How to Stop Flash Rust with Rustbuster Bor-X
You’ve just blasted or washed a panel back to bright, clean steel — and within minutes it’s turning orange again. That sudden corrosion is flash rust, and it’s the bane of every restoration and paint prep. Rustbuster Bor-X stops it: a water-soluble corrosion inhibitor you add to your wash or rinse water, so freshly cleaned steel stays clean and rust-free until it’s dry and ready to paint.
What is flash rust?
When bare steel gets wet during blasting, rinsing or cleaning, it can corrode almost instantly — a bright, clean surface turning orange within minutes. It’s more than just annoying: flash rust means re-doing prep you’ve already finished, and even a light film of it left under paint weakens adhesion and shortens the life of your coating. It’s especially quick to strike on freshly cleaned ferrous metal after any wet process.
How Bor-X stops it
Bor-X is a high-performance, water-soluble, multi-metal corrosion inhibitor, and it works in three simple steps:
- Mix it in — add Bor-X to your rinse, wash or cleaning water at a low concentration.
- It bonds to the metal — the inhibitor forms a short-term protective barrier at the surface, blocking the oxygen and moisture that cause flash rust.
- It dries clean — the metal stays rust-free as it dries, ready for painting or coating.
How to use Bor-X
Clean the surface first
Bor-X protects clean metal — it isn’t a cleaner. Wash off oils, grease and salts first (see our surface preparation and salt removal guides).
Mix it into your water
Add Bor-X to your rinse, wash or cleaning water at the recommended low percentage — no special equipment needed. It’s worth testing on a small part first to dial in the right concentration.
Treat the metal
Wash or rinse the steel with the Bor-X solution. The inhibitor bonds at the surface, blocking the oxygen and moisture that cause flash rust.
Dry, then paint
As the metal dries it stays clean and rust-free — a well-keyed surface ready for primer or coating. Prime it before fresh contamination has a chance to settle back on.
Where it helps
- DIY classic car restoration
- Home restorers & hobbyists
- Small workshops & fab shops
- Metal prep before painting
- Handling & storage between stages
- Added to metalworking fluids
Whether you’re restoring a classic, prepping steel for a fresh paint job or running a busy workshop, Bor-X takes the stress out of those sudden orange rust spots. It’s supplied as a 20L concentrate that goes a long way at its low dose rate.
Bor-X FAQs
What is flash rust?
Flash rust is the rapid, light-orange corrosion that appears on bare steel within minutes of it getting wet during blasting, washing or cleaning. A bright, clean surface can turn orange almost instantly — ruining your prep and hurting paint adhesion.
How does Bor-X prevent flash rust?
Bor-X is a water-soluble corrosion inhibitor you add to your wash, rinse or cleaning water. It bonds at the metal surface and blocks the oxygen and moisture that cause flash rust, so the steel dries clean and rust-free, ready to paint.
How do I use Bor-X?
Clean the metal first, then mix Bor-X into your rinse or wash water at a low percentage — test on a small part to find the right rate. Treat the surface, and let it dry rust-free before you prime or coat.
What can I use Bor-X on?
Mainly ferrous metals such as mild steel, during restoration, paint prep and workshop handling. It’s also used as a multi-metal corrosion inhibitor in semi-synthetic and fully synthetic metalworking fluids.
Flash rust is a prep problem — beat it at that stage. For the full picture see our surface preparation guide and 10 steps to complete rust protection.
