between substantially orthogonal planes defined by the third surface and the fourth surface respectively.
5. The hand-tool of embodiment 4, wherein: the first member and the second member join at an intersection that, on one side including the first surface and the second surface, has a radius of curvature of less than 6 millimeters; and the third member and the second member join at the intersection, the intersection having on another side including the third surface, a radius of curvature greater than 10 millimeters.
6. The hand-tool of any one of embodiments 1-5, wherein: the first surface includes a surface of a roller having an axis of rotation substantially normal to the second surface.
7. The hand-tool of any one of embodiments 1-5, wherein: the first surface includes two areas of contact of two rollers configured to roll along a top surface of the form.
8. The hand-tool of any one of embodiments 1-5, wherein: the first surface lies substantially in first plane and is configured to slide over the top surface of the form; the second surface lies substantially in a second plane orthogonal to the first plane and is configured to slide against the vertical side of the form; and the third surface lies substantially in the first plane.
9. The hand-tool of embodiment 8, comprising: a handle configured to receive a downward force from a user centered on a same side of the second plane as the first surface.
10. The hand-tool of embodiment 9, wherein: the handle extends longer than 50 centimeters and has an adjustable angle relative to the reference structure.
11. The hand-tool of any one of embodiments 1-10, wherein: the referencing structure and the concrete-surfacing structure are configured to level an edge of unset concrete to an elevation that substantially matches an elevation of the top surface of the form.
12. The hand-tool of any one of embodiments 1-11, wherein: the referencing structure is configured to constrain the cantilevered concrete-surfacing structure to a single degree of freedom of movement while edging unset concrete and biased horizontally and vertically against the form.
13. The hand-tool of any one of embodiments 1-12, wherein: the referencing structure and the concrete-surfacing structure are rigidly disposed in fixed relation to one another.
14. The hand-tool of any one of embodiments 1-13, comprising: a curved or angled surface extending from a leading or trailing edge of a substantially planar portion of the first surface, at least part of the curved or angled surface being curved or angled to have a higher elevation over unset concrete than the substantially planar portion of the third surface.
15. The hand-tool of any one of embodiments 1-14, wherein: the third member defines a concave cross section in a plane parallel to, and offset from, the second surface.
16. The hand-tool of any one of embodiments 1-15, comprising: a scraping edge configured to scrape debris from a top surface of the form.
17. The hand-tool of embodiment 1, wherein: the referencing structure is an inverted “L” shaped referencing structure; the concrete-surfacing structure is cantilevered from the referencing structure; the referencing structure and concrete-surfacing structure are connected such that the concrete-surfacing structure has zero degrees of freedom relative to the referencing structure; the concrete-surfacing structure extends more than 5 centimeters and less than 20 centimeters away from the referencing structure; the concrete-surfacing structure comprises a curved corner having a radius of curvature of between 5 and 25 millimeters, the curved corner curving about an axis of movement that is parallel to a direction in which the referencing structure is configured to translate by sliding along the concrete form; the concrete-surfacing structure comprises upward angled or curved wings on each side along the axis of movement; the concrete-surfacing structure and the referencing structure are substantially reflectively symmetric about a plane normal to the axis of movement; opposing edges along the axis of movement of the referencing structure are configured to scrape material from the concrete form; and the referencing structure, the concrete-surfacing structure, or both are made from a monolithic body of sheet metal bent into the respective shape of the referencing structure, the concrete-surfacing structure, or both.
18. A method, comprising: receiving a downward force applied by a user with a handle; transferring the force through a concrete edger and biasing the concrete edger against a top surface of a form adjacent unset concrete; biasing the concrete edger against a side surface of the form; receiving a horizontal force orthogonal to the downward force and parallel to both the top surface of the form and the side surface of the form; and concurrently translating along a corner of the form and displacing unset concrete downward to a depth defined by the top surface of the form.
19. The method of embodiment 18, wherein: concurrently displacing unset concrete downward comprises displacing a corner of the unset concrete inward by more than 5 millimeters.
20. The method of embodiment 18, wherein: concurrently displacing unset concrete downward comprises displacing between 12 and 400 square centimeters of a top surface of the unset concrete downward to a substantially uniform depth that is substantially co-planar with the top surface of the form.
