What Is The Best Way To Get Rust Spots Off Of A Carbon Steel Blade?

Razor

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Dec 8, 1999
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I let my son borrow my spyderco PM2 in 5100 carbon steel. He let the blade get rust spots on it. I would like to clean the blade up. Would sticking the knife blade in a potato for a couple hours work? Are they better ways to clean it up of the spots? Should I just leave them there?
 
You could try some Flitz metal polish or the like. If that dosen't do it, try 0000 steel wool.
 
You could try some Flitz metal polish or the like. If that dosen't do it, try 0000 steel wool.
No, too much work.

Bar keepers Friend is the best kept secret.

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I got this "Super Rust and Tarnish Eraser" from knife center, which essentially is a rubber eraser with very mild abrasive in it. It works great as a first line of treatment for removing patina and rust. If that didn't work, then I would move onto 0000 steel wool.
 
I have some bar keepers friend!

Try oiling the blade right away after your done using the BFK,my Mom had some bread pans that were really old but still in good shape and from her using them for baking other thing's where she put oil or cooking spray in the the pan and the whatever it was she baked caused the oil to go brown and build up.

I used BFK and stainless steel wool to get the brown crap off and it came off really fast but the problem was I let them sit over night to dry and they rust,I just took BFK and scrubbed the rust off then I dried them and sprayed them with cooking spray and wiped off the extra and they were fine,I can't say for sure it was the BFK that caused them to rust if it was the oil seemed to neutralize it and they didn't rust again.

I guessing you have the BFK to clean your sharpening stones,you wouldn't believe how people I have had email me or ask me on Facebook what I use to clean my stones and people will say they have been using BFK for years and have never tried it on their sharpening stones,nothing compares or works as well on for cleaning sharpening stones.
 
I’ve been meaning to get hold of some BKF, but it’s not readily available in the UK. The following is an example of what is available this side of the pond. Does it look to be the same product despite the difference in branding?

https://www.sainsburys.co.uk/shop/P...VxfhRCh0AnQLcEAQYAiABEgIFf_D_BwE&gclsrc=aw.ds

Mods - hope it’s OK to paste this link as they do not sell anything in competition to the contributors on this forum.

thanks
 
If you can't get Bar Keeper's Friend, look for something that contains oxalic acid. That is the magic bullet ingredient.
 
I’ve been meaning to get hold of some BKF, but it’s not readily available in the UK. The following is an example of what is available this side of the pond. Does it look to be the same product despite the difference in branding?

https://www.sainsburys.co.uk/shop/P...VxfhRCh0AnQLcEAQYAiABEgIFf_D_BwE&gclsrc=aw.ds

Mods - hope it’s OK to paste this link as they do not sell anything in competition to the contributors on this forum.

thanks

C Craig James Contact me at wadenorton2008@yahoo.ca I maybe able to help you get some BFK title the email Bar Keepers Friend,also do not buy the liquid stuff only the powder in the gold canister,I have tried the liquid stuff that has a gold label and it has only worked for me if it has sat for at a year for it to separate and go hard in the bottom of the bottle letting a yellow liquid come to the top of the bottle,the yellow liquid works.

They also make a stainless steel version and I have not tried it and it is in a silver canister so if you buy that one be aware it may not work.
 
I’ve been meaning to get hold of some BKF, but it’s not readily available in the UK. The following is an example of what is available this side of the pond. Does it look to be the same product despite the difference in branding?

https://www.sainsburys.co.uk/shop/P...VxfhRCh0AnQLcEAQYAiABEgIFf_D_BwE&gclsrc=aw.ds

Mods - hope it’s OK to paste this link as they do not sell anything in competition to the contributors on this forum.

thanks

The ingredients listing on that linked page does show oxalic acid in the mix; that's the magic stuff that makes BKF work. BKF in the US also comes in a liquid version, although it seems more dilute in how it works (less aggressive, slower-working). With just light spotting on a blade, it might still be enough. And on a carbon (non-stainless) blade, a little less aggression might be a good thing anyway. Oxalic acid is strong enough to etch even stainless steel, if left in contact long enough (> 60 seconds or so, for the powdered BKF product).
 
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Thanks gents, and wade I’ll try the stuff I can get locally. Thanks for the offer though. Much appreciate. May well send you an email about that Ukrainian diamond paste tho. Wanting to try it instead of the green rogue I’m currently using!
 
BKF is the 8 lb sledgehammer in rust removal. I have used it a lot on seriously rusted blades where other methods aren't working. To neutralize the acid I scrub with a baking soda paste afterwards.

BKF is really harsh on carbon steel. It will react so strong their will be a stench. Use it if need be as soon as the rust is gone get the BKF off and neutralize it.

Some disagree but I have had blades yellow the next day if not adequately treated post BKF. Other derusting techniques, no yellowing.
 
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