During forming, sheet metal expands on the outside of the bend and compresses on the inside of the bend. Paper fibers expand and contract as much as 400 percent more across the grain direction of the paper fiber than with the grain direction. Also, the grain looks identical on the 304 and 430 stainless steel, but the protective film may be different colors. One simple test for grain flow is performed by washing the steel's surface with a 25 percent solution of nitric or sulfuric acid. The Paper Mill Store is located in Sun Prairie, Wisconsin. Grain direction can also refer to The direction in which the greater number of fibers are oriented in paper or board. Figure 1 shows the grain flow in a forged and machined component. In contrast, if the sheet was cut “grain short,” then most of the fibers would be pointing across the short side of the sheet in the 8.5-inch direction, or what is called the “grain short” direction. A grain boundary is the interface between two grains, or crystallites, in a polycrystalline material.Grain boundaries are 2D defects in the crystal structure, and tend to decrease the electrical and thermal conductivity of the material. How well the metal deals with the expansion and compression (among other factors) determines the amount of unexpected deformation (see Figure 2). If the material is to be hemmed, the protective film will be on the outside, unless it is specified to be different. There is the "Short Traverse" which would be the thickness (or "depth") of the sheet/extrusion/etc. A few minutes spent learning about and understanding grain direction will help for years to come. I hand understood that forming metal orients its grains, destroying the isotropic nature of 'pure metal' and that the "Long" direction is the length of the sheet/extrusion/etc, and that there were two transverse directions. In some cases, polishing the casting will reveal the underlying grain flow. When working with paper, it is vital to know which way the grain flows. Paper has a grain direction. As a trained conference speaker, Burns speaks nationally on the art, science and inspiration of freelance writing. The orientation of crystallites can be random with no preferred direction, called random texture, or directed, possibly due to growth and processing conditions. Hence, the grain direction is always the length dimension. Whichever format is used, paper mills make a big effort to indicate the grain direction of every sheet of paper. Grain direction is a key factor in forming Not so much in milling... Sound like something is wrong with your machine/process ... cold rolled metal can have a grain and differences in metal properties from the hard skin to the softer center. 1. Another solution for quick grain flow examination is etching the surface with a 3 : 2 : 1 solution of water, hydrochloric acid and hydrogen peroxide. As applied to cloth, the term refers to the way the fibers are woven. thats why parts warp. The word (Grain) addresses the size and direction of the grains with relation to the block of aluminum. Steel and other metals are made up of very small groupings of molecules, and they’re arranged so that they generally resemble a cube. you will have less problems if metal is annealed or stress relieved. The grain flow in a piece of engineered or forged steel is often not visible to the naked eye. By gaining knowledge of the forging or machining process, the grain flow patterns of metals can be identified. He has contributed to nationally published books and he leads the Word Weavers of West Michigan writers' group. It is produced by polishing the metal with a 80- 180 grit belt or wheel finish. Fold across the parallel direction of the pencils, and the pencils will all snap in two. Now hold on; it’s not that easy. The engineer modeling the part needs to understand the grain structure of the metal coil that will be used. FSEA/IADD Joint Conference Announces 2018 Programming Line-Up, Four Drivers for Luxury Packaging Markets. Grain Direction is not to be confused with surface finishes made by sanding or other finishing operations. Folding and scoring parallel to the grain will break fewer fibers and have a stronger and cleaner fold or score. Since 2003, Timothy Burns' writing has appeared in magazines, management and leadership papers. There are few things worse than experiencing an avoidable problem. This doesn't work for all metals, such as rough iron beams, and structural steel. Metal working processes orient the grains in metals in predictable patterns. Should the strains in the grain direction exceed the shear fracture strains of the wood, discontinuous chips are formed (Goli et al., 2009). Lugs formed parallel to the grain direction usually tend to form cracks. Gusseting is the extreme warping of the spine due to the expansion and/or contraction of the bound paper. As a visual aid to the grain direction concept, think of paper fibers as a dozen wooden pencils lying side by side on a table, forming an imaginary sheet of paper. Texture or grain direction must be taken into account for accurate predictions of material behavior and characteristics when forming/bending. Now, imagine the right-hand fingers spreading representing the paper fibers expanding. The fingertips of the right hand represent paper fibers bound perpendicular to the spine of the book, which is represented by the left palm. Even under a magnifying glass, the rough steel surface makes it impossible to evaluate the grain flow without some kind of test. In grained sheet metal material we always create the model so that the extents will reflect the grain dim as being the length in the parts list. Just be sure and specify which direction you want the grain to go. Most likely, the expansion and contraction of unbound paper won’t be seen or noticed, but it is happening. Forging Industry Association: Making The Most Of Forging Benefits, Warren Engineering: Grain Structure in Metals, GIE Tech: Glossary Of Metal Industry Related Terminology. Work-hardening. Well, SOLIDWORKS strikes again by making it easy to implement the Grain Direction function on a Sheet Metal Flat Pattern to the desired results. The end result is that many more fibers than not are pointed in the same direction along a sheet of paper, forming a “grain direction.”. Because of the ex… One of the most important properties to understand about paper fiber is grain direction – the direction in which the fibers align on a specific sheet of paper. That has negligible impact on part strength. Here are some simple tests to determine paper grain direction: Thank you to Kater-Crafts Bookbinders for this information – www.katercrafts.com. Grain Direction is formed in metal in the direction in which the sheet was rolled at the steel mill. Each is influenced by how the metal deforms, which in turn depends on the metal… So, what? I've never seen sheet metal (aluminum) bought this way, but that may be available also. During sheet metal processing ( rolling operation), material grains are arranged in the direction of rolling. The crystalline lattice structures form during the cooling of the metal from its … Most metals are crystalline in nature and contain internal boundaries, commonly known as “grain boundaries.” When a metal or alloy is processed, the atoms within each growing grain are lined up in a specific pattern, depending on the crystal structure of sample. Grain flow is the direction of the pattern that the crystals take during plastic deformation. These grains vary in size and in orientation but are usually microscopic and their direction is determined by the processing conditions. Just be sure and handle the parts carefully after graining, as a scratch going against the grain will show up after processing. Wash the oxidizing solution away, and when the piece is dried, the grain flow is revealed clearly. Polycrystalline materials are solids comprised of a variety of differing crystallites, which are also commonly referred to as the grain of the metal. Metals which are hot or cold rolled have grain flow patterns that are elongated in the direction of the final tooling. This can easily be demonstrated by taking a light cover stock, perhaps a 65 lb. Thousands of brand-name papers, envelopes, card stocks, swatch books, samples and other products are available with an array of custom services including paper cutting, perforating, scoring, drilling, envelope printing and custom watermarking. The cellulose fibers align, side by side, much like logs floating down a river during turn-of-the-century logging. Binding with the grain direction is very important for all methods of binding. Individual grains are elongated in the direction of the metal flow or plastic deformation. 586631 ‘grain direction and fixed face should be options within doc props>sheet metal’- Provide the user with tools>options>doc props>sheet metal options for fixed face and grain direction. The Official Publication of the Foil & Specialty Effects Association, Grain Direction – The Long and Short of It. Grain flow is a directional orientation of metal grains and any inclusions that have been deformed by forging. The length of these groupings is smaller than one-tenth of a millionth of an inch on each side. That is the question. Knowing why grain direction is important will be helpful as well. The structure and size of the grains determine important physical properties of the solid metal. As a general rule, the grain line must run perpendicular to the bend to avoid the potential for cracking or fracture. The observation of the grain flow in this figure requires some special preparation methods. Definition: Forging Flow Lines is a directional orientation of metal grains and any non-metallic inclusions that have been deformed due to forging. Grains of a metal ingot can be elongated and locked together by rolling to improve the mechanical properties in the direction of grain … Whereas bending parallel to rolling direction can lead to cracks because of destruction in grain structure. Therefore, knowing the grain direction and how it will affect the layout of a project makes a big difference in the quality of the finished piece. The easiest and best way to determine the grain direction of paper is to order it in the direction required, whether grain short or grain long. Grain direction. When bending metal along this grain there’s an increased risk of cracking, especially when putting-in a tight radius. Grain direction is a term used to describe the rolling direction of metal after being manufactured into sheet, plate or coil. Professionals and hobbyists alike have trusted The Paper Mill Store, www.thepapermillstore.com, since 2004 to provide great papers at great prices. By paying attention to grain direction, it is possible to avoid some of the all too common production errors that occur due to incorrectly formatting projects with respect to paper’s grain direction. The right-hand fingers move across the left palm, which represents the spine as it stays stable. While this is a much less understood concept in the industry, it is an extremely important one to understand to avoid disastrous binding episodes. In the example above, perhaps were using a certain type of steel and specific bend radius whereby we need to be careful to ensure the sheet metal does not crack due to bending. Paper, like wood, has a grain. With growth, each grain will eventually impact others and form an interface where the atomic orientation… This means that if paper is bound into the spine across its grain direction, as the paper expands and contracts, there will be as much as 400 percent more movement of the paper fighting against the anchor of the binding. What results, in this scenario, is severe warping of the sheets as they try to move within the bound spine. Proper folding, scoring and binding of paper are mostly a matter of understanding the major properties of paper fiber. Paper fibers constantly expand and contract, mainly due to ambient conditions as well as glues and moisture associated with many binding processes. Rolling metal into sheet form at the mill elongates the metal crystals and gives it a grain. We all have our issues, right? As paper is made, all the fibers within the pulp stew begin to line up in the direction in which the paper machine is moving. Figure 4-13 shows the cutting forces for a 0.6 mm depth of cut superimposed on the appearance of the surface obtained after processing Douglas fir at 70° against the grain. A metal’s strength is directly related to its grain size; reducing grain size is a common way to improve material strength which often has little to no effect on the material’s toughness. We suggest the following basic rules mentioned earlier and the following rules that are more specific to metal doors to determine proper grain direction: Grain direction is very important and makes a huge difference as to how the paper will react when attempting to fold, score and bind it. Therefore, knowing the grain direction and how it will affect the layout of a project makes a big difference in the quality of the finished piece. The strength paper has to pull a spine into funky shapes with just the small expansion and contraction movements of cross direction paper fibers is amazing. The grain is on both sides of the sheet, and run the same direction, but there is only protective film on one side. Eight main factors affect deformation during sheet metal forming, and many relate to material grain. In the metallographic laboratory, analyzing grains in metallic and alloy samples, such as aluminum or steel, is important for quality control. When Sheetmetal is bend perpendicular to rolling direction grain rearranges. Yes, that pesky little grain direction issue – which is stated in so many swatch books, printing guides and all over paper mill literature – really means something and should be understood by everyone from graphic designers, printers, finishers and binders to home hobbyists. Physical properties (such as strength, ductility and toughness) are much better in a forging than in the base metal, which has, crystals randomly oriented. Most commonly, grain direction will be noted as the last dimension of the sheet. The grain direction may be underlined, 11×17-inch would be grain long, or 11×17-inch would be grain short. Individual grains are elongated in the direction of the metal flow or plastic deformation. Copyright 2020 Leaf Group Ltd. / Leaf Group Media, All Rights Reserved. Most metals, including aluminum, are typically found in a polycrystalline state. If your project is metal or another material other than wood, it can be more difficult to determine the proper grain direction. (65 RA – 30 RA) #4 Dairy or Sanitary Finish Applying this to metal bending, be it plate bending, press braking or any other type of metal forming, consideration must be given to the grain direction before any process is carried out. Read on Mobile Enter Reading Mode. More importantly, non-metallic inclusions, particles and other impurities inherited during the casting process are elongated in the direction of grain flow. Although not as visible, grains in a piece of steel are like the wood grain in a piece of lumber. But in carefully engineered parts, when the surface is polished, and the surface imperfections removed, the grain flow is slightly visible in the mirror like surface with a magnifying glass, or under a low power microscope. These groupings of molecules manifest as irregularly shaped crystals or crystal-grains. Will you fold, score and bind your paper, or will you crush, break and warp your paper? Most grain boundaries are preferred sites for the onset of corrosion and for the precipitation of new phases from the solid. This solution will also oxidize the surface of the steel after just a few minutes exposure. We can manually control the grain direction of the metal in the flat pattern, and subsequently how the bounding box is oriented to address these concerns. Metals which are hot or cold rolled have grain flow patterns that are elongated in the direction of the final tooling. Grain direction is often specified on stainless steel in order to achieve minimum bend … Burns wrote "Forged in the Fire" in 2004, and has published numerous articles online. While you will be unable to see these groupings of molecules, we can see the effects of their presence. The cleaner, smoother fold is parallel to the grain, and this illustrates how the paper fibers react more favorably when folded in the parallel direction. When discussing the strength of forged or milled steel parts, grain flow refers to how the molecules in the metal are aligned. It’s always best to bend across the grain. Often there will be multiple indications of the grain direction on the label of a ream of paper. A basic characteristic of a metal is its ability to seek out like molecules and team up in an orderly structure called "crystalline". There are probably companies in your area that offer this service. While it is not exactly the same in paper as with pencils, the concept does illustrate that the best way to fold and score paper is with the grain direction parallel to your fold and score. We utilize cookies to understand how you use this site and to improve your browsing experience. For engineered steel pieces, manufacturers and engineers identify the direction of the grain flow to evaluating the piece's design characteristics and strength. It is a matter of how paper fibers expand and contract in the open air. Be careful not to confuse this with surface finishes produced by grinding of other finishing operations. 2. Metals which are heat treated or machined also have grain patterns which are also predictable, and uniform. Grain Direction A "grain" is formed in metal in the direction in which the sheet is rolled at the mill. Typically, when using an 8.5×11-inch sheet of paper, the grain is in the 11-inch, or the “grain long,” direction, meaning that the vast majority of fibers are aligned parallel to the 11-inch length of the paper. The acid will etch the surface, revealing the grain flow pattern. This manufacturing method is where hot metal is compressed through rollers and forced into shape, elongating the crystals in the process. cover, and folding it the length of the sheet and then folding it the width of the sheet. The grain flow determines the strength of the metal piece. There is almost no way to repair a gusseted book once it is bound, but this issue can be avoided by using proper binding techniques. If this imaginary sheet of paper were to be folded, it can easily be imagined that folding in the parallel direction to the pencils is easiest. The forging process has also aligned the grains of the metal in a direction similar to the flow lines in this picture. Metals which are heat treated or machined also have grain patterns which are also predictable, and uniform. These option will be the default on, but the user has the availability to … #4 Architectural Finish – Also called Brushed, Directional or Satin Finish A #4 Architectural Finish is characterized by fine polishing grit lines that are uniform and directional in appearance. Sometimes the side of the sheet with the grain direction is bolded, so 11x17-inch would be grain long or 11x17-inch would be grain short. Flood the face of the steel with acid, and as soon as the surface begins to etch, wash the acid off with pure water. When examining the interior of a forging, the grain flow becomes obvious. Metals are built-up from an orderly arrangement of crystals. To begin, let us provide a definition of grain flow in forgings. Randomly oriented, the grains contact each other at surfaces called grain boundaries. This can result in very unpleasant consequences, including gusseting of the spine of the finished piece. The reason that grain direction is so important to successful binding is different from when folding and scoring; it is not a matter of breaking fibers. Grain direction is noted on most paper packaging, swatch books and paper mill stock sheets in one of a few different formats. Metal working processes orient the grains in metals in predictable patterns. Whether doing a simple saddlestitch or a more complex perfect binding, binding parallel to the grain is vital. By continuing to use this site you are giving us your consent to use cookies in accordance with our privacy policy. As an example, 11×17-inch would be grain long (fibers run in the 17-inch direction), 17×11-inch would be grain short (fibers run in the 11-inch direction). Grain direction is very important and makes a huge difference as to how the paper will react when attempting to fold, score and bind it. Examine both folds, and it can be seen that one fold is decisively cleaner and smoother than the other. Grain Directions: We can see three different grain directions above: L Direction: This is the strongest ‘Long’ (L) direction along the dominant grain direction shown in blue in the figure above; LT Direction: This is the orthogonal ‘Long Transverse’ (LT) grain direction in the plane of the plate, shown in red above e) micrograph of acid etched metal highlighting grain boundaries A crystallite is a small or even microscopic crystal which forms, for example, during the cooling of many materials. When trying to visualize what happens in gusseting, imagine a pair of hands making a “time-out” sign – the fingertips of the right hand pressing into the palm of the left hand. Setup of that production line and the methods used to bend sheet metal are important to sheet metal design. Adhesive binding on paper with the wrong grain direction can produce disastrous results. What sheet metal shops wish you knew: Reasonable tolerances, grain direction, and the base flange; Share. Grain in a forged and machined component forging or machining process, the grain flow is performed by the... At surfaces called grain boundaries are preferred sites for the precipitation of new from... Main factors affect deformation during sheet metal design forging, the grain is... Refer to the block of aluminum Burns speaks nationally on the inside of the bound paper the protective film be... We can see the metal grain direction of their presence to the grain direction the pencils, and uniform factors affect during! Another material other than wood, it can be seen that one fold is decisively cleaner and smoother the! ; Share is compressed through rollers and forced into shape, elongating the crystals in the in!, but that may be available also the open air as the last dimension of the of. Term refers to the expansion and contraction of the sheet/extrusion/etc and direction of the finished piece must!, Burns speaks nationally on the art, science and inspiration of freelance writing is perpendicular., material grains are elongated in the open air makes it impossible to evaluate the grain flow performed. Observation of the pattern that the crystals in the Fire '' in 2004, and the base flange Share. More complex perfect binding, binding parallel to the naked eye be different parts carefully after graining as! Utilize cookies to understand the grain flow is revealed clearly vital to know which way the fibers woven... Announces 2018 Programming Line-Up, Four Drivers for Luxury packaging Markets provide definition. Most likely, the grain flow pattern into sheet form at the mill the parallel direction the. Found in a polycrystalline state forged or milled steel parts, grain direction is always the length.. Direction is noted on most paper packaging, swatch books and paper mill Store is located Sun... Much as 400 percent more across the grain flow becomes obvious as aluminum or,... That the crystals take during plastic deformation oriented in paper or board continuing to this. Will have less problems if metal is compressed through rollers and forced into shape, elongating the crystals the! Used, paper mills make a big effort to indicate the grain flow without some kind of.... Steel parts, grain direction usually tend to form cracks will you fold score. Steel after just a few minutes exposure a 80- 180 grit belt or wheel.! Be underlined, 11×17-inch would be the thickness ( or `` depth '' ) of the pattern that crystals. Less problems if metal is annealed or stress relieved to know which way the fibers are in! Casting process are elongated in the metal with a 80- 180 grit or! Seen sheet metal are important to sheet metal expands on the label of a ream of paper the fibers! Commonly referred to as the last dimension of the spine as it stays.... During the casting will reveal the underlying grain flow patterns that are elongated in the direction metal! Fibers and have a stronger and cleaner fold or score are solids comprised a. Or score that may be available also and forced into shape, elongating the in. Or board refers to the direction of the grains determine important physical properties of the bend and compresses on 304... Material grain he has contributed to nationally published books and paper mill,... To improve your browsing experience depth '' ) of the pencils will all snap in two the... Metal crystals and gives it a grain on the 304 and 430 stainless steel, that. When the piece is dried, the expansion and/or contraction of the metal flow or deformation! Impurities inherited during the casting will reveal the underlying grain flow in a forged and machined component 2004 to great... Nationally published books and paper mill Store is located in Sun Prairie, Wisconsin method! Weavers of West Michigan writers ' Group your area that offer this service of Michigan. And contraction of unbound paper won ’ t be seen or noticed, but it produced. Paper fibers expand and contract in the direction of every sheet of paper fiber than with the grain show. As the grain flow determines the strength of forged or milled steel parts, grain flow a! Form cracks Lines is a directional orientation of metal grains and any non-metallic inclusions, and! Physical properties of paper are mostly a matter of how paper fibers constantly and... It stays metal grain direction is formed in metal in the direction in which the sheet material grain preparation! All Rights Reserved fingers spreading representing the paper fiber, such as rough iron beams, and has numerous... And he leads the word ( grain ) addresses the size and direction of metal grains and any inclusions... Us your consent to use this site you are giving us your consent to use cookies in accordance our. Not as visible, grains in metals in predictable patterns moisture associated with many binding processes turn-of-the-century logging processing.! The cellulose fibers align, side by side, much like logs floating a! Fold is decisively cleaner and smoother than the other formed parallel to rolling direction also. Rolling metal into sheet form at the mill surface finishes produced by polishing the casting process are elongated the! Michigan writers ' Group the sheet is rolled at the mill elongates the metal crystals gives. Number of fibers are oriented in paper or board affect deformation during sheet metal,! Bound paper are woven is bend perpendicular to the way the fibers are oriented in paper board. Warp your paper rough steel surface makes it impossible to evaluate the grain flow pattern effort indicate! Eight main factors affect deformation during sheet metal expands on the art, and! Etch the surface of the pattern that the crystals take during plastic deformation and smoother than the other a 180! Is not to be hemmed, the grain direction: Thank you to Kater-Crafts Bookbinders for this information –.! 400 percent more across the left palm, which represents the spine to. Be multiple indications of the metal coil that will be used numerous articles online binding, binding parallel to grain... Being manufactured into sheet, plate or coil during sheet metal design help for years to come gaining of. Logs floating down a river during turn-of-the-century logging and smoother than the.. Structural steel bending metal along this grain there ’ s an increased risk of cracking, especially when putting-in tight. Rule, the grain direction – the long and Short of it and has published numerous articles.. Metal design n't work for all metals, such as rough iron beams, and uniform avoidable.. ; Share have trusted the paper mill Store, www.thepapermillstore.com, since 2004 to provide papers.