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Technology Focus

Saving Time on Set-up

by Carla Davenport

August-September, 1998
We've all heard the saying, "A penny saved is a penny earned." But what about time? Saving even a few minutes on a job can translate to dollars, not just pennies. And a job well-planned is (more often than not) a job well done. All puns aside, more companies are finding that set-up time is more critical to getting a job done efficiently than the overall speed of a press or a cheaper price on foils and dies. You may save a few dollars on materials, but if they require longer set-up times, you may end up spending more on labor than you saved on the so-called "bargain" materials.

So what can you do to save set-up time without scimping on quality? InsideFinishing has done some sleuthing, and coaxed several industry insiders to let us in on their time-saving tips. Here's their step-by-step advice:

Hot off the Press

Heating up the chase can take several hours, depending on the type of press you are working with. Connecting the heaters to a timer, and programming it to come on at a pre-set time can ensure that the press is ready when you are.

In addition, pre-planning your production by job type can save time. Temperatures vary according to the type of job being done, such as foil stamping, embossing, and die cutting. Taking this into consideration can help you schedule jobs more efficiently. Try to schedule the same types of jobs one after another, so you don't have to adjust the temperature of the chase as often. Also, avoid partial runs, and running different size jobs back to back when possible. If you can move a job forward in your schedule that is similar in size to the current job on press, a considerable amount of time can be saved on adjusting the press for different sheet sizes.

Feeding the Sheets

Computerized feeders are the newest way to cut feeder set-up time, but they're not feasible for every company's budget. If you can't afford to computerize, setting up the feeder while dies are heating can save valuable time.

When it comes to feeding, the quality of the sheets you are working with can affect the efficiency of the run. If sheets are curled or warped, set-up time will be increased. Some pre-planning with customers can work to your advantage later on. Train your customers to square the sheets for you. At a minimum, have your customers trim the gripper and guide sides of the sheets, and when possible, trim all four sides. Also, make sure they mark the guide and gripper, and ask them to ensure the sheets are bound and skidded in a way that keeps them flat.

When the sheets are being printed off-site before coming to your facility, communication with the printer before the job begins is essential to minimizing slow-downs during the set-up and running of the job. More than 75% of on-press problems may be attributed to the lack of communication between the printer and finisher. Gaining strong relationships with your customers helps ensure a consistent work-flow through your finishing operation.

The Key to Lock-Up

Lock-up is one point in the set-up process when taking a little extra time initially can save a lot of time later on. Once you have heated the chase, adjustment to dies is almost always necessary due to the expansion of metal. These adjustments can be tedious because the press has been heated to 200 to 250 degress, if not hotter. Reciprocating platen presses require pulling the chase out of the press and flipping it over to make adjustments. Dies mounted on the lower portion of a clam-shell chase can be difficult to get to as well. The patience of a careful operator, taking his/her time to do the best initial positioning possible, can greatly reduce the time of taking a chase in and out for adjustment once it is heated.

One way to help ensure proper time is taken to set-up the die on the chase before it is heated on press is to have an extra honeycomb chase for each press. This will allow operators to do lock-up for the next job while the current job is running. This may be the most essential recommendation we discuss. When a job is running smoothly, an operator can be setting up for the next job rather than standing and watching a press. Of course, challenging jobs may not allow this, but there are many runs that will. Additional honeycomb chases should be available from your press manufacturer or from sources who specialize in building chases, including Chase Engineering, Eagle Systems, Inc., and Sterling Toggle, all regular advertisers in InsideFinishing. (Check out the Links section or the FSEA Online Directory.)

String 'er Up!

The only solution to decreasing the time it takes to string up foil is to avoid re-stringing. By taping your new foil to the end of the last job's foil, you can advance it through the press and avoid stringing and removing foil for every job. This is a simple recommendation, but it can save as much as 30 minutes or more, especially on larger platen presses.

Registration Issues

A skilled operator can hold good consistent register on most equipment, but there is a limit to tolerances. For instance, jobs using light-weight paper can be especially tough to maintain register. One recommendation for this is to try filling in blank areas of the honeycomb with 1/4" foam rubber between the dies when a job requires several dies for one run. This will allow the sheet to lay flat as it is being stamped and provide more consistent registration throughout the job.

Again, educating your customers on the tolerances your press can consistently hold will help them get the quality they want. Offer suggestions on how a job can be designed or laid out within the tolerances you can maintain. Also, make sure the printer knows not to reverse out the image or type to be stamped. This is probably the number one 'no-no' that happens consistently in foil stamping. Printers believe they are doing you a favor by reversing out the type that must be stamped. As foil stampers know, this creates more of a headache and longer set-up times. There cannot be enough emphasis placed on the up-front communication that is needed to keep set-up and production times to a minimum.

Keeping Consistent Pressure

Consistent pressure is the name of the game. Theoretically, if your press, dies, foil and paper are perfectly and consistently flat and level, you will only need to adjust the overall pressure to achieve a perfect impression. Not a likely scenario.

Two things directly affect consistency of pressure on a press; deflection and levelness. Deflection is the amount the head and platen bend, distort, or deviate from their natural, flat condition. The amount of deflection a press has is a direct result of its design and engineering. While you cannot improve upon the amount of deflection your current equipment has, you should inquire about deflection when looking into new equipment. Ask the manufacturers you are considering how they quality assure minimal deflection and what guarantee they offer that it will not exceed a certain amount under full load.

Load cells provide one way to measure the deflection on a press. The cells guage the pressure in various areas of the press and calculate the amount of deflection at each pressure setting. This is a great way to quality assure minimal deflection. Some equipment manufacturers use this technology. If you're interested, have your current equipment tested by an independent company.

Check the level of your press periodically as well. The constant up and down motion of a hot stamping or die cutting press can make a press become unlevel in a short period of time.

Don't Cut Corners!

Keeping your press in good working order with preventative maintenance is one of your best defences against unwanted down time. It is a good idea to begin a maintenance program that is monitored on a consistent basis for all of your machines. One suggestion is to have a check list of everything that should be monitored. Some parts of the press will need to be checked daily, while others weekly or monthly. The system you put in place is up to you. The key is to make sure there is a maintenance program to keep your presses in good working order.

Another suggestion is to use die suppliers that can quality assure the consistency of thickness in the dies they manufacure and supply. Don't try to save a few dollars on dies that are not well made. You will end up losing all the money you saved on dies with additional makeready time on press.

The quality of hot stamping foils and paper can also affect consistency. You may be "stuck" with the paper you get from customers, but working closely with your foil supplier to ensure that you order the correct foil for the job can be the difference between a successful or a difficult run on press. Ask them to specify the right foil product for the inks, coatings, and paper type you are working with. Also, try to get a few sheets of the printed job two or three days in advance of receiving the entire order. This can provide time to test different foil formulations and choose the one that will run best when the entire job is ready.

Faster is not Always Better

Another general mistake that many finishers make is that you should always try to run a job on the fastest press available. This is not always the case. A press that can run a job at 3,000 sheets per hour is not necessarily the best choice if set-up time (on average) is longer. Let us look at the example below:

Set-up Time Press Speed Run Length Total Job Time
1 Hour 2,000 SPH 5,000 3.5 Hours
2 Hours 3,000 SPH 5,000 3.67 Hours

As you can see, the press that runs at 2,000 sph actually completes the job faster than the press that runs at 3,000 sph because the set-up time on the smaller press is about 50% less. This same rationale can be applied to the cost of materials as well. Consider this example:

Unit
Price
Foil
Needed
Foil
Cost
Set-Up
Time
Press
Speed
Run
Length
Total Job
Time
.078 2,500 LF $195.00 1 Hour 2,000 SPH 5,000 3.5 Hours
.066 2,500 LF $165.00 2 Hours 2,000 SPH 5,000 4.5 Hours

In this example the customer saved $30 on hot stamping foil, but increased set-up time considerably because the foil was not compatible with the job on press. These two examples demonstrate how important pre-planning and set-up can be to the bottom line.

With all of the recommendations and tips we have discussed, communication and planning is still at the heart of all successful jobs. Developing close relationships with your suppliers, equipment manufacturers, and customers can smooth out problems before set-up even begins. Yes, there are specific procedures that can be followed to decrease your overall set-up time. However, pre-planning and communication will always be your best defense against unnecessary time on press.

InsideFinishing would like to provide a special thanks to Kent Allen of Preco Industries (800-966-4686,) for his indepth contribution to this article, with additional thanks to Cheryl Baier of Independent Machinery, Inc. (847-991-5600,) and Kenny Noonan, of Eagle Systems, Inc. (800-6EAGLE9) for their assistance.