How to choose the right color for your next powder coating project?
November 20, 2024I wrote an article about the quality control (QC) tools that every powder coater should consider using in their custom coating operation. You can find it here.
That was a fun article to write since I love gadgets, and the more QC tools I can play with, the better. This article is a continuation of that one, but is on the more serious, responsible side.
I would love to have an article rolling out the next great QC tools for powder coating, but instead I feel the responsible thing to do is to round out my first article by focusing this one on documentation and record keeping.
Sorry — there is absolutely no way to make this sound as cool as writing about a Bluetooth enabled DFT gauge hooked up to a smartphone that syncs to the cloud automatically with photos attached. But if words like verifiable, quality, and risk management give you pause, then read on.
What data to track
When looking at the data that we should track, I am inclined to break it up into two categories. The first category is what you should be tracking all the time. The second is what you track because your customer has specific requirements. This is by no means an exhaustive list, and there may be things that you do or do not track all the time because your processes differ from mine. That’s fine. As long as the data that you keep has some use, then more power to you.
Tracking all-the-time data
This data is useful because it can bring clarity to the production team on the floor, ensure quality processes are being followed for future verification, and provide useful business intelligence to your company.
Receiving report. For every order that comes in the door at our business, a clear product photograph is taken and product dimensions are recorded. This enables us to communicate effectively to the floor on what everyone should be looking for at the various stages of the finishing process.
In our shop, there are varying degrees of comprehension when it comes to written English. Providing our employees with clear photos of the product they are working on saves time through the elimination of questions and guesswork.
Another benefit of having photographs of everything that comes into our shop is the ability to point to the condition of goods when they arrive. On a few occasions, customers have questioned where goods were damaged. By having clear pictures, we have been able to provide them with not just our word, but evidence after the fact.
Last but not least, photographs also allow us to mark up the products digitally where masking and key instructions are concerned.
Work order. From the receiving report, we create a work order (WO). This document communicates the who, what, and how of processing the job on the floor. For the purpose of this article, the most important information that is provided on the order are the WO number (which is used to link the receiving report and all other data that will be covered in this article), the surface preparation requirements, base coat, top coat, and time and temperature requirements.
This document is also used to communicate any special instructions to the floor that may be out of the ordinary (i.e. mask machined surfaces, coat one side only, etc.) as well as the total quantity of specific items for the order.
Rework. Yup — it sucks. And that is why you should track it. As soon as nonconforming work is detected on the floor, we photograph and document the issue, being careful to identify the reason for the rework, the action we took to fix it in the moment, and the proposed corrective action to take in order to avoid it in the future.
Unless your customers require you to have a certified QC system such as ISO, you have the opportunity to make this as simple and effective as possible. The addition of photographs to the rework report makes it easier to point out exactly what went wrong and why.
The key to this type of data is that it must be used in a timely manner. Reviewing the data a month after the issue occurred will not be as impactful as reviewing it the same day or the day following the incident.
Time and temperature. In our plant, we track the processing time for our main profit centers: blast booth, coating booth, and oven. This is useful for ongoing performance monitoring and establishing costing for unique jobs. From a data tracking standpoint, tracking oven time takes on a quality aspect in the production process.
Custom coaters encounter a variety of shapes, sizes, and substrates when processing jobs. By keeping a record of the time and temperature for jobs as they move in and out of the oven, we are able to reasonably determine whether a product was cured or not.
The caveat here is that in order to verify with confidence, the substrate should have a thermal profile run using one of the commercially available oven data loggers. Afterwards, a simple MEK test can be run as a qualitative go/no-go to check the cure.
Material. Assuming that you have properly cured the powder onto the substrate, the next best thing to track to avoid potential issues down the road is the powder batch.
Every box of powder should have a batch number. The batch number links the box of powder to the production run that it was made on. By linking this number to the specific job that you are working on, you are ensuring that if anything goes wrong with the job in the field, you can provide the batch number to your supplier and they can check the original powder in their facility. My hope is that you never have to resort to this degree of verification. However, from my personal experience, keeping this record has saved me thousands of dollars on one single occasion.
Titration log. While we do not run chemical tanks or a spray line at our plant, there are many custom coaters out there who do. If you do, this is a log that you should keep in order to ensure that your chemistry is doing what it should in regards to cleaning and pretreating customers’ goods. If you do not have one in place now, your supplier is the best person to engage in getting a program set up for you.
Tracking job-specific data
Job-specific data tracking is useful if your customer has specifically requested it as a condition of performing the work or if you are part of a special coating program (automotive, architectural, OEM, etc.) that requires you to keep specific logs.
DFT records. Dry film thickness (DFT) records provide you and your customer with verification that the target film thickness has been achieved. Depending on the requirements of your customer, this may be as detailed as a certain number of measurements per part or a random sampling throughout a run. Either way, there are DFT gauges on the market now that can make it easy to track and produce reports using their report generation software.
Thermal profile log. Using an oven data logger, you are able to input the powder manufacturers cure data, run the customer’s part with probes attached, and produce a report that indicates the degree to which cure has been achieved. This is also useful at the beginning of a project for determining the best time/temperature recipe for an ongoing project to ensure cure and reduce bottlenecks at your oven.
Blast profile records. As discussed in a past article, the blast profile is integral to adhesion and lasting quality on customers’ goods. As with the DFT gauge, there will be a range that customers require for their orders.
Worth a look
Apart from QC tool-specific software, we only use two programs in-house to keep track of all our documentation. The first is our ERP package, which tracks orders from the quote stage all the way through to billing. The second is a free application called Evernote that can be run on your desktops, smartphones, and tablets. Evernote easily replaced the time-consuming process of taking a picture with a digital camera, removing the chip and placing it in a desktop, copying the picture to a Word document, printing it, and affixing it to our WO. The title of the note reflects the WO number, and all of the data is stored in the cloud so you can literally call it up from anywhere. The only other application that is similar is OneNote; however, Evernote proved to be the simpler option for our process.
Make it flow
With some planning and trial and error, data collection can become a natural part of the processes that you run on your production floor. If you have the time, this data can even be used to create key performance indicators (KPIs) on your floor that allow you to measure your team and individual operators’ performance (i.e. profit center utilization can be determined based on available booth time versus billable use time). Be sure to track only that which has immediate or long-term value, and work with your team on the floor to make it as pain free as possible. If your team is spending even 10 percent of its time filling in time cards in a given day, then they’re not being productive. By making your data collection flow and tracking the right things, your business will benefit from greater protection from long-term risk and insight into your productivity on the floor.