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Rusty blade cleaning?

I found today an Opinel 8 that I thought I had lost or was stolen.
Sadly the blade now has some light rusting. Grandad would have put engine oil into a jar, and pushed the blade in and out of that to clean it.
Is there something better?
 
 
I found today an Opinel 8 that I thought I had lost or was stolen.
Sadly the blade now has some light rusting. Grandad would have put engine oil into a jar, and pushed the blade in and out of that to clean it.
Is there something better?
I'm commenting to follow this thread, but also because I have a Kukri that belonged to my great grandad (I think) that needs restoring.

@vvaannmmaann do you have any photos?
 

ugly

LE
Moderator
OOOO steel wool and any light oil/lube
 

OneTenner

LE
Book Reviewer
Autosol

That's AUTOSOL, not anything else that may sound similar. ;)
Don't excessively 'spot clean' the rusty bits, you need to clean the whole blade equally otherwise the rusty bits will end up with a different optical quality.
If you have a roll of rifle cleaning cloth, that's ideal for polishing the blade with the Autosol.
 

DSJ

LE
I used bicarbonate of soda mixed into paste and rubbed onto the blade with tin foil (and a tooth brush). Had reasonable success, but as a carbon steel blade it has darkened in colour.
 
On a separate, but related note, I have a working kukuri that is lightly rusted, but with some notches in the edge through use/misuse.

I'm assuming it's a bit much to try and sharpen these out by hand. What would happen if I used a grinder and some oil?

Not after a shiny finish, since it's a working knife, just a sharp edge and de-rust.
 

Teeblerone

War Hero
Present of an old 'gentleman's penknife' and an Army clap knife. Brass wire wheel cleaned a lot of the rubbish off & left the 'character'.
 
I undertake a bit of rust removal using electrolysis as per the pics.

Assuming your rust is just surface, and no pitting you should be able to remove it with the application of 180 grade wet & dry and a little elbow grease. I find a squirt of WD40 will create an abrasive solution to help grind it off.

Perhaps to finish return the blade to shiny with some 240 grade wet & dry.

knife.jpg
knife_02.jpg
knife_03.jpg
 

Teeblerone

War Hero
On a separate, but related note, I have a working kukuri that is lightly rusted, but with some notches in the edge through use/misuse.

I'm assuming it's a bit much to try and sharpen these out by hand. What would happen if I used a grinder and some oil?

Not after a shiny finish, since it's a working knife, just a sharp edge and de-rust.

tempering/hardness problems unless a slow speed on the grinder?
Maybe a carborundum scythe stone, then oilstone?
I'm a bit sentimental and don't like the idea of using a machine on a decent blade
 
On a separate, but related note, I have a working kukuri that is lightly rusted, but with some notches in the edge through use/misuse.

I'm assuming it's a bit much to try and sharpen these out by hand. What would happen if I used a grinder and some oil?

Not after a shiny finish, since it's a working knife, just a sharp edge and de-rust.
" Grinders " as in the bench machines don't use oil stones.

An angle grinder with a fine 120 grit flap disk will take all the burrs out and leave it razor sharp but you have to be skilled in using grinders.
 

Teeblerone

War Hero
I undertake a bit of rust removal using electrolysis as per the pics.

Assuming your rust is just surface, and no pitting you should be able to remove it with the application of 180 grade wet & dry and a little elbow grease. I find a squirt of WD40 will create an abrasive solution to help grind it off.

Perhaps to finish return the blade to shiny with some 240 grade wet & dry.

View attachment 504560View attachment 504561View attachment 504562
Excellent result! Great looking, ahem, chopper
Bit of skill to get a thick blade that sharp
 
tempering/hardness problems unless a slow speed on the grinder?
Maybe a carborundum scythe stone, then oilstone?
I'm a bit sentimental and don't like the idea of using a machine on a decent blade
Anything hardened , drills, chisels, knives ect you are grinding on a bench grinder you should have a water pot next to the machine to keep dipping it in , if you are getting colours coming up on your piece , straw, blue, purple , you have knackered the temper.
 
On a separate, but related note, I have a working kukuri that is lightly rusted, but with some notches in the edge through use/misuse.

I'm assuming it's a bit much to try and sharpen these out by hand. What would happen if I used a grinder and some oil?

Not after a shiny finish, since it's a working knife, just a sharp edge and de-rust.

Go pick up a whetstone from a car boot sale. Have a look at the video below. It seems the difference between straight and curved blades is that for the latter you move the edge of the blade in the shape of the curve to maintain and even edge.

 
Love watching the renovation jobs on Youtube. Impressive.
 

OneTenner

LE
Book Reviewer
On a separate, but related note, I have a working kukuri that is lightly rusted, but with some notches in the edge through use/misuse.

I'm assuming it's a bit much to try and sharpen these out by hand. What would happen if I used a grinder and some oil?

Not after a shiny finish, since it's a working knife, just a sharp edge and de-rust.
I'd use an axe sharpening puck initially to cut past the notches, a grinder will take the metal away too quickly risking losing the profile of the blade, then work down in grit size - probably 800 or 1000 will be ok for a working knife, if you want to lose many hours, get a 2500 / 6000 mud stone ...

ETA - I've never sharpened a Kukuri so i'm not sure if it's a single or double grind edge, if it's a double grind, it might be worth thinking about taking the opportunity to re-grind it to a single as they're better for working knives - easier to sharpen and keep their sharpness longer.
(sort of) explained here The Only Article On Knife Grinds You'll Ever Need - I Made A Knife!
 
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I'd use an axe sharpening puck initially to cut past the notches, a grinder will take the metal away too quickly risking losing the profile of the blade, then work down in grit size - probably 800 or 1000 will be ok for a working knife, if you want to lose many hours, get a 2500 / 6000 mud stone ...
I have an angle grinder, don't want to spend any cash and don't want to spend hours on the job.

I was more after a "don't do that, or you'll knack it", but since no one has warned me...
 

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