The PCB industry continues to evolve with ever increasing demands for efficiency and manufacturing cost reductions. From the design phase onward, suppliers and contract manufacturers are being asked by their OEM overlords for increased performance at lower and lower costs. An obvious potential source for cost reduction is the use of alternative cheaper raw materials or their elimination where possible. At some point in the discussion, it is sometimes asked, “Why don’t we just eliminate the conformal coating?” or "Are conformal coatings necessary".
The conversation then continues with an evaluation of the cost of materials and manufacturing involved in conformal coating the PCB design in question. Although usually a very small percentage of overall costs, often as little as one or two percent, the complete elimination of conformal coating in large volume designs could lead to savings in the thousands of dollars yearly.
So why don’t we (or you) just eliminate the conformal coating from your design? We believe the common -- and above described -- analysis is fatally flawed. It is focused around the wrong question. The question is not exclusively what does it cost to conformal coat. With just a one word addition to that sentence, we would like to discuss and present to you some thoughts on,
“What does it cost NOT to conformal coat?”
The potential costs to consider when you do not conformal coat include
- cost to repair,
- cost to replace,
- cost to reputation, and
- cost to future business.
Small and Fleeting Savings
In past discussions, we have explained the methodology for calculating the cost per board of materials for conformal coating. Without repeating that process here, a reasonable estimation is that a typical 5-inch by 5-inch PCB might require between $.03 and $.15 of conformal coating material. This is of course dependent upon the thickness of the coating applied as well as the specific chemistry of the coating, such as silicone, acrylic, polyurethane, or UV curable.
Coating Cost Per Board= Pennies (Typically)
Compare the dollars above to the overall cost to produce your PCB. There is clearly a wide range in this regard, but it is fair to say that boards in applications such as automotive and white goods where conformal coatings are typically used can be from the tens to even hundreds of dollars per PCB. As a result, the cost of coating as a percentage of your production costs can be in the single digits. In addition, any savings realized by minimizing or eliminating coating is strictly one time, never to be repeated. In the search for continuing cost reductions, elimination of conformal coating results in small and fleeting benefit at great risk.
Related Article: Conformal Coating Quality + Reputation = Reliability for Your PCB
The Risks
A list was provided earlier of the categories of risk involved with not conformal coating your PCBs. Here are a few more details and specifics of what this can entail in the quest for pennies in savings:
- Cost to Repair
Whether field repairs or warranty returns, labor and new materials will almost certainly run from tens to hundreds of dollars per repair. A warranty repair on a brake ECU as an example would certainly be in the hundreds of dollars.
- Cost to Replace
Similar to field repairs, and in fact far more common. In most cases it will be cheaper to replace the PCB in field or return. Costs again will be in the tens to hundreds of dollars.
- Cost to Reputation
Check with your accounting members. What is the value on the books for your brand name? What do you as a consumer think of products and companies that produce unreliable or failing products? Unlike savings, this loss of reputation is not a one-time cost but repeats itself for years to come and sometimes forever.
- Cost to Future Business
Studies show that the cost of reacquiring a lost customer can be as much as five times the cost to retain an existing customer. In fact it is likely even more since in critical industries such as automotive and aerospace there may in fact be no amount of money that will bring back a customer lost to failures.
In answer to the original question, "YES" conformal coatings are necessary.
As a supplier of electronics protection polymers and coatings, Chase Corporation and our employees can help you with an unbiased approach to evaluating your application and process. We’ll show you how to maximize efficiency, minimize cost, and improve product reliability. Our outstanding manufacturing and technical support groups can provide your organization with reliable global supply, unmatched quality, and superior technical support.
Please contact us today to discuss your application.
