Jump to content
I Forge Iron

What alloys are food-safe?

Recommended Posts

Hi everyone!

I am currently creating a multitool similar to the Gerber Shard from an old wrench, which I suspect to be a chrome-vanadium steel. The tool features a spoon, a short prybar, bottle opener, a sharpened edge and a flathead screwdriver. Steels with chromium seem to be food-safe from what I found out online, but how about the added vanadium? The oxides at least are apparently somewhat toxic.

Not knowing this, I have finished an earlier version of it a while ago from the same steel (simply the other side of the wrench), which did indeed give the food a somewhat metallic-biting aftertaste. Is this simply because I just tasted untreated metal or might this be a very light form of poisoning?

Are there any common steel additives that are known to be poisonous or at least not really food-safe?


Thanks in advance!

Link to comment
Share on other sites

Wrenches, if shiny, are chromium (and other trace metals) plated. The heated plating and sub-surface layers can indeed be poison! An old black oxide finished wrench would be a safer choice, with the surface sand blasted clean.

Non-magnetic grades of stainless steels are typically food safe, but make lousy tools.

Link to comment
Share on other sites

  • 2 weeks later...
7 hours ago, arftist said:

I saw a black oxide finish on s.s. that was awesome. Anyone know how?

What alloy?  If 300-400 series, maybe hot caustic soda and some salts, depending on alloy.  Danger, danger, Will Robinson!

Fume hoods, ventilation, PPE are in order...  

Link to comment
Share on other sites

I do a bit of cooking and most reactions with metals require heat, extended time in contact, or acidic foods. That is why copper pots and pans are plated with tin, unless you are working with eggs , then you use unplated.  Look at the Flint water issue, it was OK for decades until it was attacked by a new water source that was corrosive. 

Most screw machine stock has lead added for machinability, but there is a movement to get away from it due to health concerns. 

Nickle is an allergen for some, and is found in many stainless alloys, and steels. 

To be sure, buy new material. 

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...