Rust problems

J

Jason Fry

Knifemaker / Craftsman / Service Provider
Joined
Jun 5, 2008
Messages
3,159
I'm struggling with rust, and looking for advise. I developed my techniques mostly on stainless, and this forged stuff is giving me fits keeping it clean. I typically hand finish to 400 or 600, with rhynowet paper and WD40 as lube. It's darn clean when I'm done. I usually do this finish work before guard fitting, then touch up any scratches afterward, then glue everything up. I usually coat the blade with a light coat of mineral oil, then blue painter's tape. I'm getting some discoloration and occasionally real rust underneath the tape. I can re-sand and get it off, but I feel like the seed has been planted and it'll always be a problem on the blade from then on. I'll be a little honest, that's one of the reasons I have tended toward more stainless and less forging over the past 8 years, because it pains me to think that a knife will only go down hill from my table. On a stainless knife, I have more confidence it will still look good 10 years from now. On a carbon knife, I can barely keep it clean for a few months.

Looking for advise here. Is there a step I'm missing? Is it something about the oil, or the tape, or the sequence? Is there a product I can use instead, to keep the rust at bay?
 
I struggle with rust in my shop and have tried more than 10 different oils/products. This is a good reference http://www.dayattherange.com/?page_id=3667

What I've found is that underlying moisture is the root problem; no oil will prevent rust if there is underlying moisture - regardless of oil quality or quantity.

I've implemented a strict rust-prevention protocol: any time the steel encounters water or a water-containing product, I wipe, then dry in a toaster oven, then I apply oil while still warm. My previous process was wipe, then fan dry.

Before implementing this protocol, I was getting some rust - even with top-of-the-line products such as CorrosionX.

Since using this protocol, I haven't noticed a difference between expensive products such as CorrosionX and cheaper products such as 3-in-1 oil.
 
I think that may be part of the issue... it's been raining here off and on for three or four weeks. The rusted knives that prompted this post were hand finished on rainy days.
 
If you use abrasive paper, files ,etc on carbon steel , then use the same on SS you are asking for trouble as carbon S particles will contaminate the SS and cause rust.
You could coat the SS with a good rust preventative like RIG then wrap in rust preventative paper .
You could use a dehumifier even in a small room to store blades.
You could move to AZ !
 
I understand your frustration Jason. I'm anal beyond belief, about my knives being in pristine condition when they leave my shop. I only do hand finishes, and like you, I generally go to a 600 grit finish using Rhynowet Redline with WD-40 as a lubricant. I'm one of those that can just touch carbon steels and they will quickly begin to show signs of rust. Very frustrating indeed. The best way I've found to somewhat combat the issue, is to take the surface to a higher grit finish. Problem is, that 600 grit finish is the sweet spot for a satin finish to my eye and continues to be my preference. If you don't want to take the finish higher in grit, you just have to be anal about keeping the steel clean and oiled. I've gone so far as to keep the steel completely submerged in mineral oil during the course of working on the build up to the point that it's ready for the handle. After nearly 3 years of working with carbon steels exclusively, I've recently switched to stainless (CTS-XHP) for these exact reasons. Things are going well so far and my time in the shop is far less frustrating.

I doubt any of my reply really helps you much, but I definitely feel your frustration man. Good luck in your fight against the rust!
 
I've found vegetable oil to be the best solution to this problem. Heat the blade a bit, wipe on a thin coat, wipe off the excess. Just like a cast iron frying pan. The oil oxidizes and creates a layer that's less permeable than any liquid RP in my experience.

The knives I keep in my shop, the ones sprayed with WD40 or similar always end up spotting with rust. The ones with veg oil never seem to.

My biggest rust problem is getting a leather sheath completely dry before sticking a knife in it.
 
Yep, it is a constant struggle, I have found that drying the knives very good, A quick spell in the oven is what I use, and then I coat will 3 in 1 oil and I wrap knives in paper towel, and make sure there is enough oil on the knife to soak into the towel. Then I store them in a rubbermaid tote in my house. I live in the south, so anything outside is prone to rusting. DAMN the humidity!
 
Adam Buttry said:
After nearly 3 years of working with carbon steels exclusively, I've recently switched to stainless (CTS-XHP) for these exact reasons.
Click to expand...

I'm with you there, except that I'm working toward JS certification. After 5 years of mostly stainless, I'm back to carbon for a bit.
 
kuraki said:
My biggest rust problem is getting a leather sheath completely dry before sticking a knife in it.
Click to expand...

Food dehydrator overnight will solve that. I bought mine at a garage sale for $5. You don't want too much heat, but the dehydrator sure speeds up the process.
 
The blue painters tape will discolor or rust blades is left on overnight.

As far as "keeping carbon blades clean" carbon is all we use in the kitchen here and just let them patina over the years. Rinse and dry, no oil. Never had one rust. Very humid summer here and no rusty blades in the house or the shop.
 
I have seen the same issues as Don with the blue painters tape. I switched to a quick wipe on mineral oil then a paper towel and wrap with electrical tape. This keep and sort of tape adhesive off off the blade.
 
I have had bad luck as well leaving blue painters tape on a blade. Now I wipe the blade down with Rem Oil or something similar then wrap with a sheet of phone book paper and cheap Harbor Freight electrical tape.
 
Don Hanson III said:
The blue painters tape will discolor or rust blades is left on overnight.

As far as "keeping carbon blades clean" carbon is all we use in the kitchen here and just let them patina over the years. Rinse and dry, no oil. Never had one rust. Very humid summer here and no rusty blades in the house or the shop.
Click to expand...




I think the really good no bleed tape for latex paint has some sort of water absorption feature like there is in diapers that seals the edge for no paint bleed, but holds moisture.
Or as mentioned above, it's acidic or something.



I think Texas must have lower humidity than we have here and I have much less rusting on clean bare steel.

Try other cheap tape, the plain brown stuff.

Also try taping inside out.

Wrap the tape inside out so it sticks to itself, but the blade gets the plain paper side.
Then give a half twist and tape over again so you seal the sticky layer in.

Even better with a slight smear of Vaseline underneath that tape.
 
Frog Lube and WD 40 Corrosion inhibitor are the best at keeping corrosion away.

Normal WD40 performs as well as most the traditional well known protection products.

I will take a carbon blade and clean it off with windex or soap and water and then hit it with WD40 wrap in paper towel and spray the paper towel.

For long periods of time I will use the corrosion inhibitor.

Here is some testing showing what works best

http://www.dayattherange.com/?page_id=3667
 
Last edited:
I have to ask. How can you send out knives you can expect the receiver to have rust problems with?
Frank
 
Frank Niro said:
I have to ask. How can you send out knives you can expect the receiver to have rust problems with?
Frank
Click to expand...

If I have rust, I remove it with sandpaper to get it as clean as I can. They will be clean and treated when I send them out. It's the best I can do.
 
Darrin Sanders said:
Renaissance wax.
Click to expand...

I bought a tin of that based on comments here but have gone back to veg oil because the wax didn't protect as well for me.

Adam mentioned Frog Lube, which is a veg oil, like FireClean. Both just expensive vegetable oils.

The other benefit is it's food safe.
 
You must log in or register to reply here.
Back
Top