If you’re reading this, chances are that you are still involved in some type of finishing work

In short—you’re still manufacturing. We are all faced with pricing pressures, just-in-time deliveries, and overall increasing overhead costs. Add to that the globalization of manufacturing and the playing field just doesn’t seem that level here at home.

“It’s just too expensive to maintain our finishing operations here—we’re shutting down this product line and moving it off shore. We just can’t compete anymore.” I’ve heard that on a time or two in my travels.

While one can understand the frustrations and pressures we face as North American manufacturers, the above statement is shortsighted and often is the easy answer for a lot of us. Don’t get me wrong—there are certainly disadvantages for us when competing in a global economy. It is, however, your choice, whether you choose to be thriving, dying, or are soon to be dead.

Continuous Development
Are you still performing your finishing operations the way you were 10 or even five years ago? Sure, it takes time to develop a process. But if you are not continuously improving, refining, and re-developing, you’re going to be passed by someone who does. Here’s an example:

Company ABC produces plumbing fixtures and polishes them using a combination of manual buffing jacks as well as some 1970s rotary buffing machines. They have their process down pat—they can produce more than 1,000 pieces per hour with minimal rejects. They have developed a process using a cut/color compound with a combination of sisal and cotton buffing wheels. They apply their compound with several traditional air-operated spray guns. This equipment is operated by three hourly workers who load, unload, inspect and visually check the proper operation of the equipment throughout the day. This company is located in Jonesville, USA.

Company XYZ produces similar items as company ABC, as well as some additional items. They have recently invested in an indexing rotary table, as well as several robotic cells, lower volume items, as well as increased flexibility. They have installed a state-of-the-art dust collection system as well as liquid compound distribution system. This equipment has been in production for three months. Each month different combinations of buffs and compounds are tested during production time in order to optimize performance of this system. Investment was approximately $1 million. This company is located in China.

Yes—China.

The point of the above example is to dispel the common notion that we (North American manufacturers) believe we are losing a battle to low cost labor. This is simply not the case. While labor is somewhat of a hurdle, the above example shows that our overseas competitors are placing a premium of quality, flexibility, and price.

So what can you do about this? Let’s start by taking a look at equipment options.

Figure 1. Robotic cell using two (2) ABB robots and rotary carousel magazine for unattended operation. Note the articulated movement, which allows processing of multiple surfaces to be processed.

Machinery
There are many equipment choices and optional features available today. Yes, rotary tables or in-line systems might make sense in some applications, but what do you do when you’ve suddenly been given orders for several different items in small batches? Enter the robotic cell.

Robots can be configured with combinations of belt polishing as well as buffing stands. Installed with magazines, they can run unattended for entire shifts. Figure 1 shows such a system which can be equipped with lengthy belts and large diameter buffing wheels to minimize changeovers due to consumable wear. Electronically controlled sensing systems that measure wear of consumables lead to greater accuracy as well as easier programming for operators. Dependability has improved ten-fold through the years.

One word of caution when considering a robotic buffing and polishing system: Look to those vendors who specialize in buffing and polishing. I’ve heard countless stories at tradeshows of companies that have either used an existing robot from their facility and try to incorporate it into some type of buffing jack. Usually they are doomed to failure from the start. In addition, make sure the system has a well proven feed-back device. This makes for both easier programming/set-up, as well as improved consistency in finishing results.

Hybrid Robotic/Rotary System
Relatively new in the field, this type of equipment couples the potential high productivity of a rotary table concept with the flexibility of multi-axis heads placed around the rotary table. These can be configured with 1–12 stations.

Both flexibility and productivity are offered via 3–4 axis programmable heads coupled with an indexing rotary table. Options include automatic tool (buff) change, on-the-fly part/program change, and a host of other possibilities.

Note the articulated movement – allowing for multiple surfaces to be processed.

A good example of this type of system in use would be a wheel manufacturer as shown in Figure 2. In the past, wheels were typically processed on rotary tables, which consisted of many stations. While such systems are highly productive when running, downtime due to changeovers is extremely high. A robotic cell offers extremely high flexibility, but is simply not as productive as a rotary system. This is where a hybrid robotic/indexing table can pay huge dividends. This is not only true for items such as wheels, but in addition may include water fittings, sinks, and other products with multiple surfaces to be buffed.

The previously mentioned systems are but one of many types of systems that are currently available today, and may or may not fit your particular method of manufacturing. The point is not to recommend any one type of system, but rather to encourage you to explore the possibilities available today—after all, your competitors are.

Consumables/Application Systems
As mentioned earlier, the example of company XYZ illustrates the continuous improvement concept. While sounding straightforward, it’s not. Companies have worked months—even years—developing processes that work for them. It’s easy to get comfortable with your process—it works, doesn’t it? But if that theory were followed by everyone, we wouldn’t have new buff technology, non-woven products, coated abrasives and other advances. Set aside some time each month to try a new consumable—you might be surprised what you find. Your vendors are continuously developing new products, and if you don’t take advantage of them, someone else will.

Application System: A critical Component
Another factor in buffing and polishing is the application system. This is looked at by many as a small part of the equation, but in reality it is perhaps the most critical factor for a couple of reasons:

First, you may have the greatest piece of equipment in the world, outfitted with the best buffing wheel/compound money can buy. But if you can’t apply the compound to the buff properly, it doesn’t matter.

Second, if you’re not using some type of automated application system, you’re wasting valuable time for your actual production. In a manual polishing operation, this is especially true. Having operators stop and apply compound by hand after every 4 or 5 pieces cuts dramatically into that rates. Imagine the productivity gained by equipping that manual buffing jack with an automatic compound distribution system, which is available for both liquid and solid compound.

As far as spray systems are concerned, there are two basic types: low pressure and high pressure. Depending on the application, one or the other will work best.

For operations that use relatively low wheel surface speeds, a low-pressure system will lend itself just fine. These types of spray guns are essentially “solenoids” that spray a large volume of compound when opened.

Figure 3. Example of a high pressure spray gun using a remote extension tip. This is very useful in manual buffing systems, as well as getting into tight areas where mounting the entire gun body can be difficult.

The length of the spray cycle will determine the amount of compound distributed. The advantages of these types of guns are the low initial investment as well as ease of maintenance and relatively low spare parts costs. The disadvantage is the large amount of compound usage/overspray, as well as the overall inefficiency of the application of compound where it needs to be.

High-pressure systems offer spray pressures of 2,000 psi and beyond. The Widoberg/Widospray types generate high pressure within the gun using normal shop compressed air. Figure 3 shows an example of a high-pressure spray system. In addition, the exact volume of compound can be metered with each spray cycle.

The major advantage of this type of spray system is that it can penetrate the wind barrier created by the buffing wheel, meaning more compound will be delivered to the buffing wheel. Savings of 50% or more in compound consumption can be achieved.

The disadvantage of this type of system is the high initial investment cost as well as high maintenance costs. Whether you operate a fully automated polishing operation or a small job shop, there is always room for improvement. There are many choices of equipment and methods available in the market today. And the point here is to open your eyes to the new possibilities that you may have been missing. We must invest in the future if we expect to be able to compete in the new global economy. PFD