The BF-61 Hornbill is a 24cm high carbon balisong, 12cm blade, 180g, brass with kamagong. High carbon steel rusts. Here is exactly how that happens, how to stop it, and what to do when it has already started.
How rust actually starts
Iron, water and oxygen. That is the whole recipe, and plain carbon steel has no chromium in it to interrupt the reaction. Salt speeds it up considerably, which is why sweat is worse than tap water and coastal air is worse than both.
The places it starts are predictable and they are almost never the flat of the blade, which is the part people wipe. It starts in the corners.
- The choil, where the edge meets the tang. It holds a drop of water and nobody dries it.
- Inside the handle channels, where the blade sits closed.
- Around the pivot and the tang pin.
- Under a fingerprint that was left on overnight.
Prevention, which is eight seconds
Wipe the blade dry after you handle it. That is the requirement. Not weekly, not when you remember, but when you put the knife down.
Beyond that: a light oil film once a month, open the knife and dry the choil properly if it has been anywhere damp, and do not store it in the leather sheath. Sheaths are for carrying. A closed sheath holds moisture against steel and it is the single most reliable way to ruin a high carbon blade.
If it has already started
| What you see |
What it is |
What to do |
| Grey or blue-grey, smooth |
Patina |
Nothing. Leave it. It is protecting the steel |
| Light orange dust, wipes off |
Surface rust, caught early |
Oil on a cloth, rub firmly. It comes off |
| Orange, rough, does not wipe off |
Established rust |
Fine abrasive with oil, work gently, then oil the bare steel |
| Dark pits left behind after cleaning |
Pitting |
Permanent. The steel is gone. Oil it and carry on |
| Orange at the edge, blade feels dull |
Rust on the apex |
Sharpen it back. Do not try to polish it out |
Almost everything on that list is recoverable. Only the last row of column three is not, and getting there takes real neglect over months rather than a wet weekend.
What not to do
Do not use a wire brush, a rotary tool, or any of the aggressive rust removers sold for car bodywork. They take off far more steel than the rust did and they will wreck the finish and the geometry. Oil and a fine abrasive, patiently, is the answer every time.
Also do not panic. A grey blade is a healthy blade. Most of the emails we get about rust turn out to be photographs of a perfectly normal patina forming.
The high carbon steel, and why we still sell a butterfly knife in it
Plain carbon steel: iron, about one percent carbon, no meaningful chromium. Everything above is the price. What you get in return is the finest edge we can grind, because the grain is much finer than any stainless at the same hardness, and a steel that comes back on an ordinary stone in minutes rather than fighting you.
We heat treat to 58-60 HRC, which is where it rolls rather than chips when it meets a floor.
The frame and the kamagong balisong handle
Standard 24cm at 180g, brass bolsters with kamagong inserts. Neither the brass nor the wood will rust or rot, so the blade is the only part of this knife with an opinion about weather. Kamagong is Philippine ebony and is dense enough to ignore moisture entirely.
Ordering this high carbon balisong
The unsharpened trainer costs.00 and is selected above Add to Cart. Everything on this page still applies to it, since a blunt high carbon blade rusts exactly as enthusiastically as a sharp one.
A fitted leather sheath comes with it, with the storage caveat above. US shipping free, flat $49 elsewhere for the whole order.
Hornbill pairs high carbon steel with a brass and kamagong wood handle, and at 24cm it sits comfortably in the hand. If the latch style on this build is new to you, our guide to balisong latch types explains how it compares with the other closures we use. You can browse the rest of the rest of our high carbon steel balisongs from here, and the Horse high carbon balisong is a close neighbour worth a look if you want a second option in hand.
Luis Reyes –
Five stars isn’t even enough honestly. Great buy overall.
Samuel Ortiz –
My buddy was speechless when he tried flipping this. Latch snaps shut clean every time. Will definitely order again for another one.
Kenji Stewart –
Best butterfly knife I’ve owned so far. Highly recommend this one to any flipper. Balisong Butterfly is quickly becoming my go to shop for balisongs. You can tell real Filipino makers built this. Made in the USA and shipped fast too.
Jeffrey Reyes –
Absolutely love this balisong. Weight is perfectly balanced for flipping. If you’re on the fence just get it. You won’t regret it.
Emma Chavez –
This is exactly what I wanted and then some. Already telling my flipper friends to check this out.
Frank Adams –
Can’t stop flipping this thing honestly. Pivots feel dialed in with zero blade play. Comes with a nice pouch which is a nice touch. This is my new favorite in the collection.
Grace Flores –
Not what I paid for. Action was rough and gritty right out of the box. Arrived with noticeable blade play that a screwdriver couldn’t fully fix. Not what I expected for the price paid.
Douglas Smith –
This is exactly what I wanted and then some.
Jennifer Castillo –
Photos don’t do this knife justice at all. Pivots feel dialed in with zero blade play. Cool that these are made by actual Filipino craftsmen right here in the USA. So worth it.
Antonio Collins –
So happy I finally pulled the trigger on this one. Comes with a nice pouch which is a nice touch. Weight is perfectly balanced for flipping. This is my new favorite in the collection.
Luis Reyes –
Five stars isn’t even enough honestly. Great buy overall.
Samuel Ortiz –
My buddy was speechless when he tried flipping this. Latch snaps shut clean every time. Will definitely order again for another one.
Kenji Stewart –
Best butterfly knife I’ve owned so far. Highly recommend this one to any flipper. Balisong Butterfly is quickly becoming my go to shop for balisongs. You can tell real Filipino makers built this. Made in the USA and shipped fast too.
Jeffrey Reyes –
Absolutely love this balisong. Weight is perfectly balanced for flipping. If you’re on the fence just get it. You won’t regret it.
Emma Chavez –
This is exactly what I wanted and then some. Already telling my flipper friends to check this out.
Frank Adams –
Can’t stop flipping this thing honestly. Pivots feel dialed in with zero blade play. Comes with a nice pouch which is a nice touch. This is my new favorite in the collection.
Grace Flores –
Not what I paid for. Action was rough and gritty right out of the box. Arrived with noticeable blade play that a screwdriver couldn’t fully fix. Not what I expected for the price paid.
Douglas Smith –
This is exactly what I wanted and then some.
Jennifer Castillo –
Photos don’t do this knife justice at all. Pivots feel dialed in with zero blade play. Cool that these are made by actual Filipino craftsmen right here in the USA. So worth it.
Antonio Collins –
So happy I finally pulled the trigger on this one. Comes with a nice pouch which is a nice touch. Weight is perfectly balanced for flipping. This is my new favorite in the collection.
Samuel Kim –
Genuinely very pleased with how this turned out.
Amanda Rivera –
Feels way more premium than the price suggests. Weight is perfectly balanced for flipping. This flips cleaner than knives twice the price. Definitely bookmarking this store for future orders.
Steven Allen –
Couldn’t ask for a better balisong honestly. Weight is perfectly balanced for flipping. Action is smooth right out of the box, no break in needed. Handles have a great grip even during fast flips. Already planning my next pickup from this store.