Wednesday, March 31, 2010

Kiss Die Cutting

Written By Mark Batson Baril

We started with this Question:

We are a small Die cutting shop that produces flat labels and decals. For years now we have run kiss cut jobs. The problem we have run into is on the more intricate, and complex jobs. In some areas we will produce a perfect cut and in other areas our cut will only dent the surface without even penetrating the label material. We consistently use the same backer or liner which is a 90 lb stock, approx. .010" (.254 mm) thick. We have been told by some industry people that we would get better results cutting into a thinner backer for these complex Kiss cut jobs. Is there any truth to this and do you have any other suggestions for us?

There are many potential problems and/or combinations of problems that an cause uneven cutting, especially when Kiss cutting.

Possible Problem: Not enough tonnage on your press.

Check: Have you run larger dies (with more lineal inches of cutting) on your press without problems? If so, then this is not the problem. Note that a great deal of cutting in a very small area requires a larger amount of tonnage to cut. Also, a dull knife requires more tonnage to cut.
Solution: If a lack of proper tonnage is the problem, then reduce the number of cavities in the die, spread out the cavities, use a larger press or reknife the die.

Possible Problem: Your Press is not level.

Check: When one side/section of the die is not cutting deep enough, rotate the die 180 degrees in the press. If the problem area follows the die, it is generally a die problem. If the problem area does not follow the die, then it will be a press problem.
Solution: Die problem - have diemaker correct the die. Press problem - level the press or replace the cutting plate. Also the use of "stop blocks" in the die will help and sometimes eliminate this problem.

Possible Problem: Diecutting pressure is not centered in the press.

Solution: Make sure the cut to cut area is centered on the press. The exception is when the die has a large amount of cutting concentrated in a smaller area, move this area closer to the center of the press. Balancing the press is key in every situation. A rocking press will never Kiss well.

Possible Problem: Cutting rule in die is not level.

Check: Make sure the back of the die is level. You may not be able to notice .003 to .006" offset in the knife. The knife may be too tight in the diebase and cannot be leveled correctly. Check for any debris under the back of the knives. Wood or other material may have worked its way under the back of the tool.
Solution: Send die back to diemaker for inspection and/or correction along with a couple sheets of your material and sample die cuts.

Possible Problem: Cutting rule is dull or just not sharp enough.

Check: Check to see if you can see shiny areas on the cutting edge of the knife. This may be caused by (1) The diemaker's bending dies not being squared up which will flatten the edge during the bend; (2) improper handling of the knife during the cutting, mitering, bending and/or insertion of knife into the diebase; (3) the knife was dull to start with; (4) the knives were damaged after the tool was made.
Solution: Again, ask your diemaker to check the die (send sample cuts with returned die). Also check incoming tools and just off the press tools for wear spots. Remember, that first impression can be a killer. Ask your diemaker these same questions and make sure he is confident that he is supplying you with a flat tool/ ± .0005 flatness in the rule is fast becoming the industry standard. In some cases the radius areas will need to be broached (steel removed) prior to bending the knife. This results in a flatter rule at radiused areas.

The question at hand: Yes, you may get better results cutting into a thinner/harder backer material. Your .010" (.254 mm) thick liner material will cause you problems when the cutting edge of the knife is not sharp or when the material being cut is a thin mylar or vinyl. These materials have a tendency to stretch not cut especially when the liner us softer. Many times you can go with a thicker liner which will allow for more slop in the cut and still allow for a partial cut that looks good. Just remember that you always want to cut into the softer material first.

Before you reach any conclusions on the backer material it would be worth going through the above problem solving areas to try and find the real cause. The cause may be in the die, the press, the operator, the material, or perhaps in a combination of two or more.

Thursday, March 25, 2010

Cutting Polystyrene Without Angel Hairs - 101

This question was put out to a network of Tech Heads to find a fast cutting edge solution. We thought it would be fun to show the results just as they came in – one at a time.

We are cutting 24 mil Styrene (polystyrene) on a flat bed Bobst machine. The material gets angel hair hanging off the edge. Is this a characteristic of the stock or is there something we can do to eliminate the angel hair?

1. It is a common characteristic of styrene materials. We have experienced the same situations on many occasions because of the material and the way the die cuts it, bursts through the material and hits the bed harder than normal, thus dulling the die itself. (Tom with Larkin Industries)

2. This sounds like the same problem stuff we used to work with for promotional model airplanes. The best results are had with a special razor rule 1.5 points with an extreme 30 degree bevel angle, and about a 65RC Hardness. This is only made by one company I know of. I can't remember all the details but the trick seemed to be in the steep angle. (Mark Baril from Cut Smart)

3. Maybe I'm doing something wrong too, because I have always had trouble with fine hair on styrene. If you get a plausible answer back from someone, could you let me know? (John Mechetti from Mechmar Industries)

4. Without more details, it may be difficult to pin down the specifics of the problem, such as type of rule used, configuration of the part and spacing layout, ejection being used, etc. A quick answer however may be to glue a piece of mylar (.007) or hard oak tag stock (.010) on the cutting plate. This may remarkably improve the situation. (Allen Gurka)

5. We used to cut styrene on a hand fed platen press and found that the only way to eliminate angel hair was to use a very sharp die and cut with either something underneath (like paper) or to not cut completely through and then pull the part out of the web. Maybe others know better methods. (Fred Antonini from Cutcraft)

6. I have tried all kinds of cutting rule to get rid of the angel hair problem with diecutting polystyrene. We use Bohler Universal Supreme 45 degree cutting rule .937 2 pt. We also use a cutting rule called Mpower. This is made by Atlas Die in Elkhart, IN. This works the best so far. I went from 300,000 impressions to a million impressions on die re knives with the Mpower rule cutting .013” polystyrene. This has not gotten rid of all the angel hair; we still get some once in a while. I believe it is caused in the mixture of the plastic some how, because you will run one lot and have very little, if any, angle hair, and in the next lot it will be all over the sheet, but the Mpower rule helps to eliminate the angle hair and if you use a water jet rubber so the rubber is away from the knives this has helped a lot also. We use a T-75 tiger-x rubber. (Leo Moore from Master Tag)

7. Angel hairs are caused by dulling of the rule. If you have sharp rule, as it enters the material, and penetrate to a set depth, the material fractures the rest of the way. Much like splitting a log with an ax. However, when the rule dulls, you have a flat spot on the edge of the rule, as it penetrates the material it actually holds the material in place on both sides of the rule edge. As the material fractures there are two fracture lines through the material. This causes a small "hair" on the sides of the cut part. The hair becomes more pronounced as the rule keeps getting duller. There are three solutions that I know of on how to reduce the hairs:

    1. Add heat to the tool which reduces the fracture point. Approximately 190 degrees. 2. Preheat the material to reduce the material rigidity. 3. Use extremely sharp rule reducing the stress of the material as the rule enters it. I have had good luck using Tsukatani 30 degree bevel with a ground and polished edge, however, Sandvik and National also make a similar rule that I am sure would work just fine. Standard rule is 42 degrees and that causes too much friction going through this type of material. (Randy Norman from Preco)

WOW....that's a lot of knowledge!
The common threads that may lead you to a solution in your shop include:

  • Know your material and your supplier so you get the same type of plastic every time.

  • Get yourself a very steep angle cutting edge knife to help penetrate the material.

  • Cut against a cutting blanket that will not dull the knives or spend some extra time in make-ready when cutting against steel.

  • Keep a close eye on tool maintenance. Does the job start with perfect results and deteriorate to angel hairs? If so work to keep the blades sharper or replace them more often.

  • Add heat wherever you can. To the tool or to the material.

    Good Luck!

  • Thursday, March 18, 2010

    Inexpensive Starter Presses for Die Cutting

    Written By Mark Batson Baril

      Hi! I'm a designer in Pittsburgh specializing in custom-designed invitations, programs, etc. for special events. 90% of our work is made by hand. I'm looking for a desk-top sized hole-punch unit that could punch from 1 to 5 1/8" holes with approx. 1/2" spacing between the holes in sheets of paper. I also have other shapes that need to be cut in small quantities. Do you have anything like this or can you recommend anyone I could contact? Thank you! More Than Words

      Sirs, I own a small business and have all of the equipment needed to manufacturer neoprene can coolers, except something to cut a 2 1/2" circle of 5mm thick neoprene. I had a die made and attempted manual procedures, such as using an arbor press and even just a rubber mallet. I just can't get enough pressure to cut through the rubber. I don't want to spend a fortune on more equipment. Do you have any recommendations? Lou Frazier

      HI Cutting People My husband and I own a small specialty credit card manufacturing business in New England. We print and then laminate sheets of paper with a heavy plastic that makes them feel and look like credit cards. Currently we cut these out with a blade on a table. Our quantities are increasing quickly into hundreds per week and we would like to put a round corner on the cards too. Do you have any suggestions? Linda Quinn

    These three situations have been dealt with time and time again. All three of the questions have similar elements that make for a common answer that makes a whole bunch of sense.
    The common elements are:
    • They are Small businesses with limited cash resources.
    • They probably operate out of their homes so they need small machines that won’t; wake up the neighbors, need three phase power, or need an army and a crane to lower into the basement.
    • Quality cuts are needed to produce a high visibility product.
    • Low tonnage needed – max. of probably 5 tons.
    • Shapes to be cut are all conducive to using steel rule dies as the cutting tool.
    • Low quantities mean that a hand operated press will work fine. High speed cutting and stripping are not concerns at this point in their businesses.

    There are probably a dozen types of presses out there that could be used for these applications. There are the standard presses from the hydraulic clicker to the clamshell to the pneumatic punch press style that are all still a bit on the over-kill side. They would not be a good total fit for the situation. There are at least two really cool machines on the market today that are the perfect fit.
      1. They are hand operated presses that develop the pressure needed. 2. They are cheap to buy – less than $500.00 US. 3. They cut a reasonable size image (max. 9² x 12² approx. – 228mm x 305mm), 4. They are small and lightweight and take relatively little training to use. 5. They can use steel rule dies as there cutting tools and can also be used for embossing. 6. They are safe to use.

    The Ellison Machine is a bearing equipped cam operated type machine that acts as a flatbed platen type cutting press. A large handle allows the operator to make the impression with little effort while maintaining excellent registration and cut quality. The press is a table top model and is very safe to operate.

    The Accucut Machine is a roller press type machine that acts as a flatbed platen type cutting press with pressure being exerted as the die passes under the top roller. This press is also a table top model and is quite safe to operate.

    Both machine companies will take a sample of the material to be cut and the tooling you own or a in stock tool they own and will do test cuts. This allows a real live test so the customer won't buy a machine that will not work for their business. What a deal! Both companies also act as suppliers for custom and stock steel rule dies and embossing tools.

    If you strike out with the presses, one other route may be to have an outsource shop cut the parts for you. It could be quite cheap and maybe a good route to take. A local die cutter, laser cutter, Water jet cutter, sample cutter or prototyping house will be able to help out in any of the question cases outlined.

    Thursday, March 11, 2010

    Metric VS. THe English System of Measurement

    Just about daily we battle between using the Metric System of measurement and the English system of measurement. Some of our customers use only the Metric system while most still use the English system with a bit of Metric thrown in here and there. Let's explore the question of which came first as well as the bigger question; are those companies in the USA the only ones in the World that are still dragging their feet on this issue?

    Going as far back in time as the story of Noah's ark, the lack of a yardstick was not a serious drawback. Most measuring was done by one craftsman completing one job at a time, rather than assembling a number of articles piece-meal to be assembled later. It didn't make much difference how accurate the measuring sticks were or even how long they were. Generally, it doesn't make much difference how long a mile, a yard a meter or an inch are or how heavy a pound or an ounce is. What is really important is that everyone means the same thing when referring to each unit of measurement. Measurements must be standard to mean the same thing to everyone. Imagine your business with no way to measure the product...

    The First Yard
    When the Roman Empire passed into history about six hundred years after the time of Christ, Europe drifted into the Dark Ages. For six or seven hundred years mankind generally made little progress with regard to standardizing measurement. Sometime after the Magna Carta was signed in the Thirteenth Century, King Edward I of England took a step forward. He ordered a permanent measuring stick made of iron to serve as a master standard yardstick for the entire kingdom. This master yardstick was called the "iron ulna", after the bone of the forearm, and it was standardized as the length of a yard, very close to the length of our present-day yard. King Edward realized that constancy and permanence were the key to any standard. He also decreed that the foot measure should be one-third the length of the yard, and the inch one thirty-sixth. King Edward II, in 1324, reverted back to the seed concept of the ancients and passed a statute that "three barleycorns, round and dry," make an inch. However, seeds as well as fingers and feet were no match for a world that soon was to emerge from the ignorance and unrefined practices of the Dark Ages.

    The First Meter
    As the scientists were experimenting in their laboratories, practical tradesmen were making themselves permanent standards. In 1793, during Napoleon's time, the French government adopted a new system of standards called the metric system, based on what they called the meter. The meter was supposed to be one tenth-millionth the length of the distance from the North Pole to the Equator when measured on a straight line running along the surface of the earth through Paris. With the meter now determined as the basis of the metric system, other linear units of the system were set up in decimal ratios with the meter. With this system, all units are in multiples of ten: ten decimeters in a meter, a hundred centimeters in a meter, and a thousand millimeters in a meter. In the other direction, there are ten meters in a dekameter, a hundred meters in a hectometer, and a thousand meters in a kilometer. Compared to the yardstick, the meter is just a little longer: 39.37 inches long.

    The French government thought it had an infallible system of weights and measures that would be easy to use and would be embraced by everyone. But people were accustomed to thinking in terms of yards, inches, pounds and quarts. At first the new meter as a measure of length proved confusing. Most Frenchmen thought in the old familiar terms, doing some mental arithmetic to convert one quantity into another and, after nineteen years, Napoleon finally was forced to renounce the metric system. However, in 1837, France again went back to the meter, this time for good, hoping to make it universal throughout the world.

    While France was evolving the metric system, England also was setting up a more scientifically accurate determination of the yard. Where the French relied on the assumed constancy of the earth's size as a basis for the permanency of their standards, the British turned to the measured beat of the pendulum. Galileo already had learned the secrets of a pendulum. He found that the length of time it took for a pendulum to complete a swing depended upon the length of the pendulum itself. The longer the pendulum, the slower it swung. He also found that a pendulum a little over 39 inches long would swing through its arc in exactly one second. Since a pendulum always behaves exactly the same way under the same conditions, here was another unchanging distance upon which to base a standard measurement.

    In 1824, the English Parliament legalized a new standard yard which had been made in 1760. It was a brass bar containing a gold button near each end. A dot was engraved in each of these two buttons. These two dots were spaced exactly 1 yard apart. The same act that legalized this bar as the standard for England also made the provision that, in the event it was lost or destroyed, it should be replaced using the pendulum method to determine its length. A few years later, copies of both the English yard and the French meter standards were brought to the United States. The English system of measuring was almost universally adopted in the United States.

    In spite of repeated requests in Congress, there was no legal length standard in the U.S. until 1832. More or less authentic copies of the British copies of the yard were used as length prototypes. In 1832, the Treasury Department decided to admit as a legal Yard the distance between the lines 27 and 63 of a certain bronze bar, 82 inches in length, bought in 1813 in England for the Federal Survey Department. When the British yard bar, which was destroyed in 1834, was replaced in 1855, a new bronze copy No. 11 was sent to the United States which became the legal American Yard Standard.

    Converting the United States
    Since the mid nineteenth century the United States has made several attempts at converting over to the World Standard. On May 20, 1875 the United States became a charter member of the metric club, having signed the original document (The Treaty of the Meter), in Paris. They were the only English-speaking nation to do so. Since then, 48 nations have signed this treaty, including all the major industrialized countries. In 1975 the US Congress passed the Metric Conversion Act and although made with good intentions, the Treaties, Acts, established Institutes, and passed legislation have yet to push through the change.

    To answer the second half of the question - it is not true that the US remains the last holdout. While the rest of the world is pretty much standardized on the metric system of measurements, when it comes to mandatory use, the United States has company in its foot dragging. Great Britain, Liberia and Burma are right there along with the United States. Some international organizations have threatened to restrict U.S. imports that do not conform to metric standards and rather than trying to maintain dual inventories for domestic and foreign markets, a number of U.S. corporations have chosen to go metric. Some Motor vehicles, farm machinery, and computer equipment are now manufactured to metric specifications. We have a feeling that you will be seeing more and more of your customers in the US using the Metric system in their purchases with you as their customers make more and more original specifications in Metric.

    One More Important Thing To Know: SI is the abbreviation for the Système International d'Unités, the modernized version of the metric system that most nations have agreed to use. It defines the length of a Meter as the distance light will travel in a vacuum in 1/299,792,458 of a second. Talk about calibrating your measuring tools!

    Thanks goes to Cool Fire Technology for the reprint permission on much of the History contained here.

    Written By Mark Batson Baril

    Wednesday, March 3, 2010

    One of those random post

    Hello Everyone!

    Well I have been gone for two weeks and our views have doubled! Hooray! And we even have our first follower! I am going to be happy for what we have instead of being sad for what we could have be positive right?

    I have now been here for 4 months and it's crazy how I'm still blown away by all the different ways you can cut things, or how many questions still boggle my mind. Measurements, materials, shapes of cutting, and all the ways you can cut it. 
    A great tool that we offer on our website that helps me all the time is called our Best Manufacturing Process Calculator. If your taking this moment to read this blog then you should take that extra moment to click on that link. Honestly a great tool, any thing you can think of cutting, any measurement that you can think of that Calculator will do its best to help you.

    I hope everyone has enjoyed our blog and learned some new interesting things. I would really love some feed back from anyone with any questions, or if you would like to start our next blog topic? We are here to share everything we know about die cutting, and helping everyone learn anything that they might need to. Yes these blogs even help me understand everything a little bit more. 

    Again, feel free to ask any questions, leave a comment or even take that other extra moment you might have to become another follower! I would really appreciate it. 

    Hope everyone's March is going excellent!!!