by John Kaverman, Pad Print Pros, LLC
Recently, I’ve been in two different companies to install pad printing systems and to train their operators. Neither of the companies was prepared for either the installation or the training. Unfortunately, this happens all of the time. Many companies fail to adequately prepare to receive a new piece of equipment or schedule dedicated personnel and time for training. As a result, valuable training time is lost, and the training is not as successful as it otherwise could (and should) have been. There are simple things that can be done to help maximize installation and training time.
Environment: The environment should be clean, organized and, ideally, climate-controlled and properly ventilated.
At a minimum, the room or area where the machine will be installed should be cleared of clutter and swept. Paying me to come in to the plant and push a broom doesn’t make sense. As a “clean freak,” I don’t mind pushing a broom, and I certainly don’t think the task is below me. However, there are better uses of my time.
Pad printing, like any printing process, works best in a controlled environment. Even if the facility doesn’t have an air-conditioned space in which to print, the negative effects of variations in temperature and relative humidity can be minimized by keeping the machine out of thoroughfares (where dust and dirt are stirred up by constant traffic, and rubber-necking personnel cause distractions) and away from outside walls and areas where drafts are common (overhead doors, beneath heat ducts, etc.).
Adequate ventilation is important, especially in the area where operators will be mixing ink and cleaning ink cups, cliché plates and other accessories. Once the ink is in the cup and hermetically sealed to the cliché plates, the odors shouldn’t be a problem (unless the ink cups are poorly designed and/or poorly maintained).
Making polymer clichés in-house: Have a UV-free zone available in which to work.
When making polymer clichés in-house, the work area needs to be free from ultraviolet (UV) light. Overhead fluorescent or similar lights need to be shielded so as to prevent the emission of UV wavelengths, or an alternative UV-free light source needs to be available. In a pinch, operators can work in any room that doesn’t have windows and a yellow “bug-light” (which is filtered to prevent the emission of UV wavelengths that bugs are attracted to) can be used.
Cliché blanks should be stored in a UV-free zone until they’ve been exposed and developed.
Utilities: The correct power and, if necessary, compressed air need to be available.
Even though my quotes specify the correct power requirements for the equipment being installed, many companies fail to ensure that the correct power is available until I show up. As a result, I lose half a day of training time running to the nearest Builder’s Square or Grainger store to pick up the correct plug or parts to plumb in compressed air for pad and part pre-drying.
Check with the equipment supplier to ensure the correct receptacle is on hand simply by taking a digital photo of the receptacle and messaging or emailing it to them. If the supplier ships without a plug installed (as some manufacturers do), coordinate ahead of time to ensure that the right plug is available to wire the machine in once it arrives.
If installing a pneumatic machine or accessories for pre-drying pads and parts for faster multiple-color printing, make sure the necessary regulator(s), hose, fittings and accessories (such as Loc-Line) are on hand.
If there’s any question about what is needed, ask the equipment manufacturer for recommendations. Personally, I prefer to have enough Loc-Line available to plumb two nozzles in for every print station (one for the part and one for the pad), with enough in-line flow controls to adjust air volume to each nozzle independently.
Tools: The correct wrenches, screwdrivers, screws, nuts, bolts, etc. should be available.
Most pad printers use metric Allen/hex wrenches. I recommend a set with ball driver tips for use on weird angles. Depending on how pads are affixed to pad couplers, specific metric screws (if the pads have threaded inserts in their bases) or short wood screws (which won’t go all the way through the wooden bases of the pads) and something to drive them (either an adequately sized screwdriver or a cordless drill with appropriate bits) might be needed. Pliers and perhaps a set of vice grips also are a good idea.
If the installing technician is bringing his or her own tools, go out and buy whatever he or she uses while the technician is on site. That way, the installing technician can evaluate the tools on hand and point out anything that will be needed once the install is complete.
Ink mixing/cleanup supplies: It is important to have ink mixing and cleanup supplies and equipment ready.
Pad printing inks should be mixed by weight, so a good digital scale is very important. If color mixing and matching will be performed, the scale should be accurate to 0.01 grams. If inks simply will be blended with thinners and/or hardeners, .10 grams is sufficient.
Disposable plastic pipettes, mixing cups and stir sticks are essentials. No-wax paper cups or plastic (PP or PET) cups and large or small tongue depressors are cheap, quick and easy to use when mixing ink.
Don’t waste time and money on glass or stainless steel mixing vessels and stainless steel spatulas that must be cleaned. Plus, re-using vessels and spatulas can contaminate inks. Disposable plastic pipettes are great for metering thinner into inks, and the pipettes are a lot less messy than trying to pour ink out of a can or cup. Thinner dispensing bottles with angled capillary “squirt” tubes also work well.
A plunger can works great for dispensing cleaning solvents when cleaning ink cups and accessories. Again, these are a lot less messy than pouring solvents out of a can.
I prefer to use absorbent towels or tissues for cleaning. Cheap facial tissue (without aloe or perfumes) can work well, although lint-free wipes are required when working in a cleanroom environment.
Finally, a good fireproof can with bag liners is essential for disposing of used ink cups, stir sticks, pipettes and towels or tissues. Having a lid on the can that is foot-actuated will help minimize the usually unpleasant smells associated with ink mixing and clean-up.
Work surfaces: Prepare a space to work on.
A sturdy, level surface for mixing ink and clean-up is needed. Ideally, the following should be within reach: tools, tissues, a plunger can, ink mixing cups, sticks and pipettes. I recommend a 4’x6′ table with a stainless steel top. If stainless steel isn’t available, plan on covering the surface with a media that can be disposed of when ink and thinner, etc. is spilled. Newsprint or brown packing paper that can be dispensed from a roll is a good solution.
Finally, if mixing ink and cleaning up in an area away from the printing press, invest in a wheeled cart that can accommodate the clichés, ink cups, tools, plunger can, tissues, etc. These are great for wheeling everything to and from the press from the ink mixing/clean up area without having to make multiple trips. Additionally, the carts help prevent the spills that invariably will happen when people are trying to carry all of this stuff around.
People and time: Dedicate the right personnel and adequate time for training.
Too often it is unclear which personnel are supposed to be trained and when. If the facility is new to pad printing and/or has a manufacturer that provides training in its facility, it typically is a good idea to go to the manufacturer’s facility rather than having the technician visit for the initial training. This is true for two reasons.
- The manufacturer has all of the “stuff” necessary on-hand. The tools, supplies and facilities are available to maximize training time. No time is lost running all over the shop or visiting the nearest hardware store or Grainger to purchase the supplies mentioned in this article.
- The operators receiving training can focus on the instruction without being constantly distracted with the “normal” requirements of their job.
Not everyone has to be included in training at the manufacturer’s facility. In any organization, someone has to be willing to accept responsibility for the success of the pad printing department. Someone has to “take ownership.” That person is the one who needs to attend training at the manufacturer’s facility. Maintenance personnel don’t need to visit the manufacturer for training unless complicated automation is being purchased. They can be trained in conjunction with the installation.
If only in-house training is available, limit the number of people being trained to no more than four per shift. Beyond that, a trainer cannot adequately interface with the operators to give them enough one-on-one, hands-on time to become comfortable.
If dedicated operators aren’t already in place, choose people who have exhibited the ability to follow directions and are conscientious. In initial training, personnel need to be able to focus and follow directions. Later, once they’ve gained enough machine time to become proficient, they may revise the trainer’s process to work within their own shop. That’s fine. I realize that my methodology isn’t right for everyone… and, as long as shop personnel can revise the process in a logical manner, document the revisions and teach someone else to perform them, revisions won’t result in bad habits that negatively impact efficiency and productivity.
John Kaverman has a degree in printing technology and decades of experience in process, applications and pad printing systems engineering. He has written extensively for Plastics Decorating and other industry-related publications and organizations and has authored two books on the pad printing process. Kaverman is the head of Pad Print Pros and can be reached at 517.467.5340 or www.padprintpros.com.
Installation and Training Checklist
Maximize the effectiveness of machine installation and training with this checklist.
- __ Adequately sized
- __ Clean
- __ Organized
- __ Ventilated
- __ UV-free (cliché-making only)
- __ Power (voltage, phase, plug configuration)
- __ Air (regulators, hoses, fittings)
- __ Allen/hex wrenches
- __ Screwdrivers or drill
- __ Pliers
- __ Vice-grips
- __ Digital scale
- __ Disposable cups
- __ Disposable stir sticks
- __ Solvent-resistant gloves
- __ Disposable pipettes or thinner dispensing bottles
- __ Cleaning tissues
- __ Plunger can
- __ Fireproof trash can
- __ 4×6′ table(s)
- __ Stainless steel or covered work surface
- __ Wheeled work cart
People and Time
- __ Initial training at manufacturer
- __ In-house training
- __ Ownership of the process/correct personnel
- __ Dedicated time/distraction-free