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Materials & Coatings
When your project requires high-performance hardware with tight dimensional tolerances, standard thick platings are not always an option. Black oxide coating is a specialized chemical conversion process that converts the top layer of a metal into a naturally occurring, protective black iron oxide.
Since 1988, U-Bolt-It has provided high-quality, certified-engineering coating services. Our in-house black oxidizing process delivers a clean aesthetic finish with minimal change to thickness—adding as little as five millionths of an inch. This ensures precision fasteners retain their exact sharpness and strength without increasing brittleness.
When treated with an after-finish, such as oil or wax, black oxide fasteners offer incredible dependability in mission-critical systems. This budget-friendly alternative to heavy plating offers several key advantages:
During the black oxide process, our engineers pay careful attention to temperature, chemistry, and processing times to produce uniform coverage. We apply this coating to a variety of metals, including stainless steel, carbon steel, and non-ferrous metals like copper. (Note: Black oxide cannot be produced over plated parts; existing plating must be stripped prior to processing).
We offer black oxide processing for both large batches and short custom runs, including:
Because this finish meets such strict dimensional and aesthetic standards, we regularly supply black oxide hardware to the following industries:
Unlike paint or zinc plating, which adds a physical layer on top of the metal, a conversion coating chemically reacts with the surface of the metal itself. Black oxide changes the top layer of the fastener into magnetite (black iron oxide), ensuring the coating cannot easily chip or peel off.
No. One of the primary reasons engineers choose black oxide is its dimensional stability. The process alters the thickness of the part by as little as five millionths of an inch, making it ideal for precision threads and tight-tolerance assemblies.
By itself, black oxide offers mild corrosion resistance. However, its slightly porous nature makes it an excellent absorbent for after-finishes. When treated with an oil or wax sealant after the chemical bath, its corrosion and abrasion resistance is significantly multiplied.
We don't just coat hardware; we manufacture it. Because we understand the critical engineering behind the fasteners, our team ensures the temperature and chemistry of our in-house black oxidizing process are perfectly calibrated for your specific material. Contact our team today to get a quote on your next batch of premium coated fasteners.
"We feel really happy working with you guys, it has been a short time business relationship but definitely we’ve received such a great service from your company that would be nice to keep working together. Junior is our contact point and there’s nothing but great things to say about his attentions. By the way, I truly loved the microfiber cloth. I’m always have a hard time to clean my glasses; I can use the one from U-bolt it without applying any liquid and just leaves them super clean. We appreciate your excellent service and looking forward to new projects. Kind regards and have a wonderful rest of the week."
"Our buyer received a letter from your company regarding an order I put in for some 3” stainless steel U-Bolts. I just wanted to thank you for the kind letter and let you know that your U-Bolts have been completely invaluable to us. We use them in the manufacturing process of an extremely sensitive product. Our previous U-bolts were zinc plated, therefore they became rusted too easily and risked the quality of the product. We hadn’t been able to find another U-bolt supplier with our specific size requirements (without going custom) until I came across your website! We are very grateful for the quality product you have sent us. We will definitely continue to use your company and the services provided."
"Debbie here from KKW in Mukwonago WI, just got the big u-bolts they look real good. They should work good for my project."
"I wanted to say how helpful it was to be able to order small quantities of screws from your business. As a start up business, without an established presence, it is virtually impossible to get small quantities of screws as samples. When we go into production, we will be ordering millions of screws, but we need to know that the same screws we test with our prototypes will be available at bulk prices at that time."
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