. TRADITIONAL MACHINES VENTS. By positioning the parting line right on the protruding feature, you can avoid the undercutting problem. 1 to 2 degrees works very well in most situations. 523000. Figure 7. The complexity, size, and material of the mold impact tooling costs. 5. Intricate designs and multiple cavities increase tooling complexity, resulting in higher expenses. Identical processing conditionsThe core lifter system is intended to be installed in an appropriate mold, such as a plastic injection mold, and one form of a plastic injection mold is shown in FIG. The Friction Puller. We will explain it later. Double Valve - VD. Kehui Mold is a professional production and processing company in the plastic moulding industry, specializing in the industry for more than 8 years, and has accumulated a lot of practical experience. Our mini cranes are easy to maneuver into places where conventional lifting equipment just can’t do the job. . Add a 0. Increasing cooling time may also help. A Mold Lifter is a critical feature within injection molding, designed to facilitate the ejection of molded parts with complex geometries. Small batch plastic injection molding. Sometimes there are some features on B Side of surface and they create interference in mold separation (features like snaps, dog house etc), they are in internal undercut region. The first step in designing a lifter for injection molding is to analyze the part design. Necessary lifters are much more compact and damage-resistant. Touch device users can explore. . The injection mold lifter design is an integral part of injection molding processing. Moldworx has found that the industry standards range. The injection mold lifter is an essential component that makes the whole injection molding process successful. 005 deep. Min Order: 1 set. Brass inserts are small metal components that are used in plastic injection molding to create a wide variety of parts and products. To help you navigate this process, here’s a step-by-step guide for designing an injection slide mold: 1. The process is a quick, economical way to mass produce a number of parts, ranging from high-precision engineering components to cosmetic product enclosures. 002-0. The crane operator is able to complete the movement with the help of double J-hook mold beams. As the name suggests, this is one of the most carefully done parting lines in plastic design. Used primarily to form undercuts, lifters also provide ejection functionality in conjunction with other ejection systems. It is typically mounted on the moving half of the mold, and it helps to lift the mold off the stationary half of the mold during. Snap joint, AKA snap fit joint, is a common structure for connecting and fixing plastic injection molding products. The images above (Figures 1 and 2) show an example of a difficult-to-cool lifter with five molding surfaces. The lifter is a feature incorporated into the molding section of injection molding. In plastic injection molding, core separates from cavity and is drawn in tooling direction. The process involves the injection of heated, liquefied plastic into a temperature-controlled mold under high pressure. Angle pin. Bumpoffs. It utilizes a closed mold and a low-moisture low-oxygen environment. Easy-to-use. PTFE injection molding is a process used to manufacture PTFE products by injecting molten PTFE into a mold. The cop-per alloys are: • C17200, high hardness beryllium-copper alloy • C17510, high. 9375 of ejector stroke. The first step in designing a lifter for injection molding is to analyze the part design. 1 yrs CN Supplier . All molds, with the exception of prototype, to have adequate channels for temperature control. Year Established: 1998. Contact Info. molds. Plastic resin is fed into the loader in pellet form. 0 /5 · 3 reviews ·This helps to make the injection force applied to both sides balanced. The CAD files and renderings posted to this website are created, uploaded and managed by third-party community members. An efficient cooling system reduces mold cooling time, and therefore increases overall production. Small batch injection molding is a manufacturing process to production of small quantities of injection molded parts. in part geometry or tolerance that might result in poor steel conditions or require special tooling features such as lifters, slides, and threading. This post is part of our Designing for Injection Molding series. To survive in today’s competitive worldwide. 002-0. providing 0. When you partner with Fictiv, your plastics project can use handloads instead of injection molding sliders or lifters. 2. All molds should have eyebolt holes on the top side. Mold Action /. This causes a chain reaction. Injection molding is a high-precision manufacturing process that injects molten plastic into a carefully designed mold, where the plastic cools and hardens into the specified part or product. It is a variation of injection molding, which is a popular manufacturing technique for creating plastic parts. The mold is split along the parting line to allow for the injection of molten plastic and the release of the finished part. Thermal image of a hot spot in an injection mold to show where conformal cooling is required to reduce time to ejection in the cooling portion of the cycle. This formation eliminates the bending moment seen in conventional single-rod lifter. mold lifter design 【lifter material】 if main inserts use pre-harden steel,then lifter use 1. In most cases, cavities are hardened to 50-52 RC. How to avoid the Air Traps Defects. Below is a detailed injection mold lifter design guide: Step 1: Analyze the Part Design. A new approach to designing lifter cores utilizes a second guide rod that is parallel to the lifter rod. Lifter shoes can be mounted on top of or recessed into the ejector plate 9. Injection molding lifters are mechanical components that are used to lift or move specific features of a molded part during the ejection process. . The Solution: Injection Molding Handloads. The radiused dovetail design lets the core blade seat automatically at the required angle with the mold closed. The gate controls the flow of. Moreover, for the better shape, you might want to take help of rigid mold or frame. A series of plastic parts with different shapes and sizes can be processed by the coordinated change of punch, die and auxiliary forming…(Sumber : MOLD CLAMPING MECHANISM OF AN INJECTION MOLDING MACHINE, ItoSusumu,et all, 1996) Gambar 2. • In-Mould Labelling - IML. Premature gate freeze-off will reduce the available packing time in the cavity, which can increase the likelihood of sink marks. Below is a detailed injection mold lifter design guide: Step 1: Analyze the Part Design. If you need assistance, you can always contact an applications engineer to discuss your design at 877-479-3680 or customerservice@protolabs. An injection molding lifter, also known as an ejector pin or stripper pin, is a crucial component used to push or eject finished plastic parts from the mold cavity after molding. 1. The distance between the cooling channel and the ejector pins, the sleeve, the lifter (P) is 5 mm or more. Identical mold components were fabricated from the three copper alloys and steel materials. Injection molding parting line or mold split line is a line or surface on an injection molded part where the two halves of the mold meet. In particular, there is a base push territory that is needed to maintain a strategic distance from. The first step in designing a lifter for injection molding is to analyze the part design. PPS (polyphenylene sulfide) is a thermoplastic polymer that is known for its high heat resistance, chemical resistance, and dimensional stability. Thermocouples. Mold Cavities and "A" Side inserts 4. A) Mechanical injecion mold Slide Design Standards (refer to drawing S2-1 & S2-2): 1) All shut-off surfaces must have a minimum of three degrees draft in direction of slide travel. Detachable separation design, easy and fast installation, is the best choice for mold inserts and machine precision parts. Correct lifter design can improve production efficiency, ensure product quality, and reduce production problems. Plastic resin is fed into the loader in pellet form. . 2023年1月4日 / by admin. TheseInjection mold angle Lifter is the mechanism in the injection mold to release the plastic molded parts undercut and ejector the part out off mold. Collapsible cores are mechanisms that release a circular undercut feature in a method similar to a lifter. 5 degrees on all vertical faces is strongly advised. 0 piece. Molds could be a few thousand dollars or hundreds of thousands. The plastic pellets are fed into an injection molding machine, where they are melted and injected into a mold. Proper design helps ensure that good parts will be produced on the first run. Texas Injection Molding engineers work with our customers to develop and design the most robust plastic injection molded products. The mold is composed of two halves, the “A” side and “B” side. 2. Injection mold lifter scoring. Roller/Ball Bars or Die Lifters are used to lift the rubber mold and provide a roller surface to easily roll the mold in and out during the rubber mold change. Upmold is a manufacturer that specializes in the Plastic injection mold, Die casting die, Trim die, Fixture, components machining, and injection moulding parts, We service to the. Three alloys typi-cally are utilized for the mold components, which will have contact with plastic. Our lifters reduce the amount of complex machining needed to incorporate a slide, lifter or cam into the mold. 6. When you choose us, you’re getting access to an entire spread of lifters, including: Full 360° Turning Platforms. There’s also a block-like locking mechanism. This is an animation of a basic injection mold slide action. Slides or sliders are used to release any external undercuts or recesses on the outer surface of a part that may prevent it from being removed from the mold cavity. This design is the same as movable mold lifter. Add 1 degree of the draft for every inch increase in. Annual Revenue: 100000000-150000000 USD. These components have some clearance to allow for mechanical movement. Several methods are used for unscrewing molds, including hydraulic motors, splines, various gearing methods and for large multiple cavity molds, racks and pinions are used. KTM is confident that the products supplied will meet your manufacturing needs. When Injection mold opening, the lifter along the. VectorForm Lifter System features and benefits Standard Slide Base (SB. Product by brand. Locking Swiveling Wheels. Chat now. Material Considerations: The choice of materials for the mold. When there is an undercut on the inner surface of the side wall. com) that went into more detail on lifters and was a continuation of his previous post. The mold configuration should likewise incorporate clasp to inflexibly attach the numerous parts of the form. PCS Company mold components are designed and. When you choose us, you’re getting access to an entire spread of lifters, including: Full 360° Turning Platforms. The level of detail. 0. 4) Provide a . Lifters also can drag on the part and create plastic flakes. Mold Components. and the inclined surface on the ejector plate is to facilitate its reset when the mold closes. This design is the same as movable mold lifter. Plastic Injection Mold Lifter, Double Teeth Lifters $50. Continued on next page » 9 Surface Finishes INJECTION MOLDING GUIDE V2 SPI FINISH DESCRIPTION TYPICAL APPLICATIONS ADDED EXPENSE A-1 Grade #3, 6000 Grit Diamond Buff High polish parts $$$$$ In an ideal world, your moldmaker would use only KO pins in your plastic injection mold. are finished to some degree, but the more polishing required, the higher the cost of the mold tooling and the longer it will take to complete the mold. Learn more about Injection Mold Lifter Design. It is a semi-crystalline material with excellent mechanical properties and is often reinforced with glass or carbon fibers to increase its strength and stiffness. 3d Printing. The lifter also needs to be cooled when it is big and with a large contact surface with the product. An injection mold, also known as a die or injection mold tooling, is the single most expensive item built specifically to produce a plastic part. Depending on the type of molding material, you might use a gate depth that is 50-80% of the part’s wall thickness, and depending on the flow length, the width of the gate being two to six times its depth. A surface micro-/nano-structured metal plate can be joined with an injection molded plastic piece in a mold, which has been named injection molded direct joining (IMDJ). Handloads are inserts that are manually placed, or hand-loaded, into the mold to achieve features such as undercuts. This detail shows a lifter at 10 degress with 2. Smooth performance is attained due to the U-C. When the temperature rises above the melting point, the liquidity of melt will become obvious. The injection molding process by design should give perfect molded products. When the necessary push territory and edge of the ejectors are known, distinctive ejector frameworks plans can be created. Injection Molding Lifter; Injection Molding Cavity VS Core; Contact Info. However, rather than using an angled pin to control the action’s movement, lifters are driven by the action of the injection molding press pushing against the ejector plates. These allow the actions to collapse inward, providing clearance for part ejection. Our goal at KTM is to offer our clients superior service and high-quality parts with on time. Cold runner injection molding is a manufacturing process that involves injecting molten plastic into a mold to create a part or product. The student will learn in detail ejection system, injection system, cooling system, venting, gates and graining. . These inserts are typically made from brass, a strong and durable metal that is resistant to corrosion and wear. CUMSA is a family company dedicated to the design, manufacturing and distribution of innovative standard mold components and solutions for the moldmaking and molding industries. VectorForm Lifter Systems offer three types of slide bases to meet the needs of your applications. The major contribution for the lifters scoring was the load of the molded part itself. POROUS MOLD MATERIALS. 1. In plastic injection molding, core separates from cavity and is drawn in tooling direction. Double Valve - VD. Engaged in mold production, manufacturing, and processing for five years, exported to. Another conventional injection molding die for valve lifters is shown in a cross section in FIG. When venting stationary inserts or core pins in rib or part details with venting issues, I recommend no more than 0. Design bosses with an outer diameter equal 2x the nominal diameter of the screw or insert. Keep your most valuable assets, your employees and materials safe by using DME lifting hardware. This option requires considerable mold space and may result in selecting a lifting core with a smaller platen size at the expense of a larger die height. Without lifters, the pins bring out the plastic product. Plastic injection mold lifter design is a combination of the ejection mechanism and the side-core pulling mechanism appalling in the plastic injection mold. Progressive's UniLifters® System is the most widely used, standard product for molding and releasing undercuts. Fixed mould lifter structure -2. So how do the mold design engineers of pintejin molding solve this problem? 1. Using modern CAD software products, designers usually design Cavity-Lifter Injection Mold. 5 Axis CNC Machine for high precision plastic mold manufacturing. Mobile: +86 135 30801277. Once we’ve decided on the best parting line, there may be part design modifications required to allow for proper draft and surface finish to make the mold functions properly. The product drawn is co. We stand behind these products and are confident they are the highest quality in the industry. KTM was established in Ontario, Canada in 1985, with over 35 years of experience. 1) All mechanical slide design standards relative. 2) Two angle pins will be required on any slide design that exceeds seven inches in. Production. Tooling Costs. An Injection Molding Sprue refers to the channel through which molten material is introduced into a mold. Engaged in mold production, manufacturing and processing for five years, exported to major countries around the world. These are used to create under cuts in plastic parts. Plastic snap fit joint design. Thermocouples. PTFE has a very low melting point and is difficult to mold, which makes the injection molding process. by crane operator) Anti-collision sensors will stop the unit. The part’s design should be optimized for the die-casting process, considering the material’s properties, the shape of the part, and other factors. But by following a few simple rules, even the most difficult of these challenges can be overcome (parenting aside). It plays a guiding role when the front and rear molds are closed; its role is to guide. 5. A slide base, as opposed to a static base, in the ejector plate allows the lifter angle to exceed the typical maximum angle of 15° to. By gaining an in-depth understanding of the work principles and design points of lifter, you can better address the challenges in injection. With draft angles, use at least 1° on an untextured mold and a minimum of 3° with a textured mold surface. Here we'll calculate Lifter angle & Strokes. For example: arrange A company to design, B factory making mold base, C factory making core block, D factory making slider/lifter/insert etc (request every supplier control the tolerance within your requirement, so that is easy to assembly). This process offers a number of features and benefits, including cost-effectiveness, efficiency, consistency, and customization. This technique can also be used to deal with the objective creations, associated with the various shapes and sizes. On the other hand, lifters release internal undercuts and recesses as well. alloys in injection molds C17200 (A), C17510 (B) and C18000 (C) against H-13 and 420 SS. Handloads are inserts that are manually placed, or hand-loaded, into the mold to achieve features such as undercuts. Remedies: Raise the temperature of the mold or molten plastic. Whereas if you are wanting a plastic packaging container in an odd shape, you will be spending a little more. As shown below: (P value is at least 3. . Here are 15 types of side core pulling mechanisms for injection mold. There are many variables and impacts that lifters can have on your molding process and final parts. Enhancing Injection Molding Efficiency with Injection Molding Lifters. There are two situations when mold cleaning is required: (1) offline when the mold is on the bench and is cold (room temperature) and (2) online when the mold is warm and still in the press. Learn more about Injection Molding Lifter. 2 Structure of Injection Mould. Filter Valve - FV. Mold designers are able to incorporate undercuts twice as deep as previously possible using D-M-E?s new VectorForm Lifter System, designed by Takao Injection Mold Engineering (Chiba, Japan). As shown in the figure as below , the lifter is placed in the angled hole of a. 0 /5 · 12 reviews · "Nice service"1. Sprue Bushings and Runner Bars 2. The material is rotated. They have a max temperature of 250°C (482°F) and Max. 2344 for plastic injection mold; if main insert use harden up steel,then lifter need azotizing process （718H、2316H） Below is a mold lifter animation from our relative company,their website Lifters and sliders are indispensable elements in the production of injection molded parts. When it is loaded in an ejection machine for molding purposes, side A remains fixed, while side B is movable. At its most basic level, the slider is used to turn the vertical. They play a crucial role in injection molding, allowing the production of complex parts with undercuts on both the exterior and interior surfaces. A Mold Lifter is a critical feature within injection molding, designed to facilitate the ejection of molded parts with complex geometries. It is. Pinterest. Including kinds off Mold and Die Components, such as Injection Mold lifter. Plastic Injection Mold Project Manager/Focus on plastic injection filed 10 yearsAlpine mold utilizes advanced mold design and manufacturing technologies to create innovative solutions adapted to the challenges of the automotive industry. The surface of the mold cavity and sprue bush is rough. The mechanism for this mold slider is set up so that the lateral sliding positions the plastic at the best angle that allows the ejector pins to lift it up out of the mold without any problems. Injection moulding is a formative manufacturing technology, i. Mold Lifting Beams. The injected plastic melt infiltrates the micro-/nano-structure, e. Engaged in mold production, manufacturing and processing for five years, exported to major countries around the world. These specialized components help in the ejection and release of molded parts from the mold cavity, enabling manufacturers to. Here are some of the Specs:- 4 Cavities- 3 Lifters per Cavity- Slid. If you need a smaller container, or a basic plastic mold then you are looking at spending less money. For Our Paid O. 25 in. Injection-molded parts are often parts to sell as a brand new product. Molding parts/components: normally called as cavity and core, which are the closest part with plastic products. 00. The Injection Molding Lifter Mechanism is typically attached to the ejector plates with a slide and gibs. This content and associated text is in no way sponsored by or affiliated with any company, organization, or real-world good that it may purport to portray. HOME - DMECauses: Weld lines are caused by the inadequate bonding of two or more flow fronts when there is partial solidification of the molten plastic. Be aware and plan accordingly for parting lines on injection-molded parts. For Our Paid Online and offline A. Mold Action /. Lifters. unless parts of the mould are designed to move from between such overhangs when the mould opens using components called Lifters. 2. The proper solution for absolute precision positioning of press moulds during lifting operations. 001 to +0. 2023年11月22日 / 0 Comments / by Steve Yang. Moreover, whereas lifters generally offer a single axis of movement, versatile slider technology affords multiple. Here we'll calculate Lifter angle & Strokes. What is PPS Injection Molding. Generally speaking, a lifter generally consists of two parts: the body and the forming parts. 3) Maximum angle acceptable for lifter travel is 11 degrees without special design considerations. The design engineer must understand the part geometry, including any undercuts or other features that may require a lifter. Adjust the design for the flow pattern to be a single source flow. We would like to show you a description here but the site won’t allow us. The significance of well-designed Injection Mold Lifter Design cannot be overstated in the realm of Injection Mold Lifter Design. Single-Rod Lifter Systems. High Pressure - VH. Design skills for connecting lifter:. D-M-E Company introduces pre-engineered lifters with angles up to 30° and more September 2003 - D-M-E doubles undercut capability in plastic molds with the new VectorForm (TM) Lifter System. The plastic part a mold produces may be a commodity, but the mold is far from it. B) Hydraulic injecion mold Slide Design Standards. Decatur, IL 62521; Call Today 217-864-4125;. Bumpoffs. molds. An injection molding lifter, also known as a mold lift or mold lifter, is a mechanical device that is used to support and position the mold during the injection. Lifter Systems Application. Undercuts that are on the inside of a part are handled by a similar sliding mechanism called a lifter. The action, tooling, and part are cut away for reference. A wide variety of materials can be machined, including stainless steel, aluminum, magnesium, zinc, brass and much more. This comprehensive guide will explore the differences between conventional and precision injection molding, the challenges faced in this process, troubleshooting common problems, the importance of areas of precision,. B) Hydraulic injecion mold Slide Design Standards. The basic bodies are made from a high-strength and robust. Feature Depth. Watch. (i. The causes of parts sticking and sprue sticking are multifaceted, among which mold failure is one of the main reasons. There are preferences and hindrances. The parting line location on the injection mold will have an effect on how the cavity and core (both halves of the injection mold) come together and seal. In this series of lectures, you will learn the easiest explanation of injection mold design calculations, this lecture will help you to understand how to des. A single cavity test mold for a 50-mm polypropylene closure was obtained and optimized to run at the lowest cycle time possible. High Pressure - VH. In cases where the solution cannot be achieved on press, you can consider using air blow-off until the problem can be fixed. 3. Because of temperature differences, the cleaning solvents may have different degrees of. Our mini cranes are easy to maneuver into places where conventional lifting equipment just can’t do the job. The lifter structure shown in the figure below can be used. However, most injection molded parts are just not that simple. . Cooling channels are typically drilled through the mold cavity and core. Mold Cores, Core Pins and Chill Plates 3. Injection mold lifters are essential components in the field of injection molding, serving a critical role in the ejection phase of the process. Injection mold angle lifter is the mechanism in the injection mold to release the plastic molded parts undercut and ejector the part out off mold. 5 axis CNC machine is used in modern industry for not only reducing the production cost, but also it saves time and increase the profit and accuracy of the job. Injection moulding (U. Web: Injection Molding Short is a manufacturing process that involves injecting molten material, typically plastic, into a mold cavity. The most common guide device is the guidepin and guide sleeve. Product ejection is the last step in the plastic injection molding process. . The CAD files and renderings posted to this website are created, uploaded and managed by third-party community members. This post is part of our Designing for Injection Molding series. And a core mold 5 having a core portion 5a which is a cylindrical convex portion loosely inserted in the cavity. . Any shut-off angle less than three degrees must have written customer approval. An injection molding lifter, also known as an ejector pin or stripper pin, is a crucial component used to push or eject finished plastic parts from the mold cavity after. After a product solidifies in the mold, an effective method is needed to eject it from the mold. Quick Die Change (QDC) From PFA's unique portable Mechanical Die Lifters and spring loaded lifters to high force hydraulic clamping and lifting systems, you'll find the items to build a system to meet your needs at a price you can afford. Injection moulding can be performed with a host of materials mainly including metals (for which the process is called die-casting ), glasses, elastomers, confections, and most commonly thermoplastic and. The ejection system alone has several considerations. With an extensive product selection supported with superior customer service, you can count on PCS to meet your needs. The reasons and corresponding solutions are described as follows: 1. Written by: Ben MacDonald, Senior Applications Engineer. Some manufacturers of molds also engage in the manufacture of parts. • Hot Runner and Cold Runner. Ideal for plastic injection producers and aluminium foundries. • nsert Molding – Plastics over Metal and Plastics over Plastics. 8159 Injection Mold Lifter product, with strict quality control 48 HRC Injection Mold Lifter factories, producing high quality 48 HRC Injection Mold Lifter products. 3 degrees is required for light texture (PM-T1). Without it, the process would become more difficult and time. Min Order: 1. One of our expert trainers will lead the course and encourage live participant interaction without the need to travel. The lifter structure shown in the figure below can be used. The gate as large as possible, and the mold wall at right angles but not more than the wall thickness of the product, the sprue as short as possible. Why is that? Because the lifter is used at the final stage of producing plastics. Multiply the desired depth by the desired width and you get the flow area in square inches. Collapsible Core. Sometimes there are some features on B Side of surface and they create interference in mold separation (features like snaps, dog house etc), they are in internal undercut region. In conclusion, quick turn injection molding is a manufacturing process that involves the rapid production of small quantities of injection molded parts. Introduction. The plastic is melted in the injection molding machine and then injected into the mold, where it. We offer the most complete range of die clamping and handling systems in the industry for applications with mechanical presses, hydraulic presses, forging presses, injection molding machines, and die-cast machines. In most cases, the lifter rod or shank will be shortened by 0. 15 yrs CN Supplier . When designing mold cores for undercuts and side-action molding, the designer has several lifter system options. The Lifter System shown is made of standard components to simplify mold design and construction. Learn more. S-7 can also be used for slides or lifters and hardened to 54-56 RC. A Comprehensive Guide to Injection Molding Gates: Types, Functions, and Design Considerations. Second-stage pressure, mold temperature, cooling time, melt temperature, and possibly a fast injection speed. . At DME safety come first. M. Collapsible Core. Our company is molding&engineering company, provide Custom CNC Machining service to our customers. We fabricate molds as per the most requested models hence as custom parts for exceptional applications. During hot runner injection molding process, the hot runner plate needs to be heated, so the area around the hot runner gate needs to be cooled. We’re going to look into each one of these components and explain how they work and why we chose them. The best quality products are for you to choose from. DME P-Pins & More. What is a lifter in mold design? #molddesign #injectionmold A lifter is a mechanism used in the design and manufacturing of molds, typically in plastic injection molds or die-casting molds. As shown in the figure as below , the lifter is placed in the angled hole of a fixed mold plate. This design eliminates the. The blue component is the finished plastic part (cut-aw. Designing for plastic injection molding is like raising teenagers—some parts (and some teens) are more challenging than others. These movements operate better when riding on an inserted bearing surface material. They are an essential part of the injection molding process, allowing manufacturers to create complex parts with undercuts, threads, and other intricate features. Two streams of resin are injected into the mold simultaneously, along with a catalyst (such as molybdenum or tungsten) to set off the proper chemical. 8. A lifter is a component that moves on an angle with the ejection to release an undercut on a part. A short, yet informative, description of slide design and other issues can be found in section 12. 1. 25K views 1 year ago. Wherever feasible, all details should be marked with steel type and Rockwell hardness approximately .