How To Mask Mating Surfaces

Masking off mating surfaces can be crucial for maintaining a smooth surface that is optimal for sealing, grounding purposes, bearing surfaces, and countless other reasons you'd want a clean mating surface.? By protecting the surface integrity, you maintain dimensional accuracy and avoid secondary operations, which improve line output efficiency and decrease operational costs.

If you're reading this post, you likely already know WHY you need to keep mating surfaces clean, so let's get into HOW to mask off mating surfaces!

Masking Tapes and Die-Cuts

One of the most common methods for masking off mating surfaces before coating the parts is by using masking tape. This is typically done in one of two ways:

Die-Cut Masking Tape

Die-cut tapes are simply pre-cut shapes or patterns designed to mask off specific areas. Die cuts will speed up the masking process (compared to manual cutting), improve quality, and reduce the risk of injury.

Things to Know:

• Basic die-cut shapes (circles, donuts, squares, and rectangles) can typically be purchased without additional design or tooling.
• Some metal finishers use in-house plotters to die-cut shapes as needed using masking tapes sold on liners. (Example: Green Poly on Liner )
• Ensure the masking tape material can withstand your curing oven's temperature.

Masking Tape (Manually Cut)

For job shops with low-volume projects, we recommend using rolls of masking tape and, when needed, an X-Acto knife to cut off the excess tape. This method is not recommended for mid- to high-volume runs but is great for one-off projects.

Custom Rubber Masking

For mid- to high-volume production runs, we suggest looking into custom masking solutions made of high-temperature silicone. Molded masking parts allow you to quickly and easily install and remove the masking with high consistency, reducing labor costs and quality issues.

Check out a few of the examples below of custom silicone masking products we've designed and manufactured to mask off different types of mating surfaces.

Magnetic Masking

An issue with using a rubber-molded part to mask off a mating surface is that you need something to cap onto or plug into. In some cases, you might not have one of those options. For these kinds of situations, we recommend considering magnetic masking.

Magnetic masks can not only withstand high temperatures, but they're much faster to install and remove, saving you countless amounts of time compared to most of your other options.

Learn More About Magnetic Masking

Conclusion

These methods are some of the most commonly used ways to mask off mating surfaces effectively. With that said, there are still other methods that metal coaters use to maintain a clean mating surface. A few of the alternative methods we've seen include:

1. Powder coaters that wipe/vacuum the powder off before the curing process.
2. Using a metal plate/bolt combination rather than masking tape or molded mask
3. CNC machine the surface
4. Using masking tape in combination with aluminum foil to mask off large surfaces

At the end of the day, sometimes you have to do what gets the job done. If you're looking to improve your masking operations, are running into any masking issues (such as leakage or powder buildup), or want to try out some samples, please fill out the form below. Our team will be more than happy to see how we can help!