Cleaning a carbon blade.

[Zammo]

My Frosts Mora has become filthy with use, it has black stains along the blade that seem to have my finger prints ingrained in them. I used it for cutting food such as cheese and this put a lot of the stains on it. I've tired to clean it with fairy liquid, WD-40 and by heating the blade but none of this has worked. Now I'm a bit worried about using it for food prep as it's so grubby.

Is there any way to clean it?

 

[davep90]

My Frosts Mora has become filthy with use, it has black stains along the blade that seem to have my finger prints ingrained in them. I used it for cutting food such as cheese and this put a lot of the stains on it. I've tired to clean it with fairy liquid, WD-40 and by heating the blade but none of this has worked. Now I'm a bit worried about using it for food prep as it's so grubby.

Is there any way to clean it?

carbon steels naturally gain stains and a kind of patina. you can use metal cleaner like autosol etc i suppose or something similarly abrasive. I personally think it gives the knife character and wares off eventually or evens out with more staining.
The fact that you heated it up however means that you probably need a new one for sure. I suppose at least it wasnt an expensive knife!
dave

 

[Zammo]

Why what will heating the blade up do? It hasn't made any difference to mine.

 

[Lodian]

What temp did u heat it to?

 

[davep90]

heating the blade will soften it making it useless

 

[w00dsmoke]

If you rub the blade with steel wool you should be able to get the blade back to it's nice n shiny state.

 

[Zammo]

I just held a lighter under it. I tried to clean it with wire wool but that didn't work either.

 

[EdS]

don't use WD40 it reacts with the metal. Use 3 in 1 or similar type of light lub oil (or decent olive oil). WD40 is not a normal oil - it is designed to get rid of water from already wet items (hence WD - water dispersent) not to clean and protect them.

 

[BorderReiver]

If you mean clean,as in safe for food,then soap and water will be fine.Dry and rub with a little vegetable oil to protect.

If you mean bright and shiny like a new pin,why bother?It won't make it work any better.

If you want to have a nice shiny knife,buy two,use one and keep the other one in a drawer.

 

[Biddlesby]

I'd lightly clean with autosol, soap and water then coat with an edible oil. But accept that carbon steel will not stay lovely and shiny without either no use or obsessive cleaning.

 

[Zammo]

I just want it to be safe to use for food prep.

 

[spamel]

Well, carbon steel will taint foods so perhaps a stainless mora would be in order! The patina is actually a good thing as it offers a little more rust proofing then a clean shiny carbon blade. If you have just passed the knife through a flame, then it should be fine. If you heated the blade up though, it is screwed! Just clean the knife as you would a knife at home, put some edible oil on to protect it and so that you don't poison yourself and keep it in its' sheath whilst out and about. Try to store the knife out of its sheath though, especially if it is a leather sheath.

 

[Mirius]

Carbon steel taint food? Well I guess that it might, but there are going to be an awful lot of chefs out there who are going to be surprised by that - unless H&S have banned them in the last couple of years.

 

[spamel]

Try chopping an apple with a carbon steel knife, it goes a funny colour where you cut it. You also get a slight metallic taste.

 

[Zammo]

Ok thanks for all your replies, I was just worried that the dirt on the blade might be harbouring nasties. But it seems like it's all good.

 

[spamel]

So long as you clean it now and then, you'll be fine. I think we worry these days too much about hygiene in relation to washing everything every five minutes, eating from scrupulously cleaned pots and the like. Take a look at the people in Africa, although they keep their kit clean, it isn't sterilised! The body will become immune to nasties if given a chance.

Of course, I don't mean that you should never wash anything ever again, you could end up with the trots, but a simple wash after use and then dry and put away will be fine. When cleaning your billy, throw a bit of ash from the fire in and then some water, give it a scrub, dump the water away from a water source, rinse and then put over the fire until it is just dry. The heat will kill any bad bacteria, and you could do your knife at the same time. If you are just waving it through the flame it won't harm your blade.

 

[dwardo]

So long as you clean it now and then, you'll be fine. I think we worry these days too much about hygiene in relation to washing everything every five minutes, eating from scrupulously cleaned pots and the like. Take a look at the people in Africa, although they keep their kit clean, it isn't sterilised! The body will become immune to nasties if given a chance.

Of course, I don't mean that you should never wash anything ever again, you could end up with the trots, but a simple wash after use and then dry and put away will be fine. When cleaning your billy, throw a bit of ash from the fire in and then some water, give it a scrub, dump the water away from a water source, rinse and then put over the fire until it is just dry. The heat will kill any bad bacteria, and you could do your knife at the same time. If you are just waving it through the flame it won't harm your blade.

"throw a bit of ash from the fire in and then some water" Great idea I use a bit of spaggy moss when up north or a bit of fine gravel if at the waters edge.

The idea of using ash is great as its allways about when im out....

 

[spamel]

Can't take the credit, Wayland posted about it a while back and it does work. As he said, soap used to be made from fat and ash, whic is what you'll have if you add water and ash to a greasy billie!

 

[Eric_Methven]

Can't take the credit, Wayland posted about it a while back and it does work. As he said, soap used to be made from fat and ash, whic is what you'll have if you add water and ash to a greasy billie!

Just to expand on that a bit, wood ash, when wet gives off potassium hydroxide (also known as lye) and was used in the proces of converting fat to soap. Originally soap was made from fat or oil. Using potassium hydroxide (an alkali), or commercially sodium hydroxide (also known as caustic soda) will convert fat (an acid) to a neutral pH state and make a material which will cause dirt molecules to separate from clothes, skin, pots etc and adhere to itself. This is then washed away with water taking the dirt with it. The material is soap. If it's made with vegetable oil, it becomes liquid soap. If it's made with fat (or hydrogenated oil) it becomes bar soap.

Adding ash to greasy pots allows the potassium hydroxide to convert the grease to a soapy state and can be washed away with water afterwards.

Eric

 

[markheolddu]

You can add your own patina to a carbon steel knife by vinegar etching it. helps to protect it from rust to. Just soak some toilet paper in ordinary vinegar wrap around the blade and leave over night and you have nearly instant patina.

Mark