How to Make Shoe Cutting Dies

How to Make Shoe Cutting Dies
Mass production of footwear requires cutting every type of shoe material. Shoe leather, fabric, foam, and reinforcing materials must all be cut into the shoe pattern shapes. While there are many new technologies for cutting shoe materials such as a laser, water jet, and CNC drag knife; the steel rule cutting die is still the most common for footwear production.
Shoe parts cutting dies
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Used to cut out shoe parts, these steel cutting dies and shoe sole cutters look just like cookie cutters. Each mould and dies is made of sharpened rule steel then coated with rust proof paint and marked with the shoe size and model number. Making a shoe requires hundreds of dies. One die for each part, for every size of a shoe. For high volume shoe production, the shoe factory may need many sets of cutting dies.
Making footwear cutting dies
The cutting die maker starts with the cut paper pattern templates of the shoe pattern. The worker will then bend the rule steel into shape using the paper pattern as a guide.
The worker uses a special bench that will help bend the metal. The bench has a foot-operated anvil that moves the tool head to make the bends. A skilled worker can make each cutting die outline in just a few minutes.
The final operations to make the shoe cutting dies include coating it with rust proof paint and a final check to make sure the cutting edge is very sharp. While there are many operations required to make shoe cuttings dies the production is fast, the materials and labor are relatively inexpensive. For small orders, a cutting die fee may be charged by the shoe factory, but usually, the cost of the cutting dies are accounted for the LOP (labor, overhead and profit) charges.
What is Tungsten Carbide Nozzle?
Cemented carbide nozzle is made of precision machinery and cemented carbide material (superhard alloy). The bending resistance is 2300n / mm and the hardness is hra90 degree. When machining cemented carbide nozzle, we achieve precision grinding and surface treatment to achieve the hole roughness of ra0.1 and the roughness of both ends of R is Ra0.025. There is a scientific radius of curvature design at the two entrances. This design ensures the smooth passage of the thread. Due to the whole material processing, there is no elevation angle on the drilling hole, and the bending and blocking phenomenon has been improved compared with ruby nozzle. Cemented carbide nozzle is made by hot pressing and sintering hot straight hole and hill hole. Because of its hardness, low density, excellent wear resistance and corrosion resistance, cemented carbide nozzle has been widely used in sand blasting and shot peening equipment, which ensures that the product can be used in the best air and abrasive for a long time.
advantages
Advantages of cemented carbide nozzle: corrosion resistance, long service life, excellent performance, high cost performance, not easy to wear.
Carbide nozzle and other nozzles: common nozzle materials include cast iron, ceramics, tungsten carbide, silicon carbide, boron carbide. Ceramic nozzles are only used in non aggressive light equipment and abrasive in explosion cabinets. Tungsten, silicon, and boron carbide are the most popular blasting applications due to their long service life. The following is a list of carbide nozzles and their comparison with other nozzles.
The shape of nozzle hole of cemented carbide determines its air flow pattern. The nozzle generally has a straight hole or a limiting hole, a hill hole.
1. Straight hole (cemented carbide nozzle 1): the straight hole nozzle forms a sealed air flow mode for on-site or internal air flow. This facilitates the realization of small tasks, such as cleaning parts, weld forming, cleaning handrails, steps, plaques, or stone carvings and other materials.
2. Traditional long hill design (carbide nozzle 2)
3. The orifice nozzle forms a sufficient airflow pattern, and the grinding speed can be increased up to 100% for a given pressure. The best choice of Venturi surface is to improve the productivity of the nozzle. Compared with the straight hole nozzle, the productivity of the long mound nozzle can be increased by 40% when the abrasive consumption is about 40%.
4. Double venturi (carbide nozzle 4): Double venturi and wide throat nozzle are the enhanced version of long venturi nozzle. The double dome style can be thought of as having two nozzles between a set of slits and holes to allow the incoming atmosphere to enter the downstream section. The outlet end is also wider than the traditional nozzle. These two modifications are made to increase the size of the airflow pattern and minimize abrasive loss at a speed.
5. Wide throat nozzle (carbide nozzle 5): wide throat nozzle is equipped with a large outlet and a large divergent outlet. When matched with the same size hose, they can increase productivity by 15% over a smaller throat nozzle. When wide throat nozzles also have large divergent holes, they can use a lower abrasive mode under higher pressure, and the yield can be as high as 60%.
For some lattice bridges, the back of the flange, the inside of the pipe type of shrink point, can effectively use angled nozzles. Many operators spend a lot of time and abrasive to wait for a bounce to complete the job. The use of angle nozzle as long as hair less time is always able to repair quickly, reducing the overall time.
Application
Cemented carbide has a series of excellent properties, such as high hardness, wear resistance, good strength and toughness, heat resistance and corrosion resistance. Especially, its high hardness and wear resistance remain unchanged even at 500 ℃ and high hardness at 1000 ℃. Cemented carbide is widely used as tool material, such as turning tool, milling cutter, planer, drill bit, boring tool, etc. it is used to cut cast iron, non-ferrous metal, plastic, chemical fiber, graphite, glass, stone and ordinary steel, as well as refractory materials such as heat-resistant steel, stainless steel, high manganese steel and tool steel.
Cemented carbide nozzles offer the advantages of economy and longer service life when it is unavoidable to rough load and unload and media used to cut abrasives (glass beads, steel balls, steel sand, minerals or cinders). Traditionally, cemented carbide is the preferred material for cemented carbide nozzle.
Cemented carbide nozzle is widely used in surface treatment, sandblasting, spray painting, electronic, chemical process and other industries.
Cemented carbide nozzles are also used in different applications, such as for wire straightening, wire guides and other aspects.
WHEN TO USE A CONCRETE SCARIFIER
A Concrete Scarifier is one of the most productive pieces of surface prep equipment for heavy removal jobs and to prep for overlay. Some people find it difficult to identify when using a scarifier is a better option over another piece of equipment such as a grinder or shot blaster. It is important to remember that there isn’t necessarily one piece of surface prep equipment that is better than others, each machine has its benefits and will work better in certain situations. Understanding when different machines are most effective will ensure maximum efficiency and optimum results.
In this blog, we highlight a few of the situations where a scarifier would be the most effective option. Obviously, the use of a scarifier is not limited to the following situations.
TRIP HAZARDS
Trip hazards can occur in many different environments, but one of the most common is sidewalks. Sidewalk slabs can often become uneven and raised at the expansion joints because of continuous exposure to varying, and even extreme weather, as well as frequent traffic. As a result, you end up with trip hazards that need to be reduced.
These trip hazards can be drastically uneven between each sidewalk slab. If you were to use a concrete grinder, it would take much longer than a scarifier. The speed and aggressiveness that scarifier cutters offer, makes reducing these trip hazards fairly quick and painless.
We’re not saying that you can’t use a grinder – depending on the size of the trip hazard you may be able to get away with using a grinder, but generally a scarifier is more effective and productive.
Lastly, since it’s a sidewalk, the aggressive profile left behind by a scarifier is ideal for helping to prevent someone from slipping when its wet.
REMOVAL OF CONCRETE GREATER THAN 1/8” (3MM)
When you need to remove concrete that is greater than 1/8” (3mm) thick because of a bad pour or other demolition, a scarifier will be able to do this much faster than a grinder. A scarifier will not only save you significant money in time spent, but also in tooling costs.
THICKER COATINGS
When it comes to coating removal, you could use a shot blaster, grinder or scarifier depending on the coating being removed, operator preference, surrounding conditions etc. However, if you are removing a thick coating and are not needing to polish the floor after, a scarifier will be the fastest most effective form of removal. Not to say that a grinder with PCD tooling can’t remove some of these coatings as well, its just that generally for this coating removal a scarifier is faster and more effective because of its aggressiveness.
END GOAL
What is being done with the floor after the concrete is planed down, or the coating is removed, will have impact on what type of equipment you choose for the job. Because there are so many variables that come into play, its difficult to make a generalized statement that one is always better than another. In some situations, like if you’re looking to achieve a polished finish after a coating removal, a scarifier may be too aggressive, especially if the user is inexperienced. In other situations, grinding will take way too long and won’t give you the profile you need for certain overlays, so a scarifier is a better option. Sometimes using multiple types of equipment is the best option.
Ultimately, choosing your equipment depending on the end goal and the situation is the best way to ensure maximum efficiency and the best results. If you’re ever unsure about what process, or what equipment to use for your job, do some research, or talk to the equipment manufacturer, rental house or dealer you’re getting your equipment from.
At the end of the day, scarifiers are extremely effective for many different types of removal and surface prep jobs. As you gain experience, you will develop your own way of doing things and find which equipment is most effective for your business. However, keeping an open mind about all the options you available to you in the industry will prove to be a benefit.

The Basics of Cutting and Grinding discs

Abrasive-cutting processes are widely used to obtain semi-finished products from metal bars, slabs, or tubes. Thus, the abrasive cutting-off process is applied when requiring precision cutting and productivity at a moderate price. Cut-off tools are discs composed of small abrasive particles embedded in a bonding material, called the binder. This work aims to compare the cutting performance of cutting discs with different composition, in dry cutting of steel bars. To do that, disc wear was measured and disc final topography was digitalized in order to determine both disc surface wear patterns and if the abrasive particles bonding into the binder matrix was affected. In addition, X-Ray inspection gave information about the abrasive grit-binder bonding. Therefore, the method here presented allows identifying discs with a superior abrasive-cutting capability, by combining profilometry and tomography to define micrometrical aspects, grit size, and binder matrix structure. Results led to the conclusion that discs with high grit size and protrusion, high grit retention by bond material, and closer mesh of fiberglass matrix binder were the optimal solution.
[font=”IBM Plex Sans”, sans-serif]Plenty of manual cutting applications call for a hand-held grinder and cutting wheel. Cutting sheet metal, sizing a piece for fabrication, cutting out a weld to refabricate it, and cutting and notching in pipeline work are just a few examples of what can be accomplished using a grinder and cutting wheel.[/font]
[font=”IBM Plex Sans”, sans-serif]Resinoid-bonded cutting wheels are a popular choice to achieve these types of cuts because they offer portability and allow you to cut in many different angles and orientations. The bonding agent, in this case resinoid, holds the wheel together so it can cut effectively. The bond wears away as the abrasive grains wear and are expelled so new sharp grains are exposed.[/font]
[font=”IBM Plex Sans”, sans-serif]By following a few best practices, you can extend wheel life, promote safety, and improve productivity and efficiency within the process.[/font]
[font=”IBM Plex Sans”, sans-serif]The Basics of Cutting Wheels[/font]
[font=”IBM Plex Sans”, sans-serif]The main considerations in using resinoid-bonded wheels include the cutting application, the tool being used—such as a right-angle grinder, die grinder, or chop saw—desired cutting action, the material being cut, and space. Wheels typically provide a fast cutting action, long life, and tend to be cost-effective.[/font]
[font=”IBM Plex Sans”, sans-serif]The two main types of resinoid-bonded abrasive cutting wheels are Type 1, which are flat, and Type 27, which have a raised hub. Type 1 wheels generally are used for straight-on cutting on electric or pneumatic right-angle grinders or die grinders and chop saws, among other tools. Type 27 wheels are required when there is some type of interference and the metal cutting disc needs to be raised up from the base of the grinder, but personal preference also plays a role in the decision. They are most commonly used with electric or pneumatic right-angle grinders.[/font]
[font=”IBM Plex Sans”, sans-serif]Resinoid-bonded abrasive cutting wheels are available in various sizes and thicknesses. The most popular range is 2 to 16 inches in diameter, and common thicknesses are from 0.045 in. to 1⁄8 in. Thinner wheels remove less material during the cut.[/font]
[font=”IBM Plex Sans”, sans-serif]Some types of wheels cut faster than others. The abrasive material used in the wheel is one influencer on cut rate and consumable life. Wheels come in several grain options, such as aluminum oxide, silicon carbide, zirconia alumina, ceramic alumina, and combinations of these materials.[/font]
[font=”IBM Plex Sans”, sans-serif]While not as sharp as other grains, aluminum oxide provides toughness and good performance for cutting on steel. Silicon carbide, on the other hand, is a very sharp grain but not quite as tough, making it suitable for cutting nonferrous metals. Zirconia alumina is a self-sharpening, tough, durable grain that holds up well in a range of demanding applications. Ceramic alumina also is designed to self-sharpen as it “breaks” at predetermined points to maintain a consistent cut rate and long life.[/font]
[font=”IBM Plex Sans”, sans-serif]When selecting a resinoid-bonded abrasive wheel, consider that products made with a mixture of zirconia or ceramic alumina with a harder bond typically cost more but offer durability and longer consumable life.[/font]
[font=”IBM Plex Sans”, sans-serif]Make sure to refer to the manufacturer’s recommendations, product descriptions, and RPM ratings to select the proper wheel size and bonded abrasive material for your application. Matching the size and RPM rating of the tool to the size and RPM rating of the wheel is critical for safe and effective usage. Choosing the tool with the greatest amperage or amount of torque while staying within size and RPM requirements of the wheel will increase performance.[/font]
[font=”IBM Plex Sans”, sans-serif]The kind of tool and the tool guard that you use also are factors that play a role in the type of wheel that can be used for an application. A larger-diameter wheel works best if you’re cutting deep into metal or need to cut a piece with a large diameter, for example, because it eliminates the need to rock the wheel back and forth during the cutting process. Look for a wheel with the diameter designed for the size and thickness of material being cut.[/font]
[font=”IBM Plex Sans”, sans-serif]Thin wheels, such as aluminum cutting disc, on the other hand, tend to remove less metal during the cut and have shorter life spans, but provide a quicker cut. There are some exceptions to this as different versions of thin wheels are lasting longer, so be sure to do your research before you make a final decision to ensure the wheel you select maximizes efficiency.[/font]
[font=”IBM Plex Sans”, sans-serif]Specialty cutting wheels are also available that are designed for use with certain materials, such as stainless steel and aluminum.[/font]
[font=”IBM Plex Sans”, sans-serif]Proper Positioning and Other Tips[/font]
[font=”IBM Plex Sans”, sans-serif]In addition to paying attention to designations for RPM rating, size, and material, you should also follow these tips when using resinoid-bonded abrasive cutting wheels.[/font]

  • Use the cutting wheel at a 90-degree angle, perpendicular to the work surface.
  • Apply the proper amount of pressure—not too much, not too little—to allow the cutting wheel to do the work. Always avoid pushing too hard on the wheel, which can cause the grinder to stall or kick back or give you a much less efficient cutting action. It also increases the chances that you will slip or lose control of the tool, which can cause damage or injury.
  • Choose a grinder with the highest torque or amperage available for the application, as this will help the wheel to do more of the work. For example, instead of using a 4.5-in. Grinder cutting wheel on a 6-amp grinder, use a 4.5-in. wheel on a 10-amp grinder. The RPM rating remains the same, but the tool will provide more torque to cut into the metal.
  • Choose a tool and consumables that offer quick, consistent cutting, which typically provides the most efficient performance.
  • Remember, the thinner the cutting wheel, the more susceptible it can be to side loading, which is a term that describes when the wheel bends while moving side to side in the cut. This can turn dangerous if you lean too hard on a wheel, which can cause the wheel to break or jam in the cut. It can also reduce the efficiency of the wheel and increase the cut time.
  • Store the wheel in a clean, dry environment, and avoid placing it in water or mud. This helps minimize environmental effects that could degrade its performance or cause it to crack or wear prematurely. The performance of resinoid bond tends to deteriorate when the wheel is stored for extended periods of time, so be sure to use FIFO (first in, first out) when using wheels.
  • Inspect the wheel and consumable before each use to check for signs of damage or wear. Cutting wheels, including angle grinder cutting discs can become harder to control as they wear down. If you can no longer make a safe cut because the wheel’s diameter is worn so thin, then the best course of action is to replace it.

[font=NexusSerif, Georgia, “Times New Roman”, Times, STIXGeneral, “Cambria Math”, “Lucida Sans Unicode”, “Microsoft Sans Serif”, “Segoe UI Symbol”, “Arial Unicode MS”, serif]A grinding disc is defined by the type of abrasive material, bonding material, grain size, structure of the wheel, and grade of the wheel used for the machining of a component. These factors decide the grinding efficiency of the grinding wheel and surface finish quality of the machined component. A wide range of abrasives are being used in modern era to overcome necessities in machining of various make of components. Abrasives ranging from the economic verses of aluminium oxide to the likes of super-abrasives such as cubic boron nitride and the expensive diamond grains are used for machining as well as surfacing purposes. Over the years, research has depicted that no distinct abrasive material can meet all the requirements of grinding applications. The mechanical and physical properties of a particular abrasive material make it suitable for a certain application.[/font]

Wire Brushes

[font=”Open Sans”, sans-serif]A wheel wire brush is an abrasive tool that has stiff bristles made from a variety of rigid materials designed to clean and prepare metal surfaces. The filaments of wire brushes are small diameter pieces of inflexible material that are closely spaced together as a means for cleaning surfaces that require aggressive and abrasive tools. The means of applying the brush can be either manual or mechanical depending on the type of brush and the surface to be treated.[/font]
[font=”Open Sans”, sans-serif]The short video below explains the manufacturing of a unique type of wire brush called a wire drawn brush, which is a very sturdy and durable brush that is made by a process that ensures filament retention.[/font]

Automatic Cutting and Stripping Machines

Improved technology enables fast cutting, clean stripping and simple blade changeover for various size wires.
Without a sculptor, a piece of clay or marble can never reach its full artistic potential. Rotary, V and die blades in automatic cutting and stripping machines serve a similar role to help conductive wire and cable achieve its full electric potential as part of a harness. 
Within one or two seconds, these blades precisely cut each wire or cable to a predetermined length and remove its insulation to expose one or more inner conductors. The wires or cables are then manually or automatically crimped by terminal crimping machine before being brought to the assembly workstation, where assemblers use boards to carefully build each harness. 
At Gruber Communications, based in Phoenix, workers assemble lots of cable harnesses for use in data centers every day. The company’s priority since day one has been to produce high-quality cables—and make sure that no cable conductor, or high voltage cable machine is ever nicked or blemished during wire cutting and stripping machine’s processing. 
For more than a decade, Gruber workers used separate pneumatic machines to cut and strip each cable. Eventually, though, CEO Pete Gruber grew tired of the constant maintenance on the machines’ check valves and cylinders. This led him to purchase the all-electric EcoStrip 9300 cut and strip machine in 1998. 
Made by Schleuniger AG of Switzerland, the machine’s reliability and infrequent need for parts has enabled Gruber to substantially increase its cable harness production over the past 18 years. In fact, this machine continues to precisely cut and strip cables after more than 6 million runs. 
Being able to run reliably for nearly 20 years and cut and strip millions of cables or wires is quite common for today’s automatic machines. There are two reasons for this, say suppliers. First is stateof- the art blade technology, which enables fast cutting, clean stripping and simple blade changeover for various size wires. Equally important are operators who understand, implement and optimize each machine’s cutting and stripping capabilities. 
FROM SIMPLE TO PROGRAMMABLE 
More than 90 years ago, Haaken Olsen—an up-andcoming engineer at Artos Engineering Co.—noticed an increased usage of insulated copper wire in automobiles, appliances and radios. He also saw assembly workers manually measuring wire to predetermined lengths, cutting it and removing the insulation from both wire ends. 
Believing manufacturers would be interested in buying an automated machine that could perform this work faster, better and more cost-effectively, Olsen went about developing one. In 1926, Artos introduced the CS-1, the first-ever automatic CAS machine. Olsen vowed to sell at least a dozen, but things went much better than planned. A new industry was born, and Artos alone has sold nearly 100,000 wire processing machines over the past nine decades. 
“Cutting and wire stripping machine machines from the 1920s to the 1950s featured mechanical designs,” explains John Olsen II, president of Artos since 2005 and great-grandson of Haaken. “Typically, three pair of fixed-position blades were used to cut and strip the wire. All setup changes were done mechanically by adjusting cams and moving blade spacers.” 
More-advanced electropneumatic CAS machines appeared in the 1960s and 1970s, allowing for push-button control of feeding lengths. Since then, according to Olsen, CAS machines have evolved in three areas to become much more efficient. 
One is the improved operator interface, which increases the machine’s capability to process small batch sizes and provides full integration with a marking system (laser, inkjet, hotstamp) or slitting device. Another is the use of servomotors for all wire movements to increase processing precision and speed. The third is faster machine changeover by using quick-change guides and blades, and technology like the Artos Sencor system to automate wire setup. 
Semi- and fully automatic CAS machines come in three sizes: benchtop, midsize and large. A benchtop model is best for low-volume and prototyping applications. It usually requires little setup, plugs into a standard 110- volt outlet, and is simple to operate (push buttons, small display, limited programming). 
Despite being an entry-level machine, the benchtop EcoStrip 9380 from Schleuniger can process single wires from 30 to 8 AWG and two wires (up to 0.12-inch diameter) in parallel. It is operated via S. ON software on a 5.7- inch color touch screen, and features the company’s Bricks electronic platform for precise wire feeding by using automatic wire prefeeder. An optional belt feeding system can be set for normal, roller or short mode processing. 
Midsize machines are designed for medium-volume applications, which suppliers define as processing up to a few thousand wires or cables per week. These machines may or may not be standalone, but they are bigger and offer more programming options than benchtop models. 
One such unit is the CS-326 from Artos. The fully electric, servo-driven machine processes wire and cable from 30 to 4 AWG or 0.5 inch OD. It cuts wire to a length of 0.25 inch to 3,250 feet. Minimum and maximum stripping lengths are 0.01 inch and 39 inches, respectively. 
The machine features the Sencor system that senses the conductor within the wire and automatically sets blades at the proper stripping diameter. This technology reduces wire waste, shortens setup time and monitors blade wear. 
Separate accessories enable the unit to cut Kevlar-insulated wire and strip coaxial and ignition cables. An optional work table lets companies easily move the 400-pound machine to any workstation. 
Schleuniger offers six versions of its MultiStrip 9480 machine to cover a wide range of applications (32 to 8 AWG wire) and budgets. Four models (MR, RS, RSX and RX) feature a fully programmable rotary incision unit capable of processing coaxial and multilayer cables. A multiposition indexing cutter head, standard on all models except the S, accepts blade cassettes that change out quickly and easily. The machine cuts and strips wire as short as 2.3 inches and as long as 3,281 feet. In short mode, wires as short as 0.375 inch, with a 0.125-inch strip length on each end, can be processed. 
Large machines are for high-volume (up to several thousand pieces per shift) processing of singleconductor wire as large as 4/0 AWG, and multiconductor or shielded cable up to 1.5 inches OD. These standalone units feature large cutter heads, infeed and outfeed mechanisms, an HMI and multiple protocol interfaces. Users of these machines usually require one to two days of hands-on operations training by the supplier. 
Most large machines can also be networked with other assembly machines via a plant’s ERP and MES software. Manufacturers especially like this capability because it provides full traceability for every job, and enables them to track how many cycles each machine has completed and when maintenance should be scheduled.
 Artos’ CS-327 machine processes cables as large as 4/0 AWG or 1.37 inches in diameter, including battery and welding cables, power cables for appliances, and multiconductor cables for signal and power. The unit’s dualblade cutter head and belt infeed and outfeed systems are servo-driven. Minimum wire cut length is 10 inches in standard mode and less than 2 inches in short mode. Strip lengths are programmable to 40 inches. 
Also standard are an integrated length encoder for accuracy and quality, an HMI for PC operator control and a removable wire scrap collection tray. Options include a three-blade cutter head for high-speed processing and special tooling for steel cables. 
FEWER CHALLENGES THAN BEFORE 
“In the 1950s, the average harness in an American car contained fewer than 50 wires,” notes Rob Boyd, senior product manager at Schleuniger. “Today’s car features many harnesses that have hundreds of wires of varying gauges and lengths. As a result, harness makers need versatile automatic cutting machine and stripping machines to meet this challenge.” 
They also need to make sure that their machine operators are trained to understand the dynamics that exist between wire insulation (depending on wire supplier), nonsymmetrical wire, and blade design and performance limitations. Tim Crider, sales director at Komax Wire, cites as an example the lower margin of error when processing PVC-insulated wire as compared to Teflon-insulated wire. Because PVC is softer and less challenging to cut and strip, the operator doesn’t need to pay as close attention to process parameters, blade positioning and wear. 
Komax’s Kappa 331 machine addresses these and many other challenging applications. It processes wire from 24 to 2 AWG and cable up to 0.63 inch OD in large and small batches. The unit also performs full and partial pull-off operations on single conductors and individual coax layers, and strips the outer jackets from cables with or without shielding. 
A key feature is the Kappa Sensorik laser sensor, which automatically detects the wire conductor and uses inductive measuring to determine its diameter. The sensor and a chargecoupled device (CCD) line optically measure the outside cable diameter and then check that the cable is present during processing. This feature greatly shortens setup time and changeover, and reduces operating errors. 
For the past 18 months, a large wire harness and cable manufacturer has been using the Kappa 322 machine to cut and strip three-conductor 14 AWG cable (40 inches long) at a rate of 600 pieces per hour (pph). This midsize unit processes wire from 30 to 4 AWG and enables easy setup and changeover without tools. 
“Buying a midsize machine to constantly perform heavy-duty work is a common problem,” says Armando Zacarias, sales and service manager at Eubanks Engineering Co. “A machine that’s capable of processing 32 to 8 gauge wire is really not designed to process 8 gauge wire all day long. Using the machine that way will likely require it to often be refurbished or rebuilt. A better approach is to buy a machine that’s able to process wire as large as 4 gauge.” 
Operators use a cassette to quickly insert and remove blades from Eubanks’ fully programmable AirStrip 7400 machine. Microprocessor-controlled and easy to operate, the machine handles stranded conductor wire from 32 to 8 AWG, and multiconductor cable up to 0.31 inch OD. It strips cable up to 20 inches long, and can be programmed to do step and center stripping. 
A bit larger in size is the more powerful 2700-05. It cuts and strips wire from 32 to 8 AWG, as well as multiconductor and flat cable up to 0.31 inch wide. Operators input wire processing parameters on the built-in keypad. Zacarias says consumer electronics and automotive manufacturers use this machine in high-volume, low-mix environments because of its high production rate (up to 10,800 pph). 
Another ongoing challenge is making the wire and cable as straight as possible before it enters the CAS machine. Suppliers often provide material on the smallest spool possible, which, unfortunately, results in bent wire and cable that may require a straightener. 
To avoid this extra processing step, Boyd recommends thin wire be wrapped around spools at least 10 inches in diameter. Thicker wire and cable should be delivered on much wider barrels, so that it unwinds in a large loop that is easy to straighten.

Algorithm for cutting rods with minimum waste

Given a set of cuts and their lengths we need to find out the minimum number of rods (of constant length) and the cuts required which will lead to minimum wastage.

Here we bundle the rods and cut them all at once. So we can have a bundle with any number of rods.

For example:

Input data – Consider a rod of length 120 inches

( Quantity of Cuts Required, Length (in inches) ) = (5,16") , (5,30") , (24,36") , (4,18") , (4,28") , (6,20")

So here we required cuts such that we get 5 rods of 16 inches, 5 rods of 30 inches..so on.

Output:

Imagine each row (in the image) is a rod of 120 inches and each table is a bundle with rows as the number of rods in that bundle. So the first table is a bundle with 5 rods with cuts [16,30,36,36] and second table is a bundle of 4 rods with cuts [18,28,36,36] and so on. We can see that we have satisfied the input data we get (5,16") five rods of sixteen inches and so on.

enter image description here

Given input with (just like above) number of cuts and their lengths. how do we find the bundle of rods and their cuts having minimum amount of wastage?

Cutting Words timing when playing online

Lore Bard’s Cutting Words feature states the following:

Also at 3rd level, you learn how to use your wit to distract, confuse, and otherwise sap the confidence and competence of others. When a creature that you can see within 60 feet of you makes an attack roll, an ability check, or a damage roll, you can use your reaction to expend one of your uses of Bardic Inspiration, rolling a Bardic Inspiration die and subtracting the number rolled from the creature’s roll. You can choose to use this feature after the creature makes its roll, but before the DM determines whether the attack roll or ability check succeeds or fails, or before the creature deals its damage. The creature is immune if it can’t hear you or if it’s immune to being charmed.

What exactly does that mean. At what time do I have to say my DM I interrupt them?

When playing at a table, my DM usually goes this way: “The goblin attacks [player character] with their bow and [rolls] hits”. I can hear the dice roll and I say I want to know the result in order to decide if I want to use Cutting Words.

Now with the current sanitary situation, we play online, and the DM usually rolls their own physical dice and tells whether it hits or not because they have all our ACs registered. This basically forbids me to use my Cutting Words.

So what is the exact timing where I can interrupt the DM, online, and use my Cutting Words?

Optimal substructure of rod cutting?

How do you show the optimal substructure of the rod cutting problem(defined as in Optimal substructure and dynamic programming for a variant of the rod cutting problem). I am trying to follow the guideline steps enter image description here

So suppose someone told us one of the cuts of the rod $ R$ in an optimal solution OPT for $ R$ .

This cut of OPT paritions $ R$ into two smaller rods $ R_1$ and $ R_2$ , one of length $ i$ , and the other of length $ n-1$ .

Here is the only argument that I can think of: (Again, trying to follow steps 3 and 4 now but the argument does not seem like one that would suffice)

Suppose that $ R_1$ is not an optimal solution in itself, then OPT would not have given an optimal cut in the first place which contradicts our starting supposition that OPT is an optimal solution.

Also, the argument seems too “easy” to appear like something that is not just informal.

How would you prove the optimal substructure?