The Importance of Machine Approval

by John Kaverman, president, Pad Print Pros
Photo courtesy of Pad Print Pros

The importance of machine approval at the manufacturer’s facility often is ignored due to timing or budgetary constraints. This is unfortunate, because neglecting to conduct a thorough approval can end up costing a lot more time and money than what was saved by not traveling to the supplier to approve the machine before it shipped.

True, for those who’ve printed before and are just buying a simple machine without any application-specific tooling, options or accessories, it might be possible to get away with forfeiting the approval. But even then, for those not familiar with all of the features of the new machine, end users may utilize only a portion of its features and production capacity.

Modern pad printing machines have evolved in the past two decades: Programmable electric motors have replaced pneumatic drives; multiple axis part conveying has significantly reduced the number of set-ups required; on-board memory has minimized changeover times; and the list goes on.

It is highly recommended that buyers consider conducting a thorough approval at their supplier’s facility if they are purchasing a new piece of equipment when any of the following is included in the scope of the project:

Part-specific tooling

Regardless of whether buyers are purchasing part-specific nesting fixtures or jigs with a new system, or making them themselves, it is imperative that they ensure it all works as intended. This is especially true in applications where multiple versions and rapid changeover of part-specific tooling are required.

Fixtures need to be easy to load and unload without interfering with mechanical or photo-electric safety barriers and must accurately locate production level parts for processing throughout the entire cycle. Once the machine is in the facility, it is too late to say, “Oops, we wanted the part in this orientation.”

Obviously, if buyers are making the nesting fixtures, they need to share their plan for orienting the part on the system so the supplier can orient the images correctly on the clichés. Additionally, buyers need to be prepared to ship their tooling and an adequate number of production-level parts to the supplier’s facility for use during the approval.


If pre-treatment equipment (plasma, corona, flame) is being integrated, buyers will want to verify that the results of the pre-treatment are within specification for required dyne level. Treatment area dimensions, offsets (distance from the treatment head or flame ribbon to the surface of the part), travel (when the pre-treatment has to actuate) and treatment (dwell) times all need to be addressed. Assuming the supplier has all of the necessary components and tools required to make any revisions, it is easier to do it with the buyer standing there than to try to coordinate it all over the phone.


Drying and curing equipment needs to be verified to ensure it attains the desired level of adhesion, as well as mechanical and chemical resistance for the printed image.

In the case of either pre- or post-treatment equipment, buyers must also ensure that their production representative parts are clean (not contaminated), and that the ink has been mixed, applied (i.e. cliché depth recommendations), dried and cured per the ink manufacturer’s recommendations. After all, if the ink wasn’t mixed correctly, was applied to a contaminated part using a cliché that was the wrong depth, and the ink wasn’t allowed to complete its chemical/physical curing schedule, the result can’t be blamed on the pre- and/or post-treatment equipment.


On-site approval for automated systems is essential. Automation involves programming of either proprietary controls or commercial programmable logic controllers (PLCs) to synchronize loading and unloading, pre- and post-treatment, as well as part conveying accessories and, in some cases, the printing cycle itself.

Conducting an approval at the supplier’s facility can catch little programming glitches that might otherwise be missed during the supplier’s standard de-bugging. Once the system is in the facility, revisions to programs can be difficult, especially when the printer has proprietary software.

Remote location

Photo courtesy of Pad Print Pros

When the facility is in a geographically remote location, service by the supplier’s technician can be extremely expensive. For example, an installation was done in Michigan’s Upper Peninsula, where the nearest airport had one flight in and out per day, and the nearest big box hardware store was two hours away. Luckily, that customer visited the manufacturer’s facility for a thorough approval weeks before the machine was due to ship to their facility. While the revisions that were identified as being necessary during the approval were simple to complete in the facility, they would have been significantly more difficult to make once the machine was in the buyer’s plant.

Who should attend approval?

The decision of whom to send to the supplier’s facility for approval is an important one. There is little benefit in sending people other than those who:

  1. Know what is expected of the machine in production. System throughput and image quality need to be addressed. That doesn’t mean buyers need to send an engineer, an operator and a representative of their QC department. It simply means the person attending the approval should be knowledgeable of the requirements.
  2. Can understand the electrical and mechanical functions of the machine. Again, this doesn’t necessarily mean having to have someone from engineering and maintenance in attendance, but buyers should endeavor to send someone with basic electrical/mechanical aptitude.
  3. Have at least a functional knowledge of pad printing. If buyers are combining approval with operator training, they need to send an operator or at least someone qualified to train their operators once the system is in their facility.
  4. Are empowered to make a final decision. The person attending approval doesn’t need to be a member of management but should be able to communicate effectively with management while on site.

What to bring to approval

The person or persons attending approval at the supplier facility should bring a digital camera or smartphone to take photos and video of the machine, the printing cycle and the resulting printed product. They also should bring quality, production representative samples (if they exist) for comparison, as well as master color samples for when custom colors are part of the package.

Alternatives to approval

In a perfect world, buyers have the right person, the time and the budget to make the trip to their supplier for a thorough approval. But, what do they do if/when their pick for approval has a scheduling conflict or they’re having difficulty justifying the cost of the trip?

First, consider the potential cost of not sending someone for approval. How tight is the timeline? Is it better to sacrifice a day or two for the technician to visit the supplier for approval, or potentially lose several days (or weeks) of production if the machine arrives and something isn’t right?

If buyers are convinced that for some reason they can’t justify sending someone for approval, make a list of all of the points the supplier needs to address before the machine ships. Ask the supplier to go over the list point by point, preferably on video. Ask for photos and video of the system functioning and/or physical samples of the printed product for evaluation for making the decision to ship.

Get trained

Regardless of whether buyers elect to conduct a thorough approval at their supplier’s facility, they should not neglect to obtain adequate training.

Assuming buyers are sending someone with the technical aptitude required, training can be conducted in conjunction with the approval. That person doesn’t need to be the operator but should be able to go back and train the operators. Recording the training on video is always useful.

When not conducting approval at the supplier’s facility, have the supplier travel to the buyer’s facility for installation and training.

Skipping both the approval and training is a huge gamble, unless all that’s being purchased is a duplicate of a system that already exists in the facility. Even when switching from one brand of equipment to another, there are going to be features on the new machine that might go unnoticed without training. Get trained to ensure that the new machine is being utilized to its full potential.


The importance of machine approval (and operator training) cannot be overstated. This is true for pad printing machines, as well as any other type of decorating equipment.

John Kaverman is president of Pad Print Pros LLC, an independent consulting firm specializing in pad printing. Kaverman has 28 years of combined industrial screen and pad printing process experience. He can be reached via email at or through his website,