Powder coating is a high-temperature coating process that requires specialized materials and equipment. Because of this, we get a ton of questions from not only new powder coating lines but also some of the most well-known brands that have the most advanced paint lines we've ever seen.
So, we've created this new list of frequently asked masking questions below to help you out. The goal here is to answer the questions you may have. If you don't see the question/answer you're looking for, let us know. We'd love to hear from you and continue adding to this list as a resource for powder coaters everywhere.
What Tape Should I Use?
When it comes to choosing a tape for powder coating, the biggest factor you need to consider is temperature. The primary masking tapes you're gonna see most often are polyester tapes and glass cloth tape. Below is a quick view of the most popular options:
Green Poly Tape
Blue Poly Tape
Glass Cloth Tape
What Material Is Used For Masking?
When it comes to masking during powder coating, the most commonly used and most effective material you'll see is going to be silicone. Why? Because silicone has excellent heat resistance and can withstand temperatures up to 500F!
To be even more specific, you'll typically see expert masking suppliers use a peroxide-cured silicone that is put through a high-heat post-curing system that accelerates and removes residue, odor, and toxins, as well as improving the characteristics of the materials.
How Can I Speed Up Our Masking Process?
Speeding Up Taping Process
If you're using rolls of masking tape, such as green poly, you can speed up your masking process by switching to custom die-cut tapes. The worst part of using masking tape tends to be from having to carefully apply and cut to specific shapes. Die-cuts takes the cutting process out of it and saves your line countless hours
For faster removal, we suggest adding some form of a pull tab.
Custom Molded Masking
Custom molded masking solutions are silicone masks designed and manufactured for custom applications, such as masking a specific wheel hub or shock tube. These are used by mid-to-high volume paint lines that require tight tolerances and fast production speed times.
How Do You Mask Threaded Holes?
The easiest method of masking a threaded hole for your powder coating process is by using a silicone masking plug. There are a variety of different types of masking plugs, both catalog and customer, that you can choose from. The two most popular options for powder coaters are going to be tapered plugs (for blind holes) and pull plugs (for through holes).
Silicone Tapered Plugs
Silicone tapered plugs are designed to be pushed into threaded holes. The tapered design gives them the ability to mask a small range of different-sized holes.
Silicone Pull Plugs
Silicone pull plugs are designed to mask off threaded through holes, ensuring both sides of the threaded hole are masked off. These plugs need to be slightly oversized to create an effective seal.
How Many Times Can I Use a Cap / Plug?
One of the benefits of silicone's high-temperature resistance is that in many cases it can be reused before having to dispose of them. Unfortunately, when it comes to this question, there is not a one-size-fits-all answer. Typically, our customers have reported that they're able to get right around 10-20 uses out of them before they toss them out.
If you're unsure how many times you will be able to use them before making a purchasing decision, we recommend testing samples out to see how they perform. The major factors that will contribute towards a masking cap or plugs longevity include:
- Curing oven temperature (the higher the temperature will result in less reusability)
- Time in oven
- Cleaning method of the cap/plug
How Do I Prevent Powder Build-Up Around Masking Caps and Plugs?
Paint buildup typically happens because when it hits the masking cap or plug, resulting in buildup around the mask itself.
One of the most efficient solutions to help reduce bridging is to implement a custom mask that provides protection around the grounding area of the transitional spot. There are several designs to achieve this protection, but a common solution is to design a mask with a flange wrapped around at an angle like an umbrella or a skirt.
Can I Hang My Part Using the Masking Component?
This question is geared directly towards using a masking cap or plug to hang a component without interfering with grounding. The only way you're able to effectively do this is by using conductive silicone. This a material that is created by adding carbon black to the silicone, making it conductive, giving the mask the ability to act as the grounding point.
What Other Questions Do You Have?
We know that this list is just a fraction of the questions out there when it comes to masking for powder coating. What would you add to this list? Let us know by contacting us today and we'll see what our engineers have to say.